JPH0543511A - Production of alkyldicarboxylic acid diaryl ester - Google Patents

Abstract

PURPOSE:To obtain an alkyldicarboxylic acid diaryl ester useful as a raw material for polyester, a sensitizer for heat-sensitive recording paper, etc., in high purity and yield at a low cost in an easily purifiable state without causing discoloration of the reaction system. CONSTITUTION:The objective alkyldicarboxylic acid diaryl ester difficult to be purified by distillation is produced at a low cost by carrying out the dehydrative esterification reaction of (A) a compound of formula (R is 1-8C straight or branched hydrocarbon group) with (B) a monohydric phenol, preferably a phenol which may have substituent (alkyl, alkenyl, aryl, cycloalkyl, alkoxy, etc.) in the presence of an acid catalyst consisting of boric acid or a mixture of (a) boric acid and (b) one or more acids selected from sulfuric acid, hypophosphorous acid, methanesulfonic acid, benzenesulfonic acid, sulfonic acid-type ion-exchange resin, p-toluenesulfonic acid, polyphosphoric acid and hydrochloric acid, preferably a combination of boric acid, sulfuric acid and, as necessary, hypophosphorous acid.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a process for producing an alkyldicarboxylic acid diaryl ester.

[0002]

2. Description of the Related Art As a method for producing an alkyldicarboxylic acid diaryl ester in the presence of an acid catalyst, there is a method in which an alkyldicarboxylic acid and phenol are dehydrated and esterified in the presence of sulfuric acid, p-toluenesulfonic acid or polyphosphoric acid. Known (eg, New Experimental Chemistry Course, Volume 14 (2), P10
04, Maruzen).

[0003]

However, in the conventional method, a long reaction time is required, a yield is low because a side reaction product is formed, and the reaction product is remarkably colored.
Moreover, since the alkyldicarboxylic acid diaryl ester has a high boiling point, it is difficult to purify it by distillation, so that it was not possible to economically obtain a highly pure alkyldicarboxylic acid diaryl ester in a high yield.

[0004]

Means for Solving the Problems As a result of intensive studies to solve these problems, the present inventors have found that by using an acid catalyst composed of boric acid, an alkyldicarboxylic acid diaryl ester can be economically produced with high purity and high yield. The present invention has been achieved by finding that it can be manufactured at a high rate. That is, the present invention provides an alkyldicarboxylic acid (A) represented by the general formula HOOC-R-COOH (wherein R represents a linear or branched hydrocarbon group having 1 to 8 carbon atoms) and a monohydric phenol ( In the method for producing an alkyldicarboxylic acid diaryl ester, which comprises subjecting B) to dehydration esterification in the presence of an acid catalyst (C), (C) is boric acid alone or boric acid and sulfuric acid, hypophosphorous acid, methanesulfonic acid, benzenesulfone. A process for producing an alkyldicarboxylic acid diaryl ester, which is characterized in that it is used in combination with at least one other acid selected from the group consisting of an acid, a sulfone type ion exchange resin, p-toluenesulfonic acid, polyphosphoric acid and hydrochloric acid.

Specific examples of the alkyldicarboxylic acid (A) in the present invention include linear alkyldicarboxylic acids such as malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid and sebacic acid, and methyl. Malonic acid, ethyl malonic acid, methyl succinic acid, dimethyl succinic acid, α-methyl glutaric acid, dimethyl glutaric acid,
Examples thereof include branched alkyldicarboxylic acids such as α-methyladipic acid. Of these, preferred are malonic acid, succinic acid, glutaric acid and adipic acid, and more preferred is adipic acid.

In the present invention, specific examples of the monohydric phenol (B) include phenol; naphthol; alkyl groups (methyl, ethyl, n-propyl, t-butyl, hexyl,
Octyl, nonyl, decyl group, etc.), alkenyl group (isopropenyl, allyl group, etc.), aryl group (phenyl, tolyl, xylyl, biphenyl, naphthyl, cumyl group, etc.), cycloalkyl group (cyclohexyl group, etc.), alkoxy group ( Methoxy group, ethoxy group, etc.), aryloxy group (phenoxy group, etc.), alkylthio group (methylthio group, ethylthio group, etc.), arylthio group (phenylthio group, etc.), halogen group (fluoro, chloro, bromo group, etc.), cyano group or Substituted phenol substituted with a nitro group; substituted naphthol substituted with a similar group, and the like. Preferred of these are phenols and substituted phenols, especially phenols and cresols.

In the present invention, the acid catalyst (C) is boric acid alone or boric acid and sulfuric acid, hypophosphorous acid, methanesulfonic acid,
Benzenesulfonic acid, sulfonic acid type ion exchange resin, p-
It is used in combination with at least one other acid selected from the group consisting of toluenesulfonic acid, polyphosphoric acid and hydrochloric acid. Of these, preferred is the combined use of boric acid, sulfuric acid and, if necessary, hypophosphorous acid.

When (C) is a combination of boric acid, sulfuric acid and optionally hypophosphorous acid, the weight ratio of boric acid: sulfuric acid: hypophosphorous acid is usually 1: (0.05-10) :( 0-10). is there. More preferably, it is 1: (0.1-1) :( 0.5-2). If the ratio of sulfuric acid or hypophosphorous acid exceeds 10, the reaction takes a long time and the reaction mixture becomes markedly colored, which makes purification difficult.

In the production method of the present invention, the dehydration esterification reaction may be carried out without solvent or in a solvent.

When the reaction is carried out without a solvent, it is preferable to use an excessive amount of (B) based on the equivalent ratio of (A) and (B) in order to effectively carry out the dehydration esterification reaction.

When carried out in a solvent, the boiling point of the organic solvent used is usually 40 to 220 ° C. Specific examples of the organic solvent include aromatic hydrocarbon solvents (benzene, xylene, ethylbenzene, toluene, etc.), aliphatic hydrocarbon solvents (hexane, pentane, etc.), halogenated hydrocarbon solvents (chloroform, ethylene dichloride, etc.). Etc.), ether solvents (tetrahydrofuran, dioxane, etc.) and the like. You may use together 2 or more types of these. Among these, preferred is one or more selected from benzene, toluene, xylene and ethylbenzene.

(A) :( B): used in the method of the present invention.
The weight ratio of (C) is usually 100: (50 to 5000): (0.1 to 1)
0). If (C) is less than 0.1, the reaction takes a long time and the yield is low, and if it exceeds 10, it is uneconomical. (B)
When it is less than 50, the monoaryl ester of (A) is mainly produced, and when it exceeds 5,000, excess (B) must be removed during purification, which is troublesome and uneconomical.

When an organic solvent is used in the dehydration esterification reaction, the amount used is usually 5000 parts by weight or less based on 100 parts by weight of (A).

As a method for removing water by-produced by the dehydration esterification reaction during the reaction, a method of continuously removing it with a dehydrator or the like, and a dehydrating agent (for example, dicyclohexylcarbodiimide, trifluoroacetic anhydride, etc.) are present together. The method of making it include. Examples of the dehydrating device include a Dean-Stark type dehydrating device, a device in which a desiccant [Molecular Sieve (Molecular Sieve 5A, etc.), magnesium sulfate, etc.] is placed in a Soxhlet extractor.

An example of a method for purifying and isolating an alkyldicarboxylic acid diaryl ester from the product after completion of the dehydration esterification reaction is to wash the product with weak alkaline water to remove the acid catalyst (C) and unreacted components and After removing the by-product, the alkyldicarboxylic acid diaryl ester can be isolated by removing the solvent when a solvent is used. If necessary, it may be purified by recrystallization using various solvents.

[0016]

The present invention will be further described below with reference to examples, but the present invention is not limited thereto.

Example 1 In a 500 ml four-necked flask equipped with a Dean-Stark type dehydrator, 229 g of xylene, 51 g of adipic acid and 99 of phenol
g, 1.1 g of boric acid, 0.3 g of sulfuric acid and 1.0 g of hypophosphorous acid were added and the temperature of the xylene reflux was raised to 144 ° C. After removing 12 g of produced water under reflux for about 8 hours, the reaction mixture, which was almost transparent, was cooled to 50 ° C. The mixture was washed with an aqueous solution of sodium hydroxide and then with water to remove unreacted substances and catalyst residues.
Further, 150 g of xylene was removed under reduced pressure and cooled with ice. The mixture was filtered off to obtain 91 g of white crystalline adipic acid diphenyl ester (yield 88%, melting point 107-108 ° C).

Example 2 In a 500 ml four-necked flask equipped with a Dean-Stark type dehydrator, 229 g of xylene, 51 g of adipic acid and 9 phenols were added.
9 g, 1.1 g boric acid, 0.3 g sulfuric acid were added, and the reflux temperature of xylene
The temperature was raised to 144 ° C. Generated water 1 while refluxing for about 12 hours
After removing 2g, the reaction mixture that turned slightly brown was heated to 50 ° C.
Cooled down. The mixture was washed with an aqueous solution of sodium hydroxide and then washed with water to remove unreacted substances and catalyst residues to obtain an almost transparent solution. Further, 150 g of xylene was removed under reduced pressure and cooled with ice. The mixture was filtered off to obtain 80 g of adipic acid diphenyl ester (yield 77%, melting point 107-108 ° C).

Example 3 To a 500 ml four-necked flask equipped with a Dean-Stark type dehydrator, 229 g of xylene, 51 g of adipic acid, 120 g of p-cresol, 1.1 g of boric acid, 0.3 g of sulfuric acid and 1.0 g of hypophosphorous acid were added and xylene was added. The reflux temperature was raised to 144 ° C. After removing 12 g of produced water under reflux for about 10 hours, the reaction mixture, which was almost transparent, was cooled to 50 ° C. The mixture was washed with an aqueous solution of sodium hydroxide and then with water to remove unreacted substances and catalyst residues. Further, 150 g of xylene was removed under reduced pressure and cooled with ice. The mixture was filtered off to obtain 95 g (yield 84%) of adipic acid dicresyl ester as white crystals.

Comparative Example 1 The reaction was carried out in the same manner as in Example 1 except that boric acid and hypophosphorous acid were not used. 5 g of produced water even after 24 hours of reaction time
And the reaction system was black. The mixture was washed with an aqueous sodium hydroxide solution and then with water. Further, xylene was removed under reduced pressure and cooled with ice. The mixture was filtered off, but 30 g of a black product containing adipic acid diphenyl ester as the main component (yield 2
9%, melting point 100-108 ° C) was obtained. Furthermore, this black product was recrystallized using 200 g of ethanol, but could not be decolorized.

[0021]

INDUSTRIAL APPLICABILITY The production method of the present invention is economical in that the yield is good, the reaction product system is not colored, and the purification by distillation is difficult because the diaryl ester of alkyldicarboxylic acid is highly purified. It is a manufacturing method. The obtained alkyldicarboxylic acid diaryl ester is useful not only as a raw material for polyester, but also as a sensitizer for thermal recording paper and other various synthetic intermediates.

Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location B01J 31/02 103 31/08 C07C 67/08 8018-4H // C07B 61/00 300 (72) Inventor Fujiwara Risa 1-11, Hitotsubashi-honcho, Higashiyama-ku, Kyoto Sanyo Chemical Industry Co., Ltd.

Claims (3)

[Claims] 1. An alkyldicarboxylic acid (A) represented by the general formula HOOC-R-COOH (wherein R represents a linear or branched hydrocarbon group having 1 to 8 carbon atoms) and a monohydric phenol ( In the method for producing an alkyldicarboxylic acid diaryl ester, which comprises subjecting B) to dehydration esterification in the presence of an acid catalyst (C), (C) is boric acid alone or boric acid and sulfuric acid, hypophosphorous acid, methanesulfonic acid, benzenesulfone. A process for producing an alkyldicarboxylic acid diaryl ester, which is used in combination with at least one other acid selected from the group consisting of an acid, a sulfone type ion exchange resin, p-toluenesulfonic acid, polyphosphoric acid and hydrochloric acid. 2. The monohydric phenol (B) is phenol, or an alkyl group, an alkenyl group, an aryl group, a cycloalkyl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, a halogen group, a cyano group or a nitro group. The method according to claim 1, which is a substituted phenol substituted with a group. 3. The method according to claim 1 or 2, wherein the acid catalyst (C) is a combination of boric acid, sulfuric acid and, if necessary, hypophosphorous acid.