JPH08301814A - Aliphatic tetraester compound and method for producing the same - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a low molecular weight polyester compound having an alkoxylcarbonyl group at both ends and a method for producing the same. [Structure] An aliphatic tetraester compound represented by the following general formula (1). Embedded image (Wherein R ¹ represents an alkyl group and R ² represents a divalent aliphatic group) In the method for producing the aliphatic tetraester compound represented by the general formula (1), the following general formula (2) CH ₂ = CHCOOR ¹ (2) (wherein R ¹ represents an alkyl group), and an acrylic acid alkyl ester represented by the following general formula (3) HO—R ² —OH (3) (wherein R ² is a divalent group). An aliphatic diol represented by (which represents an aliphatic group) and carbon monoxide are reacted in the presence of a catalyst composed of a complex of cobalt carbonyl and a pyridine base and hydrogen.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel aliphatic tetraester compound and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, a method for producing an aliphatic polyester by subjecting an aliphatic dicarboxylic acid or its alkyl ester and an aliphatic diol to a condensation reaction has been widely used. In such a method, it is very difficult to obtain a low molecular weight polyester in a high yield, and the obtained polyester has a structure having a free carboxyl group or a free hydroxyl group at the terminal.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a low molecular weight polyester compound having alkoxylcarbonyl groups at both ends and a method for producing the same.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have completed the present invention. That is, according to the present invention, an aliphatic tetraester compound represented by the following general formula (1) is provided.

Embedded image (In the formula, R ¹ represents an alkyl group and R ² represents a divalent aliphatic group.) According to the invention, the following general formula (1)

Embedded image (Wherein R ¹ represents an alkyl group and R ² represents a divalent aliphatic group), in the method for producing an aliphatic tetraester compound, the following general formula (2) CH ₂ ═CHCOOR ¹ (2) ( In the formula, R ¹ represents an alkyl group, and an acrylic acid alkyl ester represented by the following general formula (3) HO—R ² —OH (3) (in the formula, R ² represents a divalent aliphatic group). The above method is provided, which comprises reacting an aliphatic diol represented by the formula with carbon monoxide in the presence of hydrogen and a catalyst consisting of a complex of cobalt carbonyl and a pyridine base.

The aliphatic tetraester compound of the present invention is
It is produced according to the following reaction formula. ^{_{2CH 2 = CHCOOR 1 + HO-}} R 2 -OH + 2CO → R 1 OCOC 2 H 4 COOR 2 OCOCH 2 COOR 1 (4)

Acrylic acid alkyl ester (CH₂= C
HCOOR¹) Alkyl group R in ¹Has 1 to 1 carbon atoms
8, preferably 1 to 3 alkyl groups. like this
Alkyl groups include methyl, ethyl and propyl
Group, butyl group, pentyl group, hexyl group, heptyl group,
An octyl group etc. are mentioned.

The divalent aliphatic group (aliphatic diol residue) R ² in the aliphatic diol (HO-R ¹ -OH) can be a chain or cyclic aliphatic group. The chain divalent aliphatic group is preferably an alkylene group having 2 to 8 carbon atoms such as ethylene, propylene, butylene, pentylene, hexylene and octylene. Cyclic divalent aliphatic groups include cyclobutylene, cyclopentylene, cyclohexylene,
It is preferably cycloalkylene or cycloalkylenedialkylene having 5 to 8 carbon atoms such as cyclohexylene dialkylene, cyclobutylene and cyclooctylene.

Specific examples of the aliphatic diol include ethylene glycol, 1,3-propanediol, 1,2-propanediol, 1,2-butanediol, 1,4-butanediol, 1,3-butanediol, 2,3-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 2,3-pentanediol, 2,4-
Pentanediol, 1,2-hexanediol, 1,3
-Hexanediol, 1,4-hexanediol, 1,
6-hexanediol, 1,5-hexanediol.
2,3-hexanediol, 2,4-hexanediol, 2,5-hexanediol, 3,4-hexanediol, 1,2-cyclohexanedimethanol, 1,3-
Examples thereof include cyclohexanedimethanol and 1,4-cyclohexanedimethanol.

The proportion of the aliphatic diol used is 0.4 to 0.5 mol, preferably 0.45 to 0.47 mol, per 1 mol of acrylic acid ester.

The reaction in the present invention is preferably carried out in the presence of a reaction solvent. Examples of the reaction solvent include aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene and cumene, ketone compounds such as acetone and methylethylketone, and alkoxyalkanes such as methoxymethane and dimethoxyethane. The amount of the reaction solvent used is 1 to 10 parts by weight, preferably 2 to 4 parts by weight, based on 1 part by weight of the acrylic ester.

The above reaction in the present invention is carried out in the presence of a catalyst comprising a complex of cobalt carbonyl and a pyridine base. Cobalt carbonyl may be added to the reaction system in the form of dicobalt octacarbonyl or cobalt hydrocarbonylpyridinium salt. As the pyridine base, various conventionally known pyridine bases can be used, and for example, pyridine, alkylpyridine, dialkylpyridine and the like can be used, and 3-alkylpyridine is particularly preferable. The number of carbon atoms of the alkyl group of 3-alkylpyridine is preferably 6 or less. The molar ratio of cobalt carbonyl to pyridine base in the catalyst system is 2 to 10 molecules of pyridine base per cobalt atom,
The number of molecules is preferably 2.5 to 6 molecules, and the catalytic ability is lowered when the amount of pyridine base is larger or smaller than this range. The amount of cobalt carbonyl added is 0.01 to 0.1 mol, preferably 0.025 to 0.075 mol as cobalt per mol of the starting material acrylate. The carbon monoxide used in the present invention contains hydrogen in an amount of 0.2 to 7.0% by volume, preferably 0.25 to 5.0% by volume, and more preferably 2.0 to 3.0% by volume. This hydrogen has a function of keeping the catalytic activity at a high level.

When carrying out the process of the present invention, the reaction temperature is 90 to 120 ° C., preferably 100 to 110 ° C., and the reaction pressure is the pressure of carbon monoxide, 20 to 10 ° C.
The pressure is 0 atm, preferably 25 to 50 atm. The reaction time is 20 to 200 minutes, preferably 60 to 150 minutes.

The catalyst contained in the reaction liquid obtained by the reaction of the present invention can be separated and recovered as a catalyst liquid by reducing the solubility of the reaction liquid in the catalyst. The catalyst liquid thus recovered can be reused.

The solubility of the catalyst in the reaction solution can be lowered by adding an organic solvent acting as a poor solvent for the catalyst, for example, an aliphatic hydrocarbon, to the reaction solution. Examples of the poor solvent include pentane, hexane, heptane, octane, nonane, decane, cyclohexane and methylcyclohexane. This poor solvent can be added in advance to the reaction solvent in an appropriate amount.

The poor solvent can be added in the form of a mixture with a good catalyst, for example, an aromatic hydrocarbon.
When the poor solvent is added in the form of a mixture with the good solvent, the proportion of the poor solvent in the mixture is at least 50% by weight or more, preferably 60 to 90% by weight. The amount of the poor solvent or the mixture of the poor solvent and the good solvent may be an amount sufficient for the catalyst in the reaction liquid to undergo phase separation (separation separation) as the catalyst liquid, and the preferable addition amount is a simple preliminary experiment. Can be easily obtained.

The catalyst liquid which has been phase-separated by adding a poor solvent to the reaction liquid and has precipitated is separated and recovered from the reaction liquid forming the upper layer due to the difference in specific gravity. The catalyst liquid thus separated and recovered has good catalytic activity and can be repeatedly used. Further, the reaction liquid after separating the catalyst liquid is
Aliphatic tetraester compound that is the target product and unreacted raw materials (acrylic acid ester and / or aliphatic diol)
And by-products, and a reaction solvent, which can be separated into each component by subjecting this to a distillation treatment. Further, prior to this distillation treatment, by adding and mixing an aqueous sulfuric acid solution to the reaction solution, the cobalt and pyridine bases contained in the reaction solution can be extracted and removed into the aqueous sulfuric acid solution. This sulfuric acid aqueous solution can be settled and separated by standing.

[0017]

Next, the present invention will be described in more detail with reference to examples.

Example 1 (1) First reaction experiment Methyl acrylate 9.04 g, 2,3-butanediol 4.50 g, cobalt carbonyl 0.85 g, 3-methylpyridine 15 mmol, toluene 15 g and acetone 2. 5g was put into a 300ml high pressure reactor and hydrogen 2.5
After introducing carbon monoxide containing vol% to 50 atm, the temperature was maintained at 110 ° C. and the reaction was carried out for 1 hour. After the reaction, the reactor was cooled to room temperature and then depressurized to normal pressure, nitrogen gas was introduced into the reactor, and 20 g of toluene and 40 g of n-hexane were added in a nitrogen gas stream. As a result, the reaction liquid was separated into two layers, and about 90 g of a supernatant liquid and about 10 g of a lower layer liquid were obtained. (2) Second reaction experiment Methyl acrylate 9.04 g, 2,3-butanediol 4.50 g, 3-methylpyridine 0.72 g, toluene 15 g and acetone 2.5 g were put in a 300 ml high-pressure reactor, Further, the lower layer liquid obtained in the first reaction was added, carbon monoxide containing 2.5 vol% of hydrogen was introduced until the pressure became 50 atm, and the reaction was kept at 110 ° C. for 3.5 hours. After the reaction, the reactor was cooled to room temperature and then depressurized to normal pressure,
Nitrogen gas was introduced into the reactor, and 20 g of toluene and 40 g of n-hexane were added in a nitrogen gas stream. as a result,
The reaction solution was separated into two layers, about 93 g of the supernatant and about 14 of the lower layer.
g was obtained.

Next, the first reaction experiment and the second reaction experiment
Add 3 ml of 3N dilute sulfuric acid to each supernatant obtained in the eye reaction experiment.
After stirring well, let stand and separate into two layers
Add a small amount of sulfuric acid mixed with sodium carbonate to the
After mixing, reduce the pressure to 1 mmHg and steam at 160-165 ° C.
Then, the compound A represented by the following structural formula (2,3-butane
Succinic acid methyl ester of diol) was obtained. This compound
The amount of substance A was 10.8 g in the first reaction experiment and
In the second reaction experiment, it was 13.5 g. (Compound) This compound A has a boiling point: 160 ° C./1 mmHg
It is an oily liquid at room temperature and its structure is proton NMR scan.
Confirmed by vector.

Example 2 (1) First Reaction Experiment Methyl acrylate 0.1 mol, 1,2-propanediol 0.05 mol, cobalt carbonyl 0.85 g,
15 mmol of 3-ethylpyridine, 15 g of toluene and 2.5 g of acetone were placed in a 300 ml high-pressure reactor, carbon monoxide containing 2.5 vol% of hydrogen was introduced until the pressure became 50 atm, and the temperature was kept at 110 ° C. for 1.5 hours. It was made to react.
After the reaction, the reactor was cooled to room temperature and then depressurized to normal pressure, nitrogen gas was introduced into the reactor, and toluene 20 was added in a nitrogen gas stream.
g and 40 g of n-hexane were added. As a result, the reaction liquid was separated into two layers, and about 87 g of a supernatant liquid and about 12 g of a lower layer liquid were obtained. (2) Second reaction experiment Methyl acrylate 0.1 mol, 1,2-propanediol 0.05 mol, 3-ethylpyridine deficiency supplement,
15 g of toluene and 2.5 g of acetone were placed in a 300 ml high-pressure reactor, the lower layer solution obtained in the first reaction experiment was added, and carbon monoxide containing 2.5 vol% of hydrogen was introduced until the pressure became 50 atm. After that, keep at 110 ℃ 2.5
Allowed to react for hours. After the reaction, the reactor was cooled to room temperature and then depressurized to normal pressure, nitrogen gas was introduced into the reactor, and 20 g of toluene and 40 g of n-hexane were added in a nitrogen gas stream.
As a result, the reaction liquid was separated into two layers, and about 93 g of a supernatant liquid and about 17 g of a lower layer liquid were obtained. (3) Third to fifth reaction experiments As in the second reaction experiment, the lower layer solution obtained in the previous reaction experiment was used to repeat the reaction experiment, and the supernatants obtained in these experiments were repeated. As in Example 1, 3 ml of 3N dilute sulfuric acid was added to each liquid and stirred well, the supernatant was neutralized and distilled under reduced pressure to obtain a compound B (succinic acid of 1,2-propanediol represented by the following structural formula. Methyl ester) was obtained. Table 1 shows the results obtained by repeating the reaction experiment 5 times.

[0021]

[Table 1] * Indicates the yield based on 1,2-propanediol

(Compound B) This compound B has a boiling point of 155 ° C./1 mmHg
It is an oily liquid at room temperature and its structure is proton NMR scan.
Confirmed by vector.

Example 3 (1) First reaction experiment Methyl acrylate 0.11 mol, 1,3-butanedio
0.05 mol, cobalt carbonyl 5 mmol,
3-methylpyridine 15 mmol, toluene 15 g,
2.5 g of seton was put into the high pressure reactor and 2.5 vol of hydrogen
% Carbon monoxide was introduced and maintained at 110 ° C and 50 atm.
The reaction was carried out for 1 hour. After the reaction, cool and depressurize at room temperature and atmospheric pressure.
Then, in a nitrogen stream, 20 g of toluene, n-hexane
40 g was added, and the mixture was well stirred and allowed to stand to separate into two layers.
Compound C (1,3-butanediol amber
Acid methyl ester) was obtained. Second layer liquid
It was used for the reaction experiment of. (2) Second reaction experiment Methyl acrylate 0.11 mol, 1,3-butanedio
0.05 mol, 3-methylpyridine 0.75 g,
The first reaction was added to 15 g of toluene and 2.5 g of acetone.
The lower layer liquid obtained from the test was added and placed in a high-pressure reactor, and hydrogen 2.
Introducing carbon monoxide containing 5 vol%, 110 ℃, 50
The reaction was carried out for 2 hours while maintaining the atmospheric pressure. After the reaction, cooling and depressurizing,
After normal temperature and pressure, toluene 20g, n in nitrogen stream
-Add 40 g of hexane, stir well and let stand, divide into 2 layers.
Let it go. Compound C (1,3-butanedio) from the supernatant
11.5 g of succinic acid methyl ester (1). (Compound C) The structural formula of the compound C is as follows. This compound C has a boiling point: 160 ° C./1 mmHg
It is an oily liquid at room temperature and its structure is proton NMR scan.
Confirmed by vector.

Example 4 (1) First reaction experiment Methyl acrylate 0.105 mol, 1,4-butanediol 0.05 mol, cobalt carbonyl 5 mmo
1, 3-methylpyridine 15 mmol, toluene 10 g
20g of mixed solvent of 10g and hexane was put in a high pressure reactor, carbon monoxide containing 2.5vol% of hydrogen was introduced, and 1
It was kept at 10 ° C. and 50 atm for reaction for 20 minutes. After the reaction,
After cooling, depressurizing, and returning to room temperature and atmospheric pressure, 20 g of toluene and 40 g of n-hexane were added in a nitrogen stream, well stirred, and allowed to stand to separate into two layers. The supernatant was taken out from the reaction container and stored. (2) Second reaction experiment A reactor containing the lower layer solution obtained in the first reaction experiment was charged with 0.105 mol of methyl acrylate, 0.05 mol of 1,4-butanediol, 10 g of toluene and 10 g of hexane. 20 g of the mixed solvent was added, carbon monoxide containing 2.5 vol% of hydrogen was introduced, and the reaction was carried out at 110 ° C. and 50 atmospheric pressure for 75 minutes. After the reaction, the mixture was cooled and depressurized to room temperature and atmospheric pressure, and then 20 g of toluene and 40 g of n-hexane in a nitrogen stream.
60 g of a mixed solvent of and was added and well stirred, and the mixture was allowed to stand and separated into two layers. The supernatant was taken out from the reaction vessel and mixed with the first supernatant, 5 ml of 3N sulfuric acid was added and mixed well, neutralized with sodium carbonate, and the pressure was reduced to 1 mmHg,
Distillation at 0 ° C. gave 18.4 g of compound D (succinic acid methyl ester of 1,4-butanediol). (Compound D) The structural formula of the compound D is as follows. _{CH 3 OCOC 2 H 4 COOCH 2} -CH 2 -CH 2 -CH 2 -OCOC 2 H 4 COOCH 3 (8) The compound D is an oily liquid at room temperature having a boiling point 190 ° C. / 1 mmHg, the The structure was confirmed by the proton NMR spectrum.

Example 5 Methyl acrylate 0.2 mol, ethylene glycol 0.1 mol, cobalt carbonyl 2 mmol, 3-butylpyridine 6 mmol, benzene 20 g and 1,2-
20 g of dimethoxyethane was placed in the same high-pressure reactor as in Example 1, carbon monoxide containing 2.5 vol% of hydrogen was added, and the mixture was reacted at 110 ° C. and 50 atm for 7 hours. The reaction was carried out for 1 hour. After the reaction was completed, the temperature was brought to room temperature and normal pressure, and the mixture was transferred to a separatory funnel and 50 g of toluene was added.
Hexane (60 g) was added and the mixture was stirred well, 3N sulfuric acid (3 ml) was added to the supernatant, the mixture was stirred, neutralized with sodium carbonate, and the product was separated by vacuum distillation. As a result, compound E
1 (succinic acid methyl ester of ethylene glycol)
Obtained 1.4 g. The yield of this product based on ethylene glycol was 39.3%. (Compound E) The structural formula of the compound E is as follows. _{CH 3 OCOC 2 H 4 COOCH 2} -CH 2 -OCOC 2 H 4 COOCH 3 (9) The compound E is a liquid oily at room temperature with 160 ° C. / 1 mmHg, the structure confirmed by proton NMR spectrum Was done.

Example 6 Methyl acrylate 0.055 mol, cyclohexane-
1,4-diol 0.025 mol, cobalt carbonyl 4 mmol, 3-methylpyridine 12 mmol, 1,
40 g of 2-dimethoxyethane was placed in the same high-pressure reactor as in Example 1, carbon monoxide containing 2.5 vol% hydrogen was added, and the mixture was reacted at 110 ° C. and 50 atm for 1 hour. Adjust to pressure, transfer to separatory funnel, 65 g of hexane
Was added and stirred, 3N sulfuric acid (3 ml) was added to the supernatant, and the mixture was sufficiently stirred and then neutralized with an aqueous sodium carbonate solution.
Next, the same experiment was performed again, and the product solutions obtained in the two experiments were combined and the products were separated by vacuum distillation. as a result,
4.3 g of compound F (methyl succinic acid ester of cyclohexane-1,4-diol) was obtained. The yield of this product based on cyclohexane-1,4-diol is 25%.
Met. (Compound F) The structural formula of the compound F is as follows.

Embedded image This compound F was an oily liquid at normal temperature having a boiling point of 230 ° C./1 mmHg, and its structure was confirmed by the proton NMR spectrum.

[0027]

EFFECT OF THE INVENTION The aliphatic tetraester compound of the present invention has a structure having carboxyl groups esterified with alkyl groups at both ends, and can be transesterified with alcohol. Therefore, this compound can be converted into a high molecular weight polyester by transesterification with glycol. The compound of the present invention has biodegradability due to its aliphatic ester bond and can be used as a biodegradable lubricant, a biodegradable polymer additive, or the like. The method of the present invention is an excellent industrial method for producing the above-mentioned aliphatic tetraester compound in good yield.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ikuo Takahashi 2-8-11 Nishi-Shimbashi, Minato-ku, Tokyo 7th Toyo Kaijuku Building 8th floor CO2 fixation project room (72) ) Inventor Takashi Masuda 1-1-1, Higashi, Tsukuba-shi, Ibaraki Institute of Industrial Science and Technology (72) Inventor Kenji Kawamoto 2-8-11 Nishishinbashi, Minato-ku, Tokyo 7th Toyo Kaiji Building 8F Foundation Research Institute for Global Environment and Industrial Technology CO2 fixation etc. project room

Claims (3)

[Claims] 1. An aliphatic tetraester compound represented by the following general formula (1). Embedded image (In the formula, R ¹ represents an alkyl group and R ² represents a divalent aliphatic group) 2. The following general formula (1): (Wherein R ¹ represents an alkyl group and R ² represents a divalent aliphatic group), in the method for producing an aliphatic tetraester compound, the following general formula (2) CH ₂ ═CHCOOR ¹ (2) ( In the formula, R ¹ represents an alkyl group, and an acrylic acid alkyl ester represented by the following general formula (3) HO—R ² —OH (3) (in the formula, R ² represents a divalent aliphatic group). Wherein the aliphatic diol represented by and carbon monoxide are reacted in the presence of a catalyst consisting of a complex of cobalt carbonyl and a pyridine base and hydrogen. 3. The reaction solution obtained by the method according to claim 1 is added with an organic solvent which acts as a poor solvent for the catalyst to precipitate and separate the catalyst solution, and the precipitated and separated catalyst solution is used. The method of claim 2, wherein the reaction is performed.