WO2002049999A1 - Process for preparation of polyhydric alcohols - Google Patents

Abstract

The invention relates to a process for preparation of polyhydric alcohols which comprises efficiently oxidizing an olefin having a carbonyl group with molecular oxygen and subjecting the obtained reaction product to hydrolysis and reduction, more specifically, a process for preparation of polyhydric alcohols which comprises reacting an olefin having an optionally protected carbonyl group and an ethylenic double bond in the molecule with oxygen and an alcohol to thereby obtain a reaction product containing an acetal and/or a ketal and hydrolyzing and reducing the acetal and/or the ketal.

Description

 Description Method for producing polyhydric alcohols

 In the present invention, a compound containing an acetal and Z or ketone is obtained by reacting an olefin having a double bond with a carbonyl group or Z or a protecting group thereof in the same molecule with oxygen and an alcohol, The present invention relates to a method for producing polyhydric alcohols through hydrolysis and reduction reaction. -Background technology

 The site of the ethylenic double bond of the olefins having a carbonyl group and / or a protecting group in the same molecule is led to a hydroxyl group, an epoxy group, a carbonyl group, etc., and reduction thereof gives polyhydric alcohols. These synthetic methods are being studied with a focus on the synthetic method of 1,3-propanediol, which is useful as a raw material for polyester. Specifically, a method for producing 3-hydroxypropanal by hydrating acrolein and then reducing it is described in USP 5093537, JP-A-10-212253 (USP 6140543), and JP-A-8- No. 143502.

 Further, as another method for synthesizing 1,3-propanediol, Japanese Patent Application Laid-Open No. 9-20703 discloses a method for reducing dalicidaldehyde obtained by oxidizing acrolein with aqueous hydrogen peroxide.

However, the methods disclosed in the above-mentioned USP 5093537, JP-A-10-212253 (USP 6140543), JP-A-8-143502 and the like cannot increase the reaction conversion during the 7K summation reaction. In addition, when the conversion of the reaction is increased, the selectivity is reduced, and when the substrate concentration during the reaction exceeds 17%, there is a disadvantage that by-products increase. In addition, this reaction uses water as a solvent, but the resulting 3-hydroxypropanal or, after its reduction, 1,3-propanediol is well dissolved in water, so the water and product are extracted. Another drawback is that separation becomes difficult and large amounts of water must be separated by distillation. In addition, the method disclosed in JP-A-9-20702 uses expensive hydrogen peroxide as an oxidizing agent, and glycidaldehyde cannot be obtained in high yield unless this hydrogen peroxide is used in excess. On the contrary, when hydrogen peroxide is used in excess, there is also a problem that aldehyde is oxidized to carboxylic acid as a side reaction.

 As described above, polyhydric alcohols such as 1,3-propanediol are useful as a raw material for polyester, and it has been desired to develop an industrially advantageous method for producing the same.

 On the other hand, the oxidation reaction of orefin with molecular oxygen is an industrially useful method, and a particularly useful method is a reaction generally known as Wacker reaction. That is, a method for producing acetoaldehyde from ethylene and acetone from propylene using molecular oxygen using an aqueous solution containing palladium salt and copper chloride as a catalyst has been industrially adopted.

 Examples of applying this reaction to the above compounds such as acrolein are described in J. Org, Chem 1987, 52, 1758-64 and Bull. Chem. So JPIL, 63, 166-169 (1990). Here, the results are reported that the reactivity is very poor and the TOF is 1 or less. In other words, it is considered that applying the Wacker reaction as described above to olefins having an electron-withdrawing group such as a carbonyl group is very poor in reactivity. Was considered a difficult route. Disclosure of the invention

 The present inventor has made intensive studies to solve such a problem, and as a result, even if the olefins have a carbonyl group as an electron withdrawing group, the oxidation reaction proceeds with high reactivity and selectivity. By constructing a reaction system that can obtain and further efficiently hydrolyze and reduce the acetal and the octane or ketal compound obtained thereby, even polyolefins having a carbonyl group can be converted at a high conversion rate, and They found that they could be produced with high selectivity, and completed a new synthetic route that could be applied industrially.

That is, the gist of the present invention is to react oxygen and alcohol with an olefin having an ethylenic double bond having a strong ruponyl group and / or a protective group thereof in the same molecule. To obtain a reaction product containing an acetal and / or a ketal compound, and then hydrolyze and reduce the acetal and the Z or ketone compound to produce polyhydric alcohols. Olefins having a carbonyl group and an ethylenic double bond in the molecule are reacted with a protecting agent to protect the carbonyl group, and then the olefins having the protected carbonyl group and ethylenic double bond are protected. Is reacted with oxygen and alcohols to obtain the corresponding acetal and / or ketal compound, and then the acetal and / or ketal compound is deprotected, hydrolyzed, and reduced to produce polyhydric alcohols. Exists. BEST MODE FOR CARRYING OUT THE INVENTION

 The present invention uses an olefin having an ethylenic double bond having a carboxy group in the same molecule as a reaction raw material, or an olefin which is obtained by protecting the carbonyl group of the olefin with a protecting group. Is used as a raw material. And, from these raw materials, a corresponding polyhydric alcohol is produced through an oxidation reaction, hydrolysis, and reduction reaction.

 In the present invention, there are roughly two reaction routes.

 The first reaction route is to oxidize olefins having a strong luponyl group and Z or a protecting group thereof and an ethylenic double bond in the same molecule to obtain an acetal and a Z or ketal compound. This is a method for producing polyhydric alcohol by decomposition and reduction. The second reaction route is to react an olefin having a carbonyl group and an ethylenic double bond in the same molecule with a protecting agent to protect the carbonyl group, and then oxidize the carbonyl group to form phenol and Z. Alternatively, a ketal compound is obtained and then deprotected, hydrolyzed, and reduced to produce a polyhydric alcohol. In the first and second reaction routes, the oxidation reaction, hydrolysis, and reduction reaction are common steps.

 An example of the reaction formula in the second reaction route of the present invention will be described. In the formula, R ′ and R ″ represent a hydrocarbon group.

 First, the reaction formula of the first protection reaction is shown in (1-1a).

上記反応で得たカルボニル基が保護された化合物を酸化するが、 その反応式のT + Η, Ο formula (1-1a) o

The carbonyl group obtained in the above reaction is oxidized with the protected compound.

—An example is shown in Equation 11-b. ,, OR ', OR'

+ 2R "OH + 1/20 ₂ + H ₂ 0

OR 'OR "OR'

 Formula (1-b) An example of a reaction formula for converting a product after oxidation to a carbonyl group by deprotection is shown in Formula 2-a. ·

"RO ^^^ NO OR '" RO,

II + H ₂ 0 * ~ I) + 2ROH

OR "OR 'OR" O

 Formula (2-a) Formula 2 _b shows an example of a reaction formula in which acetal and Z or ketal after deprotection are hydrolyzed into a carbonyl group by force D hydrolysis.

^^^ + ¾ *-+ 2R "OH

 OR "O O O

 Formula (2-b) An example of a reaction formula for obtaining a polyhydric alcohol by reducing the obtained carbonyl group to a hydroxyl group is shown in Formula 2-c.

+ 2H ₂ ——-HO ^^^ OH formula (2-C) oo

The above reaction route is the case of the second reaction route. In the case of the first reaction route, the protection reaction of the formula 11a is omitted, and the olefins having a carboxy group are used as starting materials, and The oxidation reaction of b is performed. In this case, of course, the deprotection reaction of Formula 2-a becomes unnecessary.

In some cases, the order of the deprotection reaction (Formula 2-a) and the hydrolysis reaction (Formula 2-b) may be reversed. In addition, carbonyl protecting groups such as acetal, ketal When deprotection by hydrolysis and conversion to a carbonyl group as in the above, deprotection and hydrolysis can be performed simultaneously. When the protecting group of the carbonyl group is deprotected by a reduction reaction, the deprotection and reduction are performed simultaneously, and when the protecting group can be directly converted to a hydroxyl group by the reduction reaction, the deprotection is not required. The desired polyhydric alcohol can also be obtained.

Starting material>

 The starting material of the present invention is an olefin having an ethylenic double bond having a carbonyl group in the same molecule.

 The olefins of the present invention may be either linear or cyclic. The chain number of carbons of the olefins is usually 2 or more, preferably 3 or more, and usually 25 or less, preferably 10 or less. In the case of cyclic olefins, it is usually 4 or more, preferably 5 or more, and usually 10 or less, preferably 8 or less. The number of double bonds in one molecule of the olefins is not particularly limited, but is usually 8 or less, and preferably 3 or less. The position of the double bond may be anywhere. Examples of the carbonyl group include an aldehyde group, a ketone group, and a carboxyl group, and an aldehyde group is preferable. The number of carbonyl groups in one molecule of the olefins is not particularly limited, but is usually 8 or less, preferably 3 or less.

 The positional relationship between the double bond and the hydroxyl group is not particularly limited as long as it is present in the same molecule. Preferably, the number of carbon atoms present between these two groups is 3 or less, more preferably 0. It is better to be close to each other. Most preferred are β-unsaturated carbonyl compounds.

 These chain or cyclic olefins may have a substituent at any position of the main chain and may have a condensed ring. Examples of the substituent include an alkyl group having 1 to 23 carbon atoms, an alkoxy group having 1 to 23 carbon atoms, and a halogen group such as an aryl group having 6 to 22 carbon atoms such as a phenyl group, a chloro group, and a promo group. Group, nitro group, etc., and the number of substituents may be one or more.

The above-mentioned olefins may be directly subjected to an oxidation reaction, but may be subjected to an oxidation reaction after protecting a carbonyl group to form a protecting group for a carbonyl group. A protecting group for a carbonyl group is a protecting group for preventing a carbonyl group from reacting in an oxidation reaction step. Any group may be used as long as it is a carbonyl group that has been converted and can be converted into a hydroxyl group by deprotection, hydrolysis and / or reduction. .

 Examples of the carbonyl-protecting group include an acetal group, a thioacetal group, a ketal group, a thioketal group, an ester group, and the like. Among them, an acetal group and an ester group are preferable, and an acetal group is particularly preferable.

 Even if these carbonyl groups react with the alcohol or oxygen used in the reaction during the oxidation reaction, there is no problem as long as they can be converted into hydroxyl groups in the subsequent steps.

 When olefins having a plurality of carbonyl groups are used, not all carbonyl groups need be protected.

 Examples of the above-mentioned olefins having a carbonyl group and the olefins having a protected carbonyl group include acrolein, methacrolein, crotylaldehyde, 2-hexenal, cinnamaldehyde, and 2-cyclohexane. Hexene force α, β unsaturated aldehydes such as lipoaldehyde, acrolein dimethyl acetal, lacquer reinethyl acetal, 2-pinyl-1,3-dioxolan, 2-vinyl-1,3-dioxane, etc. Benzene, vinyl methyl ketone, vinyl ethyl ketone, 3-pentene 1-2-one, etc., 3 unsaturated ketones, vinyl methyl ketone dimethyl ketal, 2, 2-ethyl vinyl 1,3-dioxolan, etc. Ketals, acrylic acid, methacrylic acid, cinnamic acid, 2-cyclohexenecarboxylic acid, etc. Α, β-unsaturated carboxylic acids, α such as maleic anhydride, etc .; 8-acid anhydride, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-hydroxyethyl acrylate, 3-hydroxy Examples include propyl acrylate, 4-hydroxybutyl acrylate, lactones such as acrotonolactone, and esters such as vinyl esters such as pinyl acetate and vinyl butylate. Of these, α, β unsaturated aldehydes are most preferably used.

<Protection reaction step>

 The protection reaction step is a step of reacting an olefin having an ethylenic double bond having a carboxyl group in the same molecule as a reaction raw material with a protective agent to synthesize a protective group for a carbonyl group.

As a reaction method in this step, a known method for protecting a carbonyl group is used. And is not particularly limited. In addition, the protecting group in the present invention may be any one which becomes a hydroxyl group by deprotection, hydrolysis and / or reduction reaction without returning to a carbonyl group by a deprotection reaction.

 The protecting group formed in this step is deprotected in the deprotection step, but if the protecting group that can use the same reaction conditions as the hydrolysis reaction is selected, the deprotection reaction and hydrolysis The reaction and the reaction can be performed simultaneously, and the number of reactors is reduced, which is advantageous in the process. A specific example of a reaction in which the deprotection reaction can be performed under the same reaction conditions as the hydrolysis reaction is a case where the carbonyl group of the starting material is a formyl group, that is, the compound is an aldehyde, and the protected form is acetate. No. The reaction of converting an aldehyde to an acetal is generally used as an acetalization reaction and as a reaction for protecting a carbonyl group. In addition, depending on the type of the carbonyl group, the carbonyl group may be lost by decarboxylation under conditions such as heating. In such a case, the carbonyl group is protected by acetalization or esterification. Specific examples include the case where the carbonyl group of the starting material is a carboxyl group, that is, the compound is a carboxylic acid, and the protected form is an ester. The reaction that converts the carboxylic acid to an ester is known as an esterification reaction.

 In the present invention, the functional group formed by oxidation is reduced through hydrolysis, even though it can be led to a hydroxyl group through oxidation, hydrolysis, and reduction without protecting the hydroxyl group. In this case, when more hydrogen is consumed than in the case of protection or when the conditions of the reduction reaction require high temperature and high pressure, it is preferable to convert the carbonyl group into the protective group. This is because the protecting group for the carbonyl group can be easily returned to the original carbonyl group in the deprotection step. Even if the same carbonyl group can be easily converted to each other by the esterification of carboxyl group and the hydrolysis of ester such as carboxyl group and ester group, it is better to convert it to a protecting group. preferable. In addition, if conversion to a protecting group can facilitate the separation of the target product and other compounds by distillation, or if the problem of the material of the equipment used in the present invention can be solved, conversion to a protecting group is required. Is preferred.

Examples of such olefins include aldehydes and carboxylic acids, specifically, acrolein, methacrolein, crotylaldehyde, 21-hexenal, cinnamaldehyde, 2-cyclohexenepotassium lipoaldehyde, and the like. Saturation Α, β such as aldehyde, vinyl methyl ketone, vinyl ethyl ketone, 3_penten-2-one, j8 unsaturated ketones, acrylic acid, methacrylic acid, cinnamic acid, 2-cyclohexene carboxylic acid And unsaturated ruponic acid. The protecting agent is appropriately selected according to the target product, and a known protecting agent which forms a protected phenol group can be used. Preferably, an alcohol is used, and most preferably, the same polyhydric alcohol as the target product is used. It is. The type of alcohol is not particularly limited, but it is preferable to use alcohol in which the equilibrium between the alcohol and the product is biased toward the product, since the conversion rate increases.

 For example, when the protection reaction is an acetalization reaction, an alcohol having 1 to 10 carbon atoms is usually used, among which polyhydric alcohols are preferable, and diols having 2 to 5 carbon atoms are particularly preferable. Specifically, ethylene glycol, 1,3-propanediol, 1,2-propanediol, 1,4-butanediol, 1,2-butanediol, 1,3-butanediol, 1,3-pentanediol And 2-, 2-dimethyl-1,3-propanediol.

 In addition, when the protection reaction is an esterification reaction, an alcohol having 1 to 10 carbon atoms is usually used. Specifically, methanol, ethanol, propanol, 2-propanol, ethylene glycol, 1,3-propane Diols and the like are exemplified.

 Since the alcohol used here is generated during the deprotection reaction, it is necessary to separate the alcohol from the target substance. Therefore, it is desirable to select alcohols that can be easily separated from the target. That is, for example, when distillation separation is employed as the separation method, those having a large boiling point difference between the target substance and the alcohol are preferable. The use of the same alcohol as the polyhydric alcohol of interest eliminates the need for this separation, making the process more advantageous. For example, when acrolein or acrylic acid is used as the olefin material, it is most preferable to use 1,3-propanediol, which is the target product, as the alcohol because there is no need to separate the alcohol from the product after the deprotection reaction. .

Acetalization and esterification are equilibrium reactions, and usually use either a carbonyl compound or a protective agent in excess. If an alcohol, which is a protective agent, is used in excess, the alcohol remains after the protection reaction. Normally, This alcohol must be removed before it is subjected to the subsequent oxidation reaction, but if the alcohol used in the oxidation step following the protection step is also used in this step, it is not necessary to remove the alcohol, and the process will not proceed. It is simple and economical because there is no cost to remove.

 As the protecting group of the carbonyl group for the oxidation reaction, all generally known protecting groups can be used, and the protected form is not particularly limited. Usually, the protected carbonyl group is one which can be converted into the original carbonyl group, acetal group, thioacetal group, ketal group, thioketal group, ester group, etc., preferably acetal or ketal and ester, specifically Typical examples are acrolein dimethyl acetal, acrolein getyl acetal, 2-vinyl-1,3-dioxolan, 2-vinyl-1,3-dioxane, and other vinyl esters, vinyl methyl ketone dimethyl ketal. Ketals such as 1,2,2-ethylvinyl 1,3-dioxolane, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-hydroxyethyl acrylate, 3-hydroxypropyl pyracrylyl Acid esters and 4-hydroxybutylacrylic acid esters Ters and the like are used.

 As examples of protecting the carbonyl group, a dehydration condensation reaction, specifically, an acetalization reaction of an aldehyde having a formyl group and an esterification reaction of a carboxylic acid having a carboxyl group will be described below. The acetalization and esterification by the dehydration condensation reaction can be carried out under the same reaction conditions except for the type of carbonyl group and the type of alcohol which is a preferable protecting agent. In the dehydration condensation reaction, an olefin having a carbonyl group is reacted with an alcohol using a catalyst in the presence of a catalyst to obtain an olefin having a carbonyl protecting group.

 The amount of olefins present in the reaction system is usually l vol% or more, preferably 5 vol% or more, and can be selected usually in the range of 99 vol% or less, preferably 5 Ovol% or less.

 Among these olefin raw materials, those which are liable to be polymerized by heat or the like or to undergo radical autoxidation are included. In such a case, it is advisable to add a radical scavenger such as hydroquinone or phenothiazine ^! Or a polymerization inhibitor to the system.

The amount of alcohols present in the reaction system is usually l vol% It is preferably at least 5 vol%, and usually at most 99 vol%, preferably at most 80 vol%.

 The molar ratio in the reaction system in the initial stage of the reaction between the carbonyl group of the raw material and the alcohol is not particularly limited, but may be in the range of 1/1 to 1/100. Within the above range, 1/1 to 1/95 is preferable, and the range of 1 / 1.2 to 1/90 is particularly preferable.

 The protection reaction of the olefins is usually carried out in the presence of an acid catalyst. Mineral acids such as hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid, Lewis acids such as lanthanoid triflate, polyacids such as heteropoly acid, solid acids such as ion exchange resin, zeolite and clay are used as the acid catalyst in this case. can do. Solid acids are convenient because of the ease of product separation. The addition amount of the acid is effective even in a very small amount and is not particularly limited, but is preferably at least 0.001 weight ratio, more preferably at least 0.01 weight ratio, and preferably at least 100 weight ratio with respect to the substrate. It is not more than 70% by weight, especially not more than 60% by weight. The reaction temperature depends on the type of reaction. If the reaction is carried out while distilling off water or an azeotrope, a temperature that can be distilled off is required.If the product is not removed out of the system, the lower the temperature is, the higher the attained equilibrium value is. is there. The reaction temperature is usually at least 100 ° C, preferably at least 150 ° C, more preferably at least 120 ° C. Further, it is usually at most 200 °, preferably at most 180 °, more preferably at most 150 °.

The protection reaction can be performed in a general manner. When each component of the catalyst is present in a solution state, the reaction can be carried out by contacting the substrate with alcohols for a specific reaction time in a batch reactor, or the substrate and alcohol can be produced in a continuous phase reactor. The reaction can be advanced by continuously supplying the compounds. On the other hand, when the catalyst of the present invention is insoluble in substrates or alcohols, that is, when a solid acid is used, and / or when the catalyst component is immobilized, the above-described liquid phase reaction may be used. Alternatively, a so-called trickle bed method in which a fixed bed is filled with a catalyst, and the corresponding substrate and alcohols are supplied in a liquid phase state and used, can be adopted. Both acetalization and esterification are equilibrium reactions. Therefore, after the reaction, a method of separating the starting material from the target product or removing the water, acetal, or ester generated during the reaction out of the system to push out the reaction is adopted. The method of removal outside the system is the addition of alcohol and a solvent that forms two layers. The method may be carried out while extracting the acetal or ester, distilling off the generated water by heating, or adding a solvent which forms an azeotropic composition with water and distilling off as an azeotrope. If none of the products is removed out of the system, a method such as raising the raw material ratio or lowering the reaction temperature to increase the attained equilibrium value is used to increase the conversion. <Oxidation process>

 Next, the oxidation step will be described.

 In the oxidation step, the olefins having an ethylenic double bond having a carbonyl group and a Z or a protecting group in the same molecule are reacted with oxygen and alcohols to mainly oxidize the olefin moiety to acetal and Z or ketal. This is the process of synthesizing the compound.

 That is, in the case of chain-like olefins, terminal olefins mainly produce ketals of base or methyl ketones, and internal olefins mainly produce corresponding ketals.

 In the present invention, the production of the olefins having an ethylenic double bond having a protective group does not necessarily have to be performed in the same place as the oxidation step, but includes a protective group previously produced in another place. Olefins having an ethylenic double bond may be used as a raw material.

 The oxidation reaction usually oxidizes olefins in a solvent in the presence of an alcohol using a catalyst, and the amount of olefins in the reaction system is usually l vol% or more, preferably 5 vol% or more. In addition, it can be selected in a range of usually not more than 99 vol%, preferably not more than 5 Ovol%.

 Among these olefin raw materials, those which are liable to be polymerized by heat or the like or to undergo radical automatic oxidation are included. In such a case, a radical scavenger such as hydroquinone or phenothiazine, a polymerization inhibitor and the like may be added to the system.

 As alcohols to be present in the oxidation reaction, acetal and Ζ or ketal mainly produced by the reaction are in equilibrium with aldehyde and Ζ or ketone, and this equilibrium is formed in the product, acetate or ketal. It is preferable to use a biased alcohol because it is less susceptible to further oxidation.

Further, alcohols that form a two-layer with a solvent such as an aliphatic or aromatic hydrocarbon are desirable. The reason is that by adding such alcohols during the reaction, After the reaction, the alcohols can be separated from the solvent by layer separation, and after the reaction, the product can be extracted from the catalysts dissolved in the alcohol layer, such as palladium, iron, and copper, by extracting with these hydrocarbon solvents. This is because separation becomes easy. When the product and the catalyst are separated by this two-layer separation, an additive can be added to efficiently perform the phase separation and to improve the product extraction rate. In addition, before phase separation, by-products, water, and the like, which hinder phase separation and extraction, can be separated. The two layers are mixed again after removing by-products, water, etc., which hinder extraction, from each layer once separated, or after removing the solvent and alcohol to increase the concentration of each component. Then, a method of increasing the extraction rate can be adopted.

 From the above viewpoints, alcohols used in the reaction are usually alcohols having 1 or more carbon atoms and 10 or less carbon atoms, among which methanol and polyhydric alcohols are preferable, and particularly preferable are carbon atoms. 2 to 5 diols. Specifically, methanol, ethylene glycol, 1,3-propanediol, 1,2-propanediol, 1,4-butanediol, 1,2-butanediol, 1,3-butanediol, 1,3-pentane Examples thereof include diol and 2,2-dimethyl-1,3-propanediol.

 In this step, ethanol and Z or ketal are obtained, and in the hydrolysis step, the alcohols used in this step are produced. When separating alcohols from the target substance, it is desirable to select alcohols that can be easily separated from the viewpoint of economy. That is, for example, when distillation separation is used as a separation method, those having a large boiling point difference between the target substrate and the alcohol are preferable. Also, it is preferable that the alcohol be the same as the target polyhydric alcohol. For example, when acrolein or its acetal is used as the olefin material, the target product is 1,3-butanol as the alcohol. The use of a diol is most preferred because it is not necessary to separate the alcohol from the product after the hydrolysis reaction.

The amount of alcohols present in the reaction system is usually at least l vol%, preferably at least 5 vol%, and usually at most 99 vol%, preferably at most 80 vol%, based on the entire reaction volume. Is within the range. The molar ratio of the starting olefins and alcohols in the reaction system at the initial stage of the reaction is not particularly limited, but may be in the range of 1/1 to 1/100. Within the above range, 1/1 to 1/95 is preferable, and 1 / 1.2 to 1/90 is particularly preferable.

 The catalyst used in this step is not particularly limited, and may be a homogeneous system or a heterogeneous system. Among them, a catalyst containing at least one of copper and iron or both copper and iron in addition to palladium is used. It is particularly preferable to use a catalyst in which all of palladium, copper and iron are combined. Many commercially available palladium, copper, and iron raw material compounds are known, and any of them can be selected.

For example, palladium compounds include palladium halides such as palladium chloride and palladium bromide, paradates such as Ν {Ν _φ Li ₂ PdCl ₄ , palladium nitrate, palladium sulfate, palladium acetate, palladium trifluoroacetate, palladium acetyl Palladium salts of inorganic or organic acids such as acetate, inorganic palladium such as palladium oxide and τΚpalladium oxide, and compounds coordinated with bases derived from these metal salts, for example, PdCl ₂ (CH ₃ CN) ₂ , PdCl ₂ (PhCN) ₂ , PdCl ₂ (PPh ₃ ) ₂ , Pd (en) ₂ Cl ₂ , Pd (Phen) Cl _2, etc., but are not limited thereto (here, en : Ethylenediamine, hen: 1,10_phenanthine. Among these palladium conjugates, from the viewpoint of the above-mentioned layer separation of the solvent and the alcohol, compounds in which paradates such as Na ₂ PdCl ₄ and Li ₂ PdCl ₄ and a base are coordinated, for example, PdCl ₂ (C¾CN) ₂ , PdCl ₂ (PhCN) ₂ , PdCl ₂ (PP) ₂ , Pd (en) ₂ Cl ₂ , Pd (Phen) Cl _{2 and the} like are preferable, and those which are well soluble in alcohols and hardly soluble in hydrocarbons are preferable. .

 Examples of iron compounds include chlorides such as iron chloride (II) and iron (III) chloride, bromides such as iron (II) bromide and iron (II) bromide, iron (II) sulfate, and iron sulfate Inorganic acid salts such as (III), iron nitrate (II), iron nitrate (III), iron acetate (II), iron acetate (II), iron oxalate (III), iron oxalate (III), iron formate The compound can be subjected to the reaction in the form of various salts or coordination compounds such as iron acetylacetone.

Examples of the copper compound include chlorides such as copper (I) chloride and copper (II), bromides such as copper (I) and copper (II) bromide, copper sulfate, copper sulfate, copper nitrate, and nitric acid. Inorganic acid salts such as copper, copper acetate, copper acetate, copper oxalate, copper oxalate, copper formate, acetylacetone copper, etc. The reaction can be carried out in the form of a salt or a coordination compound. Among them, copper chloride (1) and copper chloride (II) are preferable.

 In general, a low catalyst concentration is preferable from an economic point of view, but from the viewpoint of productivity, it should be increased to some extent in a region where the reaction rate has no negative correlation with the catalyst concentration. It is preferable to do so. From these viewpoints, the concentration of palladium is usually 0.001 w or more, preferably 0.01 wt% or more, and usually 10 wt% or less, preferably 5 wt% or less, based on the total weight of the reaction solution as [Pd]. %, But under high concentration conditions, the concentration dependence of the reaction rate behaves differently than under low concentration conditions, and the catalyst efficiency tends to deteriorate. An efficient concentration should be selected from

 The concentration of iron or copper in the reaction solution can be described as a relative concentration to palladium. When the abundances of iron and copper are represented by a molar ratio to palladium, they can be selected in the range of usually 0.01 or more, preferably 0.1 or more, and usually 100 or less and 10 or less. In the region where the iron or copper ion concentration is lower than these ranges, not only the reaction rate is lowered but also the main effect of suppressing Pd precipitation tends to be small, which is not preferable. In addition, the addition of a large amount is not preferable because the reaction itself does not inhibit the solubility in the reaction system tends to decrease.

In this step, it is preferable that a halogen ion, particularly a C1 ion or Brion, be present in the reaction system. Here, “ion” may be in the form of a dissociated ion in the reaction system or in the form of a salt without being dissociated. As a method for causing a halogen ion to be present, it is desirable to use a halogen salt such as chloride or bromide as at least one raw material compound selected from palladium, copper and iron used as a catalyst. Alternatively, a halogen compound can be added to the reaction system. As the halogen compound, an inorganic salt such as NaCl or LiCK SnCl ₂ can be used. The abundance of these halogen ions in the reaction system can be described by the relative concentration to Pd. That is, the range of 0.1 <[C1 and / or Br] / [Pd] <100 (molar ratio) is preferable, and more preferably 0.3 <[CI and / or Br] I [Pd] <50. However, in situations where the halogen concentration is high, the concentration of water in the reactor is low, but there is concern about corrosion of the material of the reactor, so the halogen ion concentration should be set as low as possible so that the catalyst system works. Must. Some of the by-products include catalyst-derived There may be components containing a logen. In that case, it is better to replenish the consumed halogen continuously or periodically, for example in the form of metal salts.

 In the reaction of this step, an excess of the alcohol to be reacted can be used as a solvent, but it is effective to add a solvent other than the alcohol. First, the addition of a solvent can suppress the formation of by-products, in particular, the formation of ethers formed by the addition of alcohols to the olefin moiety. Further, when the alcohols form a two-layer with these other solvents, the catalyst and the product can be separated by phase separation as described above. In particular, in a reaction system using a homogeneous catalyst, separation of the catalyst from the product is a major industrial problem, and it is of great significance that these problems can be avoided. Other solvents different from alcohols include aliphatic and aromatic hydrocarbon solvents and halogenated hydrocarbons. Specific examples include benzene, toluene, xylene, ethylbenzene, pentane, hexane, heptane, octane, cyclopentane, cyclohexane, dichloromethane, chloroform, carbon tetrachloride, dichloroethane, and fluorobenzene. The amount of the solvent to be added to the alcohol is not particularly limited, but is preferably 0.05 or more, more preferably 0.1 or more with respect to the total of the alcohol and the olefin. A weight ratio of 100 or less is preferred, and a weight ratio of 25 or less is more preferred.

 In the first-stage reaction for mainly obtaining acetal or ketone compounds, it can be confirmed that the reaction proceeds if the reaction temperature is 0 ° C. or higher, but the temperature dependence of the reaction of the present invention is large. Therefore, higher temperatures are preferred. However, it is necessary to avoid the conditions for the formation of explosive mixtures, and to avoid the increase of by-products and the polymerization reaction of substrates due to radical auto-oxidation, which tends to proceed in the high-temperature region.The reaction temperature should be selected from these viewpoints. However, in general, the reaction is preferably performed in a temperature range between 20 ° C. and 200 ° C. More preferably, at a temperature of 40 ° C. to 180 ° C., an economically advantageous reaction rate can be obtained.

In this process, oxygen is used, but it is necessary to avoid the danger that oxygen and organic compounds can form explosive mixtures at certain temperatures, certain pressure ranges, and composition ranges. If the oxygen partial pressure is usually 0.001Mpa or more, the reaction proceeds, but if the oxygen partial pressure is low, the reaction rate tends to slow down, and there is a concern that the catalyst may be deactivated. However, in the present invention, 0.01 to 10 MPa Is preferred. If possible, the oxygen partial pressure is more preferably 0.05-5 MPa, but a more preferable pressure is selected from the viewpoint of safety and economy.

 The reaction in this step can be performed according to a general oxidation method. When each component of the catalyst is present in a solution state, the oxidation reaction can be advanced by bringing the olefins into contact with oxygen-containing gas for a specific reaction time in a batch reactor, or a continuous-phase reactor. Accordingly, the oxygen-containing gas and the olefins can be continuously supplied to advance the oxidation reaction. On the other hand, when the catalyst component of the first-stage reaction is immobilized, the above-described liquid-phase reaction can be used. A so-called trickle bed system for supplying oxygen and oxygen can be employed.

 Oxygen is supplied by means of a method in which oxygen-containing gas is made into fine bubbles by stirring blades, a method in which a baffle plate is installed inside the reactor to make oxygen gas fine bubbles, or a method in which oxygen is sprayed into the system at a high linear velocity from a nozzle. Thus, a method effective for dissolving oxygen in the reaction solution system can be adopted.

In addition, in these reactions, water generated when acetal or ketones are formed causes the equilibrium between acetal or ketones and aldehydes or ketones to become aldehydes or ketones. Preference is given to ketones. Since these free carbonyl compounds have higher reactivity to the oxidation reaction than the alcohol adduct, they are susceptible to sequential oxidation. Therefore, it is preferable to remove water generated in the system as much as possible outside the system. The amount of water is preferably maintained at 50% by weight or less, more preferably at 20% by weight or less. Examples of the method include a method in which molecular sieves such as zeolite, an anhydrous metal salt that adsorbs water, and the like coexist, a method in which a component azeotropic with water is added and distillation is removed, and a method in which a gas containing or not containing oxygen is used. There are methods such as a distillation method and a method of adding a compound that reacts with water and is converted into a compound that does not adversely affect the reaction, for example, a metal alkoxide. When the reaction solution after the oxidation reaction is in a pressurized state, the pressure may be released to some extent to lower the pressure. When the boiling points of the raw material components and products are significantly different from those of the reaction solvent and are low boiling points, those low boiling components can be directly separated from the reaction solution by distillation. If the boiling points of the raw material components and the product are higher than the boiling point of the reaction solvent, a solvent that forms a two-phase with the reaction solvent is added, and the liquid-liquid mixture is added so that the catalyst component is contained in one phase. By performing phase separation, the raw material can be recovered from the solvent phase containing almost no catalyst, and the product can be selectively removed. If a small amount of catalyst component is mixed into the product after phase separation, the remaining amount of catalyst component can be reduced to a negligible level by performing extraction and separation two or more times. After phase separation, a certain level of raw material recovery and distillation operation to recover the product can be performed, the residual catalyst concentration can be increased to some extent, and then re-extraction can be performed, making it more economical and efficient. The approach considered to be considered should be taken. The catalyst in the alcohol phase separated by the phase separation can be recycled and used in the reactor in the oxidation step.

 Further, in the reactor, water is generated by sequential oxidation that occurs in a small amount. It is preferable to remove the generated water to the outside of the system as much as possible. Nevertheless, if there is a halogen component such as C1 in the system, there is a great concern about reactor corrosion. Therefore, it is necessary to use materials with high resistance to corrosive acids such as hydrogen chloride where necessary.

 In the region where the reaction pressure is not too high, a material such as glass, ceramic, or fluororesin can be used.When the reaction pressure is high, those generally used as corrosion-resistant reaction containers, that is, various types of It is preferable to use a container made of a stainless alloy, particularly what is commonly called Hastelloy, an alloy containing titanium, an alloy containing zirconium, or a container in which these alloys are applied to the surface and pressed. In particular, the reactor has a high possibility of corrosion. However, if a stationary tank or a separation tank is provided, this part is highly likely to corrode. Furthermore, in the case of distillation of the oil phase containing the product, if the catalyst component remains, the halogen component may be concentrated and the possibility of corrosion is high. It is preferable to use a corrosion-resistant material for these main containers and their associated pipes within the economically acceptable range, depending on the high possibility of corrosion.

The main component of the compound obtained in the reaction of this step is an acetal or ketal in which the olefin moiety has been acidified and further reacted with an alcohol. Specifically, when acrolein or its acetal, 2-vinyl-1,3-dioxane (VDO) is used as a raw material, the main product is malonaldehyde bis (1,3-dioxane-1-yl). ) Acetal (DAC) and malonaldehyde mono (1,3-dioxane-12-yl) acetal (MA C) are obtained. Other than these main components In addition, 3-hydroxypropyl 1,3-dioxacyclohexyl-2-ylhetanoate (PDE), 2-hydroxyethyl-1,3-dioxane (HDO) and the like are obtained. All of these compounds, as well as acetal as the main component, can be converted to 1,3-propanediol, the polyhydric alcohol of the target compound, by the hydrolysis and reduction reaction in the second step below. it can.

 In the above reaction, oxygen is not involved, and the ether directly inserted into the olefin moiety may be observed as a by-product. Specifically, when acrolein or its acetal, 2-pinyl-1,3-dioxane (VDO) is used as a raw material, 2- (6-hydroxy-13-oxahexyl) —1 , 3-dioxane (HE DO). Alcohols that are present as an essential component in the reaction system are not at all inert to the oxidation reaction. Compounds in which alcohol has been oxidized may also be observed.

 However, many of these by-products, along with the desired product, undergo hydrolysis and reduction in subsequent steps to be converted back to alcohols or decomposed into low-boiling compounds. In general, in the oxidation reaction, the sequential oxide obtained as a by-product often has a high boiling point, and often consumes a large amount of energy when it is removed by distillation. By-products can be converted into active ingredients or broken down into compounds that are easy to separate, making it possible to construct industrially very efficient processes.

On the other hand, when the batch reaction is repeated for a long time, or in a continuous reaction, the components derived from the above-mentioned oxide olefins of the alcohols are accumulated in the alcohol phase containing the catalyst component. There is also. In order to operate the process stably, it is necessary to control the overall mass balance. Therefore, it is necessary to remove a part of the alcohol phase containing the catalyst out of the system and supply a new catalyst raw material liquid in consideration of the generation rate of these impurities and the generation rate of the sequential oxidation component. At this time, it is necessary to recover the catalyst components removed from the system if the removal rate is large and the economic burden is large. The method is not limited, but methods such as removal of organic matter, washing, and recovery of metal components are effective. Also, when the separation solvent is recovered from the organic phase containing the product separated in two phases, the accumulation of impurities may occur in the same manner. In this case, a part of the separation solvent is removed outside the system. It is necessary to replenish new separation solvent.

· <Deprotection process>

 The acetal, Z or ketal compound obtained by oxidizing an olefin having a protecting group that has undergone the protection reaction in the above step must be converted to a carbonyl group by deprotection. As the deprotection method, a known method is used depending on the carbonyl group-protecting group formed in the protection step.

 By deprotection, a compound containing a carbonyl group and the protecting agent used in the protecting step can be obtained.The protecting agent obtained in this step is separated and recovered, and when it can be used as it is as a protecting agent, it is protected. Can be recycled to the process. If the protective agent cannot be used as it is, it can be recycled as a protective agent through an appropriate reaction and recycled.

 The deprotection step can be performed after the Kanei decomposition step depending on the type of the protecting group. When the presence of the protecting group may hinder the hydrolysis step, or when the protecting group is degraded in the hydrolysis step and may not be converted to a hydroxyl group in the reduction step, or if the acetal and the acetal generated in the oxidation step by the deprotection step If there is a possibility that Z or ketal cannot be converted to a hydroxyl group in a subsequent step, perform it before the hydrolysis step. If the above effects are not exerted on the hydrolysis step, either deprotection or hydrolysis can be performed first.

Further, if the protecting group is converted to a hydroxyl group in the hydrolysis or reduction step without deprotection, the deprotection step may be omitted. Specifically, when a carboxylic acid is esterified in the protection step, the ester is reduced and converted to a hydroxyl group without deprotection and conversion back to the carboxylic acid. In general, the reduction of the ester is often easier than the reduction of the carboxylic acid, and in such a case, it is preferable to omit the deprotection step. Furthermore, if the protecting group generated in the protection step is an acetal and / or ketal, it is converted to a carbonyl group in the hydrolysis step together with the acetal and Z or ketal generated in the oxidation step. The steps can be performed simultaneously. This means that the number of reactors and the like in the process is reduced, and construction costs are reduced, which is industrially preferable.In addition, deprotection of acetal and / or ketal is a part of hydrolysis. explain in detail.

<Hydrolysis step>

 The hydrolysis step is a step of hydrolyzing the acetal and Z or ketal obtained in the above-mentioned oxidation step or deprotection step and converting them into a carbonyl group.

 The hydrolysis is usually carried out in the presence of a catalyst, which can be an acid. In this case, the acid used is a mineral acid such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, a Lewis acid such as lanthanoid triflate, a polyacid such as heteropoly acid, a solid acid such as an ion exchange resin, zeolite, or clay. can do. Solid acids are convenient because of the ease of product separation. The addition amount of the acid is effective even in a very small amount and is not particularly limited, but is preferably 0.001% by weight or more, more preferably 0.01% by weight or less, and preferably 100% by weight or less with respect to the substrate. Further, it is not more than 70% by weight, especially not more than 60% by weight.

The amount of water used for the hydrolysis is usually above the stoichiometric amount required to degrade acetal and Z or ketal. However, when acetal and Z or ketal are hydrolyzed, aldehyde and Z or ketone are formed, and this reaction is an equilibrium reaction. Therefore, a large amount of water is required to overcome the equilibrium reaction. The problem of adding such a large amount of water is that it increases the cost of removing water from the product, and that amount should be discussed from an economic point of view. Specifically, the amount of water in the reaction system is usually at least l vol%, preferably at least 5 vol%, and usually at most 99 vol%, preferably at most 8 vol%, based on the entire reaction volume. It is within the range of O vol% or less. The molar ratio of the raw material and water in the reaction system in the initial stage of the reaction is not particularly limited, but may be in the range of 1/1 to 1/100. Even in the above range, 1/1 to 1 /% is preferable, and the range of 1 / 1.2 to 1/90 is particularly preferable. When the alcohol or carbonyl compound produced by the hydrolysis has a lower boiling point than water, the reaction can be carried out while distilling off the alcohol or carbonyl compound, which is advantageous in that the amount of water used is reduced. is there. In order to shift the equilibrium, the same effect can be obtained by using a solvent in which the product haponyl compound is soluble as the solvent and extracting the carbonitrile compound with the solvent during the reaction and leaving it outside the system. . Any solvent may be used as long as it does not undergo alteration by the acid or the reducing agent. When the reaction temperature of the hydrolysis is 0 ° C. or higher, it can be confirmed that the reaction proceeds. However, in the present invention, a higher temperature is preferable because the reaction has a large temperature dependency. Generally, the hydrolysis reaction is preferably performed in a temperature range between 20 degrees and 200 degrees. More preferably, at a temperature of 40 ° C. to 180 ° C., an economically advantageous reaction rate can be obtained.

 The reaction in this step can be performed by a general method. When each component of the catalyst is present in a solution state, the reaction can be carried out by contacting the substrate with water for a specific reaction time using a batch reactor. In addition, using a continuous-phase reactor, water and substrate can be continuously supplied to advance the reaction. On the other hand, when the catalyst component of the present invention is immobilized, the above-mentioned liquid phase reaction can be used, and a fixed bed is filled with a catalyst, and the corresponding substrate and water are converted to a liquid phase state. A so-called trickle bed system can be used for supply.

 In this step, the alcohol used in the oxidation step is generated, and can be recovered and recycled to the reactor in the oxidation step. In addition, if acetals and ketals were used as protecting groups in the protection step, and the deprotection step was omitted, the alcohol used in the synthesis of acetals and ketals from aldehydes and ketones in the protection step was also recovered. Is done. This alcohol can be recycled to the reactor that is synthesized from the kettle and the base of the protection process.

 If the alcohol used in the oxidation step and the alcohol used in synthesizing the acetal and ketal in the protection step are the same, there is no need to separate these alcohols, and the protection step is performed according to the required ratio. It can be recycled to the reactor and the reactor in the oxidation step.

 If the above two alcohols and the polyhydric alcohol as the target product are all the same or one of them is the same, there is no need to separate the alcohols or the number of types to be separated is reduced, simplifying purification. This is an industrially advantageous process. When the reaction solution after the hydrolysis step is in a pressurized state, the pressure may be released to some extent to lower the pressure. For separation of the target product from the catalyst component, water and by-products, general operation methods such as distillation separation, extraction separation, crystallization separation, sedimentation separation, and filtration separation can be used.

In addition, the by-products generated by the separation or the target product containing by-products are It can also be returned to the reactor. For example, by-products having a higher boiling point than the target compound at the time of distillation separation undergo hydrolysis and the like again, undergo decomposition, etc. Improve overall conversion and alcohol recovery.

<Reduction process>

 The reduction step is a step in which the carbonyl compound obtained in the hydrolysis step is reduced and converted into a polyhydric alcohol.

 As the reducing agent to be used in the reduction reaction, there are many known reducing agents for carbonyl groups, commercially available ones, and the like, and any of them can be arbitrarily selected. As described above, the hydrolysis step and the subsequent reduction step are desirably performed simultaneously in the same reactor. Therefore, a reducing agent that does not impair the reducing ability of acid and water is desirable. Catalytic reduction using hydrogen as a reducing agent is more desirable because of its economy and ease of separation.

 When hydrogen is used as the reducing agent, the reaction proceeds if the partial pressure of hydrogen is greater than 0.001 MPa, but if the hydrogen partial pressure is low, the reaction rate slows down and there is a concern that the catalyst may be deactivated. Must be determined in relation to temperature and catalyst concentration. Usually, it is at least 0.05 OlMPa, preferably at least 0.05 MPa, more preferably at least IMPA, and usually at most 50 MPa, preferably at most 20 MPa, more preferably at most lOMPa.

 There are many known catalytic reduction catalysts, such as noble metals such as Raney nickel, platinum, rhodium, palladium, and ruthenium, and those which are supported on a carrier such as carbon, silica, and zeolite. However, you can choose any of them. In particular, a catalyst containing ruthenium as a main component is preferable because it has few side reactions. The amount of these catalysts is effective even in a very small amount and is not particularly limited, but is preferably 0.0001 to 则 weight ratio to the substrate, more preferably 0.0001 to 70 weight ratio, particularly preferably 0.1 to 70 weight ratio. 01% to 50% by weight.

In the reduction reaction, it can be confirmed that the reaction proceeds when the reaction temperature is 0 ° C. or higher, and an industrially sufficient reaction rate can be obtained even at around room temperature. Even at higher temperatures, high reactivity is obtained, but the increase in by-products due to the hydrogenolysis of aldehydes, acetal, ketones, ketals, and alcohols, which tends to proceed in the high temperature range, is avoided The reaction temperature should be selected from these viewpoints. Generally, the reduction reaction is preferably performed in a temperature range between 10 degrees and 200 degrees. More preferably, at a temperature of 25 ° C. to 180 ° C., an economically significant reaction rate can be obtained.

 The reaction in this step can be performed by a general method. When each component of the catalyst is present in a solution state, the reaction can be carried out by bringing the substrate into contact with a gas containing water and hydrogen for a specific reaction time in a batch reactor, or by a continuous phase reactor. The reaction can be advanced by continuously supplying a gas containing water and hydrogen and a substrate. On the other hand, when the catalyst component of the present invention is immobilized, the above-described liquid phase reaction can be used, or the fixed bed is filled with the catalyst, and the corresponding substrate, water, A so-called trickle bed system for supplying hydrogen and hydrogen can be employed. · The reaction after the reduction reaction 場合 If the pressure is high during the night, the pressure may be released to some extent to lower the pressure. For separation of the target product from the catalyst component, water and by-products, general operation methods such as distillation separation, extraction separation, crystallization separation, sedimentation separation, and filtration separation can be used. Among the polyhydric alcohols used as raw materials for polyesters, the presence of carbonyl compounds as impurities often poses a problem.If these cannot be completely removed by a simple operation such as distillation, the above-mentioned method is used. An optimal purification method that combines operations is adopted. If they are difficult, purify the product to reduce the concentration of carbonyl compounds in the product by further reducing at high pressure and high temperature.

 In addition, the by-product generated by the separation or the polyhydric alcohol containing the by-product can be returned to the reactor. By-products having a higher boiling point than the target polyhydric alcohol at the time of distillation and separation are subject to decomposition, etc. by hydrolysis and hydrogenation again, and some are converted to the objective polyhydric alcohol, and It may be a product, and the average boiling point of the entire product is reduced, so that the energy cost required for distillation is low. The relationship between the hydrolysis angle and the reduction process>

In the present invention, a method in which the hydrolysis step and the reduction step are performed in separate reactors, or a method in which water is added in the same vessel to carry out hydrolysis, and then a reducing agent is introduced to perform reduction, is used. Although it is possible to employ, it is desirable that the hydrolysis reaction and the subsequent reduction reaction be carried out simultaneously in the same reactor in the presence of water and a reducing agent. Because Hydrolysis of acetal and / or ketal produces aldehyde and / or ketone, which is an equilibrium reaction and requires a large amount of water to overcome the equilibrium reaction.

 The problem of adding such a large amount of water is that it increases the cost of removing water from the product. However, by simultaneously performing hydrolysis and subsequent reduction in the same reactor, the aldehydes and / or ketones that are hydrolyzed are immediately reduced to alcohols, and escape from the constraints of equilibrium. Since the water is biased toward the production system, the amount of water to be added can be reduced. In this case, the amount of water used for the hydrolysis may be a stoichiometric amount necessary for hydrolyzing the substrate. Of course, it may be used in excess. A solvent may be added in addition to water.

 When a solvent that forms two layers with alcohol is used to separate the product and the catalyst after the above-described oxidation step, the product is obtained in a state where the product is dissolved in the solvent. In a state where this product is dissolved in a solvent, hydrolysis and reduction can be carried out by contacting with water or hydrogen. In this case, since the alcohol generated by the deprotection is the alcohol used in the oxidation step, it is phase-separated from the solvent. When acetal, and Z or ketal are used as the protecting group, alcohol is generated by hydrolysis, and the target product is also a polyhydric alcohol. After the oxidation reaction, the solvent is distilled off from the state in which the product is dissolved in the solvent, or the product is removed by distillation or the like, followed by deprotection, hydrolysis, and reduction. After the reduction, the method of phase-separating the product or the like may be simple and cost-effective in some cases. In addition, this method facilitates separation of the unreacted carbonyl compound from the target polyhydric alcohol, and has the effect of increasing the purity of the polyhydric alcohol.

A preferred embodiment in the case where the hydrolysis step and the reduction step are performed simultaneously will be described. The catalyst used for the hydrolysis reaction, the reducing agent used for the reduction reaction, the catalyst used for the reduction, and the added solvent are all those that are not altered by acids, water, or hydrogen, or whose catalytic ability is not impaired. desirable. In this case, the hydrolysis catalyst and the catalytic reduction catalyst described above may be added as separate catalysts or as a physical mixture thereof.For example, catalytic reduction using a solid acid such as zeolite as a carrier may be used. It may be added as a dual type of catalyst having a chemical bond with each other, such as a supported noble metal supported on it. Metals containing Pt, Ru, Pd, etc. It is known that some catalysts function as both an acid and a hydrogenation catalyst in the presence of hydrogen. By using such a catalyst, hydrolysis and reduction reactions are performed with a single catalyst. be able to.

 The reaction can be carried out by bringing the substrate into contact with a gas containing water and hydrogen for a specific reaction time in a batch reactor, and then proceeding the reaction with a continuous phase reactor. Can be supplied continuously to advance the reaction. On the other hand, when the catalyst component of the present invention is immobilized, the above-described liquid phase reaction can be used. A so-called trickle bed system for supplying, and hydrogen can be employed. When acetals and ketyls are used as protecting groups in the protection step, if the hydrolysis and reduction reactions are performed simultaneously in the protection step, deprotection reactions are also performed, and the acetals and ketals are converted to aldehydes. In addition, the alcohol used in the synthesis from ketone, the alcohol used in the oxidation step, and the alcohol which is the target compound of the present invention are produced. If the three types are different, they can be separated and recycled to each process.If they are all the same or one of them is the same, there is no need to separate the alcohols or the types to be separated are reduced, and the purification This leads to simplification and an industrially advantageous process.

 Specifically, for example, when acrolein is used as a raw material, 1,3-propanediol is used as a protective agent in the protection step, and 1,3-propanediol is used as an alcohol in the oxidation step, the deprotection step, the hydrolysis angle By performing the process and the reduction process in parallel in the same reactor, all become 1,3-propanediol, and there is no need to separate alcohols.

As described above, the basic components of the reaction system of the present invention have been described. However, these components are conditions suitable for efficient oxidation, hydrolysis, and reduction of olefins. For each reaction step, it is also possible to increase the activity and reactivity by adding another component. That is, additives having an effect of promoting the oxidation reaction, for example, addition of compounds such as copper compounds, alkalis, alkaline earth metals and rare earths, suppression of side reactions by a radical trapping agent, and increase of dissolved oxygen concentration in a solution. Solvent, supercritical fluid, increased mechanical stirring strength, immobilize active ingredients, Even a method of improving the dispersibility of the catalyst component is within the scope of the present invention as long as it includes the above-described catalyst component of the present invention.

 In the present invention, a process for producing 1,3-propanediol using as a olefin a lactone and its acetal, particularly 2-vinyl-1,3-dioxane as a substrate, is a process in which the product is a polyester. This process is particularly useful industrially because it is useful as a raw material. For the production of polyester from 1,3-propanediol, a general production method described in WO9823662, WO9815559 and the like can be used. '

 Example

 Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

In Examples and Comparative Examples, the following abbreviations represent the following compounds.

VDO: 2-vinyl-1,3-dioxane

HD O; 2-hydroxyethyl-1,3-dioxane

MA C; malonaldehyde mono (1,3-dioxane-1-yl) acetal

D A C; Malonaldehyde bis (1,3-dioxane-2-yl) acetal

HE DO ; 2— （6—ヒドロキシー 3—ォキサへキシル） 一 1, 3—ジォキサン

HE DO; 2- (6-hydroxy-3-oxahexyl) -1,3-dioxane

PDE; 3-hydroxypropyl 1,3-dioxacyclohexyl 2-yl

13PD; 1,3-propanediol

 In Examples and Comparative Examples, the selectivity during the oxidation reaction was calculated by the following equation. Target product selectivity (%) = (Total number of moles of HDO, MAC, DAC, PDE) / (Total number of moles of all products)

 DAC selectivity (%) = (total number of moles of DAC) Z (total number of moles of HD〇, MAC, DAC, PDE)

 HEDO selectivity (%) = (total number of moles of HEDO) Z (total number of moles of all products)

 (Reference example) Protection reaction of carbonyl group of olefins having ethylenic double bond with carbonyl group in the same molecule

 (Reference example 1)

Acrolein and 1,3-propanediol were mixed at an arbitrary ratio (molar ratio) so that the total amount became 5 g, and 175 mg of acidic ion exchange resin, Amberlystl5 (dry) (manufactured by Rohm and Haas Co.) was added. (Only one example (a) was in an ice bath for 60 minutes), and after 20 minutes, it was analyzed by gas chromatography. Table 1 shows the results. Charge (mol) ratio VDO yield (based on ACR);

 (1,3 pro pan e dioi / acroie in)%

 3.91 80.7

 3.12 79J

 1.48 71.8

 0.92 58.0

 0.33 27.1

 0.26 21.5

 1.50 '82.0 a = 0 ° C 60min

(Reference Example 2)

 A glass column with a jacket (inner diameter: 11 mm, length: 120 mm) was filled with glass beads from the entrance side by about 7 m1, then 175 mg of acidic ion exchange resin (Amberlystl5) was mixed with glass particles of the same particle size to make the whole 5 m1. The layer was packed, and the glass beads were packed until the column became short. Then, a solution of acrolein and 1,3-propanediol in a molar ratio of 1: 1.5 was prepared by an LC pump, and this solution was 0.494 g / The flow was mim (contact time: about 7 minutes). Water at a predetermined temperature was separately flowed through the jacket so that the temperature of the column was maintained at 25 ° C. The liquid was collected at the outlet and analyzed by GC. As a result, the yield of VD0 was 64.8%.

 (Reference example 3)

 Amberlystl5 was packed with 3 m1 without mixing with glass particles, flowed at a flow rate of 0.29 g / mim (contact time about 6 minutes), and the reaction was carried out in the same manner as in Reference Example 2 except that the jacket temperature was set to 0 ° C. As a result, the yield of VD0 was 78.3%.

 (Example 1)

 To a mixture of acrolein and 1,3-propanediol in a molar ratio of 1: 3, add 2 wt% of an acidic ion exchange resin (Amberlyst 15 dry) to the mixture, stir for 20 minutes at room temperature, and filter the catalyst. did. To the reaction mixture, a 4-fold volume of methylene chloride was added for extraction. After liquid separation, the methylene chloride layer was dried over anhydrous magnesium sulfate, and then the desiccant was filtered off and distilled. The desired 2-vinyl-1,3-dioxane (VD〇) was obtained in 70% yield based on acrolein.

Na ₂ PdCl ₄ 0.1 touch 1, CuCl 0.1 ol, FeCl ₃ 0.1 t ol 6 g 1,3-propanedi To the solution completely dissolved in all, was added VD09.7 alcohol obtained by the above reaction. This solution was placed in a stainless steel autoclave equipped with a Teflon inner cylinder and a stirrer, and 6 g of benzene was added. The inside of the autoclave was replaced with oxygen, and the oxygen pressure was adjusted to 0.7 MPa. It was placed in a water bath at 80 ° C and stirred. At this time, the pressure of the consumed oxygen was replenished so that the pressure became constant. Twenty-five minutes after the start of stirring, the mixture was rapidly cooled in an ice bath with stirring. The reaction mixture was analyzed by gas chromatography. The conversion of VDO was 98.2%, with 79.4% selectivity for the target compound (75.0% DAC selectivity) and 7.0% leak selectivity.

 Here, the object refers to HDO, MAC, DAC, and PDE, and the same applies to the following examples. The benzene layer was separated, and benzene was distilled off from the benzene layer, followed by purification to obtain a mixture of the desired products. 0.25 g of zeolite USY (silica / alumina ratio: 50), 0.38 g of 5% Ru / C, and 2.5 g of water were added to the mixture, and the mixture was placed in an autoclave. After hydrogen replacement, the hydrogen pressure was adjusted to 0.9 MPa, and the mixture was placed in an 80-liter bath and stirred until hydrogen was not consumed and the pressure did not decrease, thereby performing a hydrolysis reaction and a reduction reaction. It took about 30 minutes during this time. The conversion of HD 0 and DAC was 99.6%, and the selectivity of 13 PD was 99.6%.

 (Example 2)

19 mmol of acrolein was added to a solution obtained by completely dissolving 0.1 g of Na ₂ PdCl _4, 0.1 μl of CuCl, and 0.1 μl of FeCl _{3 in} 1,3-propanediol, and stirred for 30 minutes. This solution was placed in a stainless steel autoclave equipped with a Teflon inner cylinder and a stirrer, and 6 g of benzene was further added. After the inside of the autoclave was replaced with oxygen, the oxygen pressure was increased to 0.7 MPa. It was put into a bath at 80 ° C and stirred. At this time, the pressure of the consumed oxygen was replenished so that the pressure became constant. Twenty-five minutes after the start of stirring, the mixture was rapidly cooled in an ice bath with stirring. The reaction mixture was analyzed by gas chromatography. The conversion of acrolein was 100%, with 77.5% selectivity for the target compound (73.9% for DAC) and 14.4% for HED0 selectivity.

The benzene layer was separated, and benzene was distilled off from the benzene layer, followed by purification to obtain HD 0 (2.6 tmol) and DAC (9.96 tmol). 0.25 g of zeolite USY (silica / alumina ratio: 50), 0.38 g of 5% Ru / C, and 2.5 g of water were added to the mixture, and the mixture was placed in an autoclave. After hydrogen replacement, the hydrogen pressure was set to 0.9 MPa, and the temperature was reduced to 80 ° C. The hydrolysis and reduction reactions were carried out by stirring the mixture in a vacuum bath until hydrogen was not consumed and the pressure did not decrease. It took about 30 minutes during this time. The conversion of HD 0 and DAC was 99.6%, and the selectivity of 13 PD was 99.6%.

 (Example 3)

The procedure described in Example 2 was repeated except that PdCl ₂ (CH ₃ CN) ₂ was used instead of Na ₂ PdCl ₄ , the amount of 1,3-propanediol was 10 g, and VDO 15.9 tol was used instead of acrolein. The reaction was performed in the manner described. The conversion of VDO was 100%. The selectivity for the target product was 65.7% (DAC selectivity 78.4%) and HED0 selectivity 27.9%. The conversion rate of HD〇 and DAC was 99.5%, and the selectivity of 13 PD was 99.7%.

 (Example 4)

 The reaction was carried out in the same manner as in Example 2 except that 9.7 〇ol of VD was used instead of acrolein and hexane was used instead of benzene. The conversion of VDO was 100%. The selectivity of the target compound was 73.0% (DAC selectivity 73.3%) and HED0 selectivity was 14.4%. The conversion of HDO and DAC was 99.6%, and the selectivity of 13 PD was 99.6%.

 (Example 5)

 The reaction was performed in the same manner as in Example 2 except that VD09.7 marl was used instead of acrolein, the amount of 1,3-propanediol was changed to 1 g, and 10 g of dichloroethane was used instead of 6 g of benzene. The conversion of VDO was 85.8%, and the selectivity for the target product was 85.1% (DAC selectivity 71.6%) and HED0 selectivity was 0.9%. The conversion of HDII and DAC was 99.4%, and the selectivity of 13PD was 99.5%.

 (Example 6)

 VD09.7 bandol was used instead of acrolein, the amount of 1,3-propanediol was 2 g, ethanol was used instead of 6 g of benzene, and cooling was performed 10 minutes after the start of stirring. The reaction was performed in the same manner as in Example 2. The conversion of VDO was 100%, and the selectivity for the target product was 75.2% (DAC selectivity 71.3%) and HED0 selectivity 1.1%. The conversion of HDO and DAC was 99.6%, and the selectivity of 13 PD was 99.6%.

(Example 7)

The reaction was carried out in the same manner as in Example 3 except that VD09.7 marl was used instead of acrolein, the amount of 1,3-propanediol was changed to 2 g, and methanol was used instead of 6 g of benzene. The conversion rate of VDO is 98.7%, and the selectivity of target substance is 68.9% (DAC selectivity) 74.3%), and the selectivity of HEDO was 4.6%. The conversion of HDO and DAC was 99.6%, and the selectivity of 13 PD was 99.6%.

 (Example 8)

 Example 2 was repeated except that acrolein was replaced with VD〇9.7 propyl alcohol, the amount of 1,3-propanediol was adjusted to 2 g, the amount of benzene was adjusted to 8 g, and cooling was performed 35 minutes after the start of stirring. Reacted similarly. The conversion rate of VDO was 100%, the target substance selectivity was 87.9¾ (DAC selectivity 83.4%), and HEDO selectivity was 3.5%. The transfer ratio of HDO and DAC was 99.6%, and the selectivity of 13 PD was 99.6%.

 (Example 9)

 The reaction was carried out in the same manner as in Example 2 except that VD09.7 was used instead of acrolein, FeC13 was not used, and the mixture was cooled 60 minutes after the start of stirring. The conversion of VDO was 96.1%, the selectivity for the target compound was 59.1% (DAC selectivity 69.1%), and the selectivity for HED0 was 27.5%. The conversion of HDO and DAC was 99.6%, and the selectivity of 13 PD was 99.6%. (Example 10)

 The reaction was carried out in the same manner as in Example 2 except that VD09.7 was used in place of acrolein and 2 g of tetraethoxysilicon was dissolved in benzene added during the oxidation reaction. The conversion of VDO was 97.8%, with 84.5% selectivity for the target compound (MC selectivity 78.7%) and HED0 selectivity 2.9%. The conversion of HDO.DAC was 99.6%, and the selectivity of 13 PD was 99.6%.

 (Example 11)

 The reaction was carried out in the same manner as in Example 9 except that the amount of 1,3-propanediol was changed to 4 g, the amount of benzene was changed to 8 g, and cooling was performed 15 minutes after the start of stirring. The conversion of VDO was 97.2%. The selectivity for the target compound was 91.8% (DAC selectivity 80.4%) and HED0 selectivity was 0.6%. The conversion of HDO and DAC was 99.6%, and the selectivity of 13 PD was 99.6%.

 (Example 12)

Same as Example 2 except that VD09.7 alcohol was used in place of acrolein, and 0.5 g of 2,6-di-t-butyl-4-methylphenol, a polymerization inhibitor, was dissolved in benzene added during the oxidation reaction. Reacted. The conversion rate of VDO is 98.1%. Selectivity 77.5% (DAC selectivity 72.0%) and HEDO selectivity 14.4. The conversion of HDO and DAC was 99.6%, and the selectivity of 13 PD was 99.6%.

 (Example 13)

Na ₂ PdCl ₄ 0.lmmoK CuCl 0.1Clol, FeCl ₃ 0.limoi completely dissolved in 6 g of 1,3-propanediol, add 6 g of benzene, stainless steel with Teflon inner cylinder and stirrer Into an autoclave. After the inside was replaced with oxygen, it was put into a water bath at 80 ° C and left in the autoclave until the temperature reached 80 ° C. Then, VDO10 was added, the oxygen pressure was adjusted to 0.7 MPa, and the mixture was stirred. At this time, the pressure of the consumed oxygen was replenished so that the pressure became constant. Ten minutes after the start of stirring, the mixture was cooled and the reaction mixture was analyzed by gas chromatography. The conversion of VDO was 100%, and the selectivity for the target compound was 78.4% (DAC selectivity 76.0%) and HED0 selectivity was 8.4%. Thereafter, hydrolysis and hydrogenation were carried out in the same manner as in Example 2. The conversion of HDO and DAC was 99.6%, and the selectivity of 13 PD was 99.6%.

 (Example 14)

 The reaction was carried out in the same manner as in Example 2, except that VD09.7 was used instead of acrolein and cesandastate was used instead of zeolite USY. The conversion of HDO and DAC was 91.0%, and the selectivity of 13 PD was 96.5%.

 (Comparative Example 1)

The reaction was performed in the same manner as in Example 2 except that VD09.7 t ol was used in place of acrolein, and Na ₂ PdCl ₄ 0.1 ol, CuCl 0.1 t ol, and FeCl ₃ 0.1 mmol were not added. As a result, no DAC was generated and the raw material was recovered.

 (Comparative Example 2)

 The reaction was carried out in the same manner as in Example 2 except that VD09.7 was used instead of acrolein and nitrogen was used instead of oxygen. HEDO only got. Industrial applicability

 ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to manufacture a polyhydric alcohol from olefins having a carbonyl group at a high conversion rate and a high selectivity while suppressing a side reaction, which has high industrial utility value.

Claims

The scope of the claims 1. The olefins having an ethylenic double bond having a carbonyl group and / or a protecting group in the same molecule are reacted with oxygen and alcohol to obtain a reaction product containing acetal and Z or a ketal compound, A method for producing polyhydric alcohols by subjecting the acetal and / or ketal compound to hydrolysis and reduction. 2. Olefins having a carbonyl group and an ethylenic double bond in the same molecule are reacted with a protecting agent to protect the carbonyl group. Are reacted with oxygen and alcohols to obtain the corresponding acetal and Z or ketal compound, and then the acetal and Z or ketal compound are deprotected, hydrolyzed, and reduced to obtain polyhydric alcohols. How to make. 3. The polyhydric alcohol according to claim 1, wherein the carbonyl group and Z or a protecting group thereof are groups selected from an aldehyde group and an acetal group thereof, a ketone group and a ketal group thereof, a hydroxyl group, and an ester group containing a lactone. Manufacturing methods. 4. The method according to claim 1 or 2, wherein the olefins are compounds selected from a, J3 unsaturated aldehydes and acetals thereof, 、, unsaturated ketones and ketones, ひ, β-unsaturated carboxylic acids and esters thereof. 3. The method for producing a polyhydric alcohol according to 3. 5. The method for producing a polyhydric alcohol according to claim 4, wherein the olefins are acrolein and / or acetals thereof. 6. The olefin is an acetal of acrolein, and is an acetal selected from 2-vinyl-1,3-dioxolan, 2-vinyl-1,3-dioxane and 2-vinyl-1,3-dioxepane. 3. The method for producing polyhydric alcohols according to 1.). 7. The method for producing a polyhydric alcohol according to claim 4, wherein the olefins are acrylic acid and Z or an ester thereof. 8. The method for producing a polyhydric alcohol according to any one of claims 1 to 7, wherein the alcohol is a diol. 9. The method for producing a polyhydric alcohol according to any one of claims 1 to 8, wherein when the olefins are reacted with oxygen and alcohols, a catalyst containing palladium and further containing copper, Z or iron is used. . 10. The method for producing a polyhydric alcohol according to any one of claims 1 to 9, wherein a halogen ion is present in the reaction system when the olefin is reacted with oxygen and an alcohol. 11. The method for producing a polyhydric alcohol according to claim 10, wherein at least one selected from palladium, copper, and iron used as a catalyst component is supplied as a halogen salt. 12. The polyhydric alcohol according to any one of claims 1 to 11, wherein when the olefin is reacted with oxygen and an alcohol, a solvent that forms a two-layer with the alcohol is present in a reaction system. Manufacturing method. 13. The production of a polyhydric alcohol according to claim 12, wherein the solvent forming the two layers with the alcohol is selected from an aromatic hydrocarbon, an aliphatic hydrocarbon and a hydrogenated hydrocarbon. Method. 1 4. When producing polyhydric alcohols by hydrolyzing and reducing acetals and Z or ketal compounds obtained by reacting the above olefins with oxygen and alcohols, the hydrolysis and reduction reactions are the same. The method for producing a polyhydric alcohol according to any one of claims 1 to 13, which is performed in a vessel. 15. The method for producing a polyhydric alcohol according to any one of claims 2 to 14, wherein the deprotection, hydrolysis, and reduction of the acetal and Z or the ketal compound are performed in the same reactor. 16. The method for producing a polyhydric alcohol according to claim 14 or 15, wherein a zeolite having a noble metal supported thereon is used as a catalyst when the hydrolysis and the reduction reaction are performed in the same reactor. 17. The method for producing a polyhydric alcohol according to any one of claims 1 to 16, wherein the polyhydric alcohol produced is 1,3-propanediol. 1 8. A polyester obtained using the polyhydric alcohol obtained by the method according to any one of claims 1 to 17.