DE1231688B - Process for the preparation of isocyanatocarboxylic acid esters of polyfunctional hydroxy compounds - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

C 07c

German KL: 12 ο-22

Number: 1231 688

File number: F 45839IV b / 12 ο

Filing date: April 17, 1965

Opened on: January 5, 1967

The invention relates to a method of manufacture of isocyanatocarboxylic acid esters of polyfunctional hydroxy compounds, d. H. of connections, which contain at least two ester and isocyanate groups in the same molecule.

The preparation of aliphatic and aromatic monoisocyanates containing ester groups is known. Are described z. B. the esters of / j-isocyanatoacetic acid and the m-substituted isocyanatobenzoic acid esters. It is also known that polyisocyanates containing aromatic ester groups can be prepared by reacting the esters of polyhydric esters Alcohols with aromatic carboxylic acids in the aromatic nucleus of the carboxylic acid residue at least contain two primary amino groups, with phosgene (German Patent 1,078,115). Be complementary Described polyisocyanates containing ester groups, mono- or polyvalent benzoic acid esters Phenols, which have aromatically bound amino groups in both nuclei, were produced (German patent specification 1 085 869). This procedure is more aliphatic for the corresponding esters Aminocarboxylic acids cannot be used because, on the one hand, the production of such esters is difficult and on the other hand, their reaction with phosgene does not lead to the desired compounds.

It has now been found that esters of aliphatic isocyanatocarboxylic acids with polybasic Alcohols or phenols are obtained when aliphatic isocyanatocarboxylic acid chlorides are mixed with polyvalent ones Reacts alcohols or phenols in the presence of agents that bind hydrogen chloride.

The feasibility of this method is surprising because it is to be expected that not only the Acid chloride group but also the isocyanate group easily reacts with hydroxyl groups. Amazingly what remains in the process of the invention is the reaction, which is known to be easy from hydroxyl group and isocyanate group to urethane.

The following are suitable as polyfunctional hydroxy compounds for the process according to the invention:

Aromatic polyhydroxy compounds, especially polyhydric phenols, such as resorcinol, hydroquinone, 4,4'-dihydroxydiphenyl, 4,4'-dihydroxydiphenylmethane, 2,2- (4,4'-dihydroxydiphenyl) propane, 1,1- ( 4,4'-dihydroxy-diphenyl) -cyclohexane, phloroglucinol and 4-hydroxya, a'-bis- (p-hydroxyphenyl) -a, a, a ', a'-tetramethylm-xylene; aliphatic polyhydroxy compounds, especially polyhydric aliphatic alcohols, such as processes for the preparation of
Isocyanatocarboxylic acid esters are more polyfunctional
Hydroxy compounds

Applicant:

Paint factories Bayer Aktiengesellschaft,

Leverkusen

Named as inventor:

Dr. Heinrich Krimm, Krefeld-Bockum;

Dr. Georg Malamet, Krefeld;

Dr. Hermann Schnell, Krefeld-Uerdingen

Ethylene glycol, propanediol- (1,3), 2-chloro-propanediol- (l, 3), Butanediol- (1,4), hexanediol- (1,6), hexanediol- (2,5), 2,5-dimethylhexanediol- (2,5), Heptanediol- (1,7), octanediol- (1,8), glycerin and trimethylolpropane;

cycloaliphatic polyhydroxy compounds such as cyclohexanediol - (1,4), 2,2 - (4,4 '- dihydroxydicyclohexyl) propane and 4,4'-dihydroxydicyclohexyl methane.

As aliphatic isocyanatocarboxylic acid chlorides are in particular the chlorides of alkyl and Cycloalkylcarboxylic acids which are substituted by isocyanate groups are suitable. These connections can also contain other substituents which are inert towards the reaction. Examples of such compounds are: 3-isocyanatoalanine chloride, 4-isocyanatobutyric acid chloride, 5 - isocyanatovaleric acid chloride, 6-isocyanatocaproic acid chloride, 9-isocyanatopelargonic acid chloride, 11-isocyanatoundecanoic acid chloride and 4-isocyanatocyclohexanecarboxylic acid chloride.

As hydrogen chloride binding agents, for. B. are used: alkali and alkaline earth metal hydroxides such as sodium hydroxide, potassium hydroxide, calcium hydroxide, barium hydroxide and tertiary amines such as triethylamine, tributylamine, N, N-dimethylaniline, pyridine and quinoline.

As solvents are, for. B. suitable: Aliphatic ethers and chlorinated hydrocarbons such as diethyl ether, Methylene chloride, chloroform, carbon tetrachloride, dichloroethane, chlorobenzene and Dichlorobenzenes.

The process of the invention can be carried out in a number of ways.

609 750/428

You can ζ. B. the implementation in a two-phase system of aqueous liquor and one of the Carry out said solvent by dissolving the hydroxy compound in the aqueous alkali or suspended and the inert solvent is added. Subsequently, if necessary, it is released Addition of triethylamine as a catalyst, the isocyanatocarboxylic acid chloride add dropwise to the above suspension at reaction temperature.

The reaction can also be carried out in a homogeneous phase by adding the hydroxy compound dissolved or suspended in one of the solvents mentioned and at least the stoichiometric Amount of the tertiary amine and the isocyanatocarboxylic acid chloride at the same time at the reaction temperature lets drip.

You can also use the alkali or alkaline earth metal salt of the hydroxy compound to be reacted in Suspend one of the solvents mentioned and leave, optionally after adding triethylamine as a catalyst, the isocyanatocarboxylic acid chloride is added dropwise at the reaction temperature.

The hydroxy compound and the isocyanatocarboxylic acid chloride are expediently in accurate stoichiometric ratio used, that is, 1 mole of isocyanatocarboxylic acid chloride per hydroxyl group to be converted.

At least the stoichiometric amount of hydrogen chloride binding agent is required however, any excess can be used in most cases.

The reaction temperatures are generally between -20 and +20 ³ C, preferably between -5 and -5 C.

The working up of the reaction mixtures is expediently carried out in such a way that first the Solutions of the products freed from salts. This can either be done by shaking out the solutions with ice water or, if the salts have precipitated in crystalline form in the course of the reaction, with suction and then shaken out with ice water.

The products obtained after the solvent has been distilled off can then possibly contain excess tertiary amine by distillation or by shaking with ice-cold, dilute hydrochloric acid removed.

In this way, the isocyanatocarboxylic acid esters of the polyfunctional ones are obtained in good yields Hydroxy compounds in pure form as colorless to pale yellow, highly viscous syrups, which in some Cases solidify in crystalline form.

The compounds can be used to manufacture plastics.

example 1

22.8 g of 2,2- (4,4'-dihydroxydiphenyl) propane (0.1 mol) are dissolved in 110 ml of 2η sodium hydroxide solution. After addition of 150 ml of methylene chloride and 3 drops of triethylamine the well-stirred suspension is cooled to 0 ⁰ C. Then 35.2 g of 6-isocyanatocaproic acid chloride (0.2 mol) are added dropwise at OC in the course of 30 minutes.

After 45 minutes of stirring at 0 ^: C, the methylene chloride phase is separated off and washed three times with 50 ml of ice water each time. After drying over sodium sulfate, the methylene chloride is distilled off. The residual product is heated at 0.5 Torr to 15O ⁰ C, the triethylamine and unreacted isocyanatocarboxylic distill.

43 g of 4,4'-bis- (6-isocyanatocaproyloxy) -diphenylpropane- (2.2) (86% of theory) are obtained as a pale yellow, highly viscous liquid with a boiling point of 303 to 305 ⁰ C / 1.1 to 1, 3 torr.

OCN - (CHo) ₅ COO

OCO - (CHo) ₅ - NCO

C ₂₉ H ₃₄ N ₂ O ₆ (506.6):

Calculated NCO 16.6%;

found NCO 16.0%.

Example 2

In a solution of 22.8 g of 2,2- (4,4'-dihydroxydiphenyl) propane (0.1 mol) in 110 ml of 2N sodium hydroxide solution 150 ml of methylene chloride are suspended.

OCN - (CH ₂ ) ioCOO

C ₃₉ Hj ₄ N ₂ O ₆ (636.8):

Calculated NCO 13.2%;

found NCO 12.9%.

Example 3

To a solution of 36.2 g of 4-hydroxy - «, a'-bis- (p - hydroxyphenyl) - «, α,« ', «' - tetramethyl - m - xylene After adding 3 drops of triethylamine, 49.2 g of 11-isocyanatoundecanoic acid chloride are added to this suspension (0.2 mol) are added dropwise in 30 minutes at OC. After 45 minutes of stirring at 0 C, as described in Example 1, worked up.

61 g of 4,4'-bis- (II-isocyanatoundecoyloxy) -diphenylpropane- (2.2) are obtained (96% of theory) as a colorless, highly viscous syrup that solidifies the wax. F. 32 to 35 C.

OCO - (CH ₂ ) I ₀ - NCO

(0.1 mol) in 166 ml of 2 η sodium hydroxide solution are added to 400 ml of methylene chloride and 3 drops of triethylamine. 52.8 g of 6-isocyanatocaproic acid chloride are then added to the well-stirred suspension in the course of 30 minutes (0.3 mol) are added dropwise at OC.

After 45 minutes of stirring at 0 ^: C and working up as described in Example 1, 64 g of 4- (6-isocyanatocaproyloxy) -a, a'-bis- [p- (6-isocyanato-

5 6

caproyloxy) - phenyl] - α, α, α ', α'-tetramethyl - m - xylene (82% of theory) as a brownish, highly viscous syrup.

CH ₃
- / V-

CH3

/ CH3

OCO - (CHo) ₅ - NCO

Cj ₅ H ₅₃ N ₃ O ₉ (779.9):

Calculated NCO 16.1%;

found NCO 14.9%.

Example 4 Suspended in a solution of 11.8 g of hexanediol (1.6) methylene chloride and 3 drops of triethylamine.

After Zutropfenlassen of 35.2 g of 6-isocyanatocaproyl (0.2 mole) in 30 minutes at 0 ° C 65 minutes at O ⁰ C is stirred. After working up as described in Example 1, 29.7 g of 6-bis (6-isocyanatocaproyloxy) hexane (75% of theory) are obtained as a colorless, viscous oil from

(0.1 mol) in 110 ml of 2 η sodium hydroxide solution are 150 ml of 20 bp 225 ° C / 0.25 Torr.

OCN - (CHs) ₅ COO - (CHa) ₆ - OCO - (CHo) ₅ - NCO

C ₂₀ H ₃₂ N ₂ O ₆ (396.5):

Calculated NCO 21.2%;

found NCO 20.9%.

Example 5

35.2 g of 6 ^{are added at 0} ° C. to a suspension of 24 g of 2,2- (4,4'-dihydroxydicyclohexyl propane (0.1 mol) in 110 ml of 2N sodium hydroxide solution, 150 ml of methylene chloride and 3 drops of triethylamine -Isocyanatocapronsäurechlorid (0.2 mol) are added dropwise in 30 minutes. After 2 hours stirring at 0 ⁰ C is suctioned from the unreacted diol and the organic phase worked up as in example 1.

25.9 g of 4,4'-bis- (6-isocyanatocaproyloxy) -dicyclohexylpropane- (2.2) (50% of theory) are obtained as a yellow, highly viscous syrup with a boiling point of about 250 ^° C. / 0.5 Torr.

OCN- (CH ₂ ) ₅ - COO

C ₂₉ H ₄₆ N ₂ O ₆ (518.6):

Calculated NCO 16.2%;

found NCO 16.1%.

Example 6

11.8 g of hexanediol (1.6) (0.1 mol) are dissolved in 200 ml of methylene chloride. 28.4 g of quinoline (0.22 mol) and 35.2 g of 6-isocyanatocaproic acid chloride (0.2 mol) are added dropwise equivalent to this solution at 0 ^{° C. from two separate dropping funnels in 45 minutes.}

After stirring for 15 minutes at ⁰ ° C., the mixture is shaken out three times with 50 ml of ice water each time and worked up analogously to Example 1. 36 g of 6-bis- (6-isocyanatocaproyloxy) -hexane (91% of theory) are obtained.

Example 7

To a suspension of 27.2 g (0.1 mol) of the disodium salt of 2,2- (4,4'-dihydroxy-diphenyl) propane in 250 ml of dry ether is allowed after addition of 3 drops of triethylamine at 0 C ⁰ add dropwise SS ^ go-isocyanatocaproic acid chloride (0.2 mol) in 30 minutes.

After stirring for 60 minutes at 0 ^° C., the precipitated common salt is filtered off with suction. After distilling off the solvent, 38 g of 4,4'-bis- (6-iso-OCO- (CHo) ₅ -NCO are obtained

cyanatocaproyloxy) diphenylpropane (2.2) (75% of theory).

Example 8

To a suspension of 27.2 g (0.1 mol) of the disodium salt of 2,2- (4,4'-dihydroxy-diphenyl) propane in 200 ml of methylene chloride is allowed after addition of 3 drops of triethylamine at 0 ⁰ C in 35.2 g of 6-isocyanatocaproic acid chloride (0.2 mol) are added dropwise over 30 minutes.

After 75 minutes of stirring at 0 ^° C., the precipitated common salt is filtered off with suction. The filtrate is extracted twice with 50 ml of ice water each time and dried over sodium sulfate. After the solvent has been distilled off, 50 g of 4,4'-bis (6-isocyanatocaproyloxy) diphenyl propane (2.2) (98.5% of theory) are obtained.

Claims (1)

Claim: Process for the preparation of isocyanatocarboxylic acid esters polyfunctional hydroxy compounds, characterized in that aliphatic isocyanatocarboxylic acid chlorides are used with polyhydric alcohols or phenols in the presence of agents that bind hydrogen chloride implements.