KR101856566B1 - New preparation method of 4'-Hydroxy-4-biphenylcarboxylic acid - Google Patents

Abstract

[화학식 2]

상기 화학식 2에서,
R¹은 탄소수 1~6의 알킬, 시클로알킬, 또는 아릴기이고,
R은 수소 또는 알킬기이고,
X는 염소, 브롬, 요오드, 메탄설포네이트, 벤젠설포네이트, 톨루엔설포네이트에서 선택되는 이탈기이고,
4차 아민 염으로는 세 개의 서로 같거나 다른 알킬기나 방향족 탄화수소로 이루어지는 아민 염, 또는 피리딘과 같이 고리화된 방향족 아민 염이다.The present invention relates to a novel process for preparing 4'-hydroxy-4-biphenylcarboxylic acid represented by the following formula (1), which is characterized in that it is prepared by hydrolysis from a compound of the following formula (2)
[Chemical Formula 1]

(2)

In Formula 2,
R ¹ is an alkyl, cycloalkyl or aryl group having 1 to 6 carbon atoms,
R is hydrogen or an alkyl group,
X is a leaving group selected from chlorine, bromine, iodine, methane sulfonate, benzene sulfonate, toluene sulfonate,
Quaternary amine salts are amine salts consisting of three identical or different alkyl groups or aromatic hydrocarbons, or cyclized aromatic amine salts such as pyridine.

Description

4'-hydroxy-4-biphenylcarboxylic acid, a novel preparation method of 4'-hydroxy-4-biphenylcarboxylic acid,

The present invention relates to a novel process for preparing 4'-hydroxy-4-biphenylcarboxylic acid. More specifically, the present invention relates to a process for preparing 4'-hydroxy-4-biphenylcarboxylic acid which is useful as liquid crystal, liquid crystal polymer, Phenyl carboxylic acid from 4-phenylphenol.

Classifying existing techniques for 4'-hydroxy-4-biphenylcarboxylic acid useful as a liquid crystal, a liquid crystal polymer, and a high heat dissipation high heat-

Two differently substituted benzene derivatives are coupled by a Suzuki coupling reaction as shown in the following chemical reaction formula 1, A method for synthesizing 4'-hydroxy-4-biphenylcarboxylic acid is known from JP 2009298727, RCS Advances, 2014, 4 (6), 2984, Organic & Bimolecular Chemistry 2014, 12 (25)

[Chemical reaction formula 1]

However, such a Suzuki coupling reaction is industrially unrealistic because expensive boric acid compounds or expensive palladium catalysts must be used.

In contrast, methods for synthesizing 4'-hydroxy-4-biphenylcarboxylic acid through carboxylation and deprotection from a 4-phenylphenol derivative in which a hydroxy group is protected with a protecting group are known.

In Huaxue Shiji 2007, 29 (4), 239, a hydroxy group is protected with a benzyl group and carboxylated as in the following chemical reaction formula 2, and then the target compound 4'-hydroxy-4-biphenylcarboxyl A method of synthesizing an acid is known.

[Chemical reaction formula 2]

In this method, the hydroxy group of phenylphenol is protected with an acetyl group, acetylated, deacetylated, then protected again with a benzyl group, and then the hypochlorite is reacted under an alkaline condition to effect carboxylation. Then, the protecting group benzyl group is deprotected 4'-hydroxy-4-biphenylcarboxylic acid was synthesized in the same manner as in Synthesis Example 1.

This method consists not only of complicated multistage reactions such as multi-step protection-deprotection, but also to commercialization such as using a large amount of hypochlorite and requiring industrially dangerous hydrogen reaction for deprotection of the benzyl protecting group It is evaluated as a process that lacks economic efficiency.

Huaxue Shiji 2005, 13 (6), 614 discloses a method similar to [Reaction Scheme 2] As shown in the following chemical reaction formula 3, the hydroxyl group of phenylphenol is first protected with a methyl group, and then the hypochlorite is reacted under alkaline conditions to carry out carboxylation. Then, the protecting group is reacted with bromic acid in an acetic acid solvent Hydroxy-4-biphenylcarboxylic acid as a target compound by a process of deprotecting a methyl group.

[Chemical reaction formula 3]

However, this method also uses a large amount of hypochlorite for deprotection of the methyl protecting group, and it requires a high-temperature reaction using expensive acetic acid as a solvent. do.

Separately, in Japanese Patent No. 04243851, a method of protecting two 4-phenylphenol hydroxy groups by utilizing a phosgene derivative and carboxylating them using oxalyl chloride, thereby obtaining a target compound 4'-hydroxy-4 -Biphenylcarboxylic acid, and Japanese Patent No. 63119440, a phosgene derivative N, N-dimethyl chloroformamide is obtained as in the following [Chemical Reaction Scheme 4], and the resultant is reacted with 4-phenylphenol and hydrolyzed Methods for synthesizing the desired compound 4'-hydroxy-4-biphenylcarboxylic acid have been known.

[Chemical reaction formula 4]

However, these methods are considered to be economical in terms of refining due to impurities such as isomers, which are produced due to the use of a highly reactive raw material, and phosgene derivatives or expensive oxalyl chloride which are industrially difficult to handle .

In addition, International Patent Publication No. 2004/76397 discloses a method of synthesizing the desired compound 4'-hydroxy-4-biphenylcarboxylic acid by reacting biphenyl with formic acid and palladium di (trifluoroacetate) However, since it is required to use expensive catalyst and high purification cost due to production of various byproducts, it is difficult to commercialize it. In European Patent No. 240362, 4'-hydroxy-4-biphenyl Carboxylic acid can be synthesized. However, the cost of preparing a bisphenol derivative represented by the following formula (6), which is a raw material, becomes a commercial burden in the production of the target compound 4'-hydroxy-4-biphenylcarboxylic acid.

[Chemical Formula 6]

Therefore, in the liquid crystal, liquid crystal polymer, and high heat-dissipating and high-temperature-resistant resin material industries, which require diverse and efficient physical properties as the electronics industry develops, new 4'- Development of an acid production process is required.

Japanese Patent Application Laid-Open No. 2009-298727 Japanese Patent Registration No. 04243851 Japanese Patent Registration No. 63119440 International Patent Publication No. 2004/76397 European Patent Publication No. 240362

RCS Advances, 2014, 4 (6), 2984 Organic & Bimolecular Chemistry 2014, 12 (25), 4511 Huaxue Shiji 2007, 29 (4), 239 Huaxue Shiji 2005, 13 (6), 614

In contrast, the object of the present invention is to provide a novel process for preparing 4'-hydroxy-4-biphenylcarboxylic acid which is simple in process and high in mass productivity and economical.

A novel process for preparing 4'-hydroxy-4-biphenylcarboxylic acid of the following formula (1) of the present invention is characterized in that it is prepared by hydrolysis from the compound of the following formula (2).

[Chemical Formula 1]

(2)

In Formula 2,

R ¹ is an alkyl, cycloalkyl or aryl group having 1 to 6 carbon atoms,

R is hydrogen or an alkyl group,

X is a leaving group selected from chlorine, bromine, iodine, methane sulfonate, benzene sulfonate, toluene sulfonate,

The quaternary amine salt is an amine salt consisting of three identical or different alkyl groups or aromatic hydrocarbons, or a cyclized aromatic amine salt such as pyridine.

Herein, hydrolysis refers to a reaction in which an alkaline aqueous solution or a mixed solution of an aqueous alkali solution and an organic solvent is heated if necessary. Examples of the alkali used include NaOH, KOH, CsOH, Na ₂ CO ₃ , K ₂ CO ₃ , Cs ₂ is an alkali salt, such as CO _3.

The alkali is used in an amount of 2 to 5 equivalents, preferably 2 to 3 equivalents based on the compound of the formula (2).

The hydrolysis reaction temperature is from 20 to 100 캜, preferably from 60 to 100 캜.

The compound of Formula 2 is prepared by reacting a compound of Formula 3 with a tertiary amine.

(3)

In Formula 3,

R ¹ is an alkyl, cycloalkyl or aryl group having 1 to 6 carbon atoms,

R is hydrogen or an alkyl group,

X is a leaving group such as chlorine, bromine, iodine, methane sulfonate, benzene sulfonate, toluene sulfonate.

The tertiary amine to be reacted with the compound of formula (III) may be a tertiary amine comprising three identical or different alkyl groups or aromatic hydrocarbons; There are cyclized aromatic amines such as pyridine.

The reaction temperature is effectively 20 to 150 ° C, particularly 80 to 120 ° C.

The compound of Formula 3 is prepared by catalytic condensation of a compound of Formula 4 and a compound of Formula 5 below.

[Chemical Formula 4]

[Chemical Formula 5]

In the above formulas,

R ¹ is an alkyl, cycloalkyl or aryl group having 1 to 6 carbon atoms,

R is hydrogen or an alkyl group,

X is a leaving group selected from chlorine, bromine, iodine, methane sulfonate, benzene sulfonate, and toluene sulfonate.

Examples of the catalyst used in the condensation reaction include AlCl ₃ , FeCl ₃ , ZnCl ₂ ; And Lewis acids such as organic sulfonate metal salts such as metal salts of trifluoromethanesulfonate.

The manufacturing process of the present invention is advantageous in that it provides high manufacturing economics due to the simplicity of the process.

Particularly, the production process of the present invention is advantageous in that it is possible to provide a process for economically producing a high purity product by simplifying the synthesis process and convenient purification process.

Hereinafter, the present invention will be described in detail.

The present invention provides a novel process for preparing 4'-hydroxy-4-biphenylcarboxylic acid of the following formula (1).

[Chemical Formula 1]

The preparation process of the present invention can be represented by the chemical reaction path of the following chemical reaction formula (5).

[Chemical reaction formula 5]

Reaction step i

In the above chemical reaction formula 5, in the reaction step i, an acyl group is introduced in order to protect the alcohol group of 4-phenylphenol to obtain the compound of the formula 4. The acylating compound is preferably an alkyl group having 1 to 6 carbon atoms or an aryl group; X < _{1 >} is chlorine, bromine, or an acylating compound; An acid anhydride such as anhydrous propionic acid is used.

NaOH, Na ₂ CO ₃ , KOH, K ₂ CO ₃ and tertiary amine are used as the base used in the reaction step i, and as the reaction solvent used in the reaction step i, esters such as ethyl acetate; Ethers such as diisopropyl ether; Ketones such as acetone; Amides such as dimethylformamide; Nitriles such as acetonitrile; Sulfoxides such as dimethyl sulfoxide are used.

Reaction step ii

In reaction step ii, the compound of formula (IV) is reacted with an acyl compound of formula (5) substituted with a 2-position leaving group to the compound of formula (4) obtained through reaction step i to obtain a compound of formula Hydrogen, an alkyl group having 1 to 6 carbon atoms; X is a good leaving group such as chlorine, bromine, iodine, methane sulfonate, toluene sulfonate, benzene sulfonate, and the compound of formula (5) is an acid chloride having such a leaving group.

The catalyst used in the reaction step ii is a Lewis acid such as AlCl ₃ , FeCl ₃ , ZnCl ₂ and an organic sulfonate metal salt. Examples of the solvent used in the reaction step ii include chlorinated hydrocarbons such as dichloromethane and dichloroethane; Nitroalkanes such as nitromethane are used.

Reaction step iii

In the reaction step iii, the tertiary amine used for synthesizing the compound of formula (2) from the compound of formula (3) is a tertiary amine composed of three alkyl groups which are the same or different from each other; A tertiary amine having at least one aryl group; Tertiary amines constituting the ring such as pyridine are used.

Solvents used in reaction step iii include tertiary amines such as pyridine used to construct compounds of formula 2; Esters such as ethyl acetate; Ethers such as diisopropyl ether; Ketones such as acetone; Amides such as dimethylformamide; Nitriles such as acetonitrile; Sulfoxides such as dimethyl sulfoxide; Water or a mixed solvent of water and an organic solvent is used.

In the reaction step iii, the reaction temperature is effectively 20 to 150 ° C, particularly 80 to 120 ° C.

Reaction step iv

In the reaction step iv, which is the hydrolysis step, an alkali aqueous solution; A hydrolysis reaction using an alkali aqueous solution and a mixed solution of an organic solvent, examples of the alkali to be used in the reaction step iv using such as NaOH, Na ₂ CO _3, KOH, K ₂ CO _3, CsOH, Cs2CO _3, and using The equivalent of the alkali is preferably 2 to 5 equivalents, particularly 2 to 3 equivalents.

Examples of the organic solvent used in mixing with the aqueous alkaline solution in the reaction step iv include alcohols such as methyl alcohol; Amides such as dimethylformamide; Nitriles such as acetonitrile; Sulfoxides such as dimethyl sulfoxide; Ketones such as 2-butanone; Ethers such as diisopropyl ether are used.

The reaction temperature of the hydrolysis reaction in the reaction step iv is 20 to 100 ° C, particularly 60 to 100 ° C.

The acid used as the neutralizing agent to obtain the compound of formula (I) from the hydrolyzed reaction solution in the reaction step iv is an aqueous hydrochloric acid solution; Inorganic acids such as aqueous solutions of bromic acid; Organic acids such as acetic acid are used.

The 4'-hydroxy-4-biphenylcarboxylic acid according to the present invention can be used as a high-functional material such as a liquid crystal, a liquid crystal polymer, and a high heat dissipation high heat-resistant resin, and will be specifically described in the following examples. However, the following examples are intended to illustrate the present specification, and the scope of the present specification is not limited thereto.

≪ Example 1 >

(Preparation Example 1) Preparation of 4-acetoxybiphenyl

30 g of 4-phenylphenol was dissolved in 120 ml of dichloromethane, and 21.6 g of triethylamine was added. After cooling to 10, 18.5 g of acetic anhydride was dropped dropwise over 30 minutes. After stirring for 4 hours, it was confirmed that 4-phenylphenol was consumed by thin layer chromatography analysis, and the mixture was adjusted to pH 2 with 10% aqueous hydrochloric acid solution and layered. The organic layer was washed with 120 ml of water, layered, and then the water of the organic layer was removed with anhydrous sodium sulfate. After the anhydrous sodium sulfate was filtered off, the filtrate was concentrated at normal pressure and crystallized with isopropanol, followed by filtration and drying to obtain 35.1 g of an off-white 4-acetoxybiphenyl (yield: 93.8%).

2H), 7.32-7.46 (m, 3H), 7.55-7.60 (m, 4H), 7.38-7.30 (m,

(Preparation Example 2) Preparation of 4-benzoyloxybiphenyl

(Preparation Example 1), 30.5 g of 4-phenylphenol, 21.6 g of triethylamine and 25.5 g of benzoyl chloride to obtain 44.5 g of an off-white 4-benzoyloxybiphenyl (yield: 92%).

1H NMR (300 MHz, DMSO d6)? Ppm: 7.31-7.66 (m, 12H), 8.22-8.24 (d, 2H)

≪ Example 2 > Preparation of compound of formula (3)

(Preparation Example 3) Preparation of 4-acetoxy-4 '- (2-chloroacetyl) biphenyl

12.5 g of 4-acetoxybiphenyl prepared in Preparation Example 1 and 9.9 g of 2-chloroacetyl chloride were dissolved in 80 ml of dichloromethane, cooled to 5 캜 or lower, and 17.9 g of anhydrous aluminum chloride was added thereto while maintaining the temperature at 10 캜 or lower. After stirring for 4 hours and confirming that the raw materials are completely consumed by gas chromatography analysis, 200 ml of a 5% hydrochloric acid aqueous solution is added and stirred for 3 hours. After the mixture was allowed to stand for 2 hours, the organic layer was separated. To the organic layer was further added 200 ml of water. The mixture was stirred for 1 hour and allowed to stand for 1 hour. The organic layer was separated, and anhydrous sodium sulfate was added thereto and sufficiently stirred to remove water in the organic layer, followed by filtration. The organic layer was heated and distilled to concentrate most of the solvent. 100 ml of isopropanol was added to crystallize it, followed by filtration and drying under atmospheric pressure to obtain an off-white powder of 15.2 g of 4-acetoxy-4'- (2-chloroacetyl) g (89.2% yield).

1H NMR (300 MHz, DMSO d6) [delta] ppm: 2.26 (s, 3H), 5.19 (s, 2H), 7.21-7.24 (d, 2H), 7.75-7.88 ), 8.0-8.04 (d, 2H)

(Production Example 4) Production of 4-benzoyloxy-4 '- (2-chloroacetyl) biphenyl

Benzoyloxybiphenyl prepared in Preparation Example 2, 9.9 g of 2-chloroacetyl chloride, and 17.9 g of anhydrous aluminum chloride. The resultant product was analyzed by gas chromatography and found to have a purity of 88.2% -Benzoyloxy-4- (2-chloroacetyl) biphenyl (88.6% yield).

2H NMR (300 MHz, DMSO d6)? Ppm: 4.75 (s, 2H), 7.33-7.36 (d, 2H), 7.51-7.56 , 2H), 8.22 ~ 8.25 (d, 2H)

Example 3 Preparation of Compound of Formula 2

(Preparation Example 5) Preparation of 4-acetoxy-4 '- (2-pyridinium acetyl) biphenyl chloride

15.2 g of 4-acetoxy-4 '- (2-chloroacetyl) biphenyl prepared in Preparation Example 3 was added to 60 ml of pyridine and the mixture was refluxed for 3 hours. The thin layer chromatography (ethyl acetate 1: Respectively. The reaction solution was cooled to room temperature, filtered, washed with 50 ml of ethyl acetate and dried at 60 to 8 hours to obtain 15.9 g (82.2% yield) of 4-acetoxy-4 '- (2-pyridinium acetyl) ≪ / RTI >

2H NMR (300 MHz, DMSO d6)? Ppm: 2.27 (s, 3H), 6.59 (s, 2H), 7.25-7.28 (d, 2H), 7.81-7.84 ), 8.1-8.33 (d, 2H), 8.23-8.28 (t, 3H), 8.68-8.74

(Preparation Example 6) Preparation of 4-acetoxy-4 '- [2- (4-methylmorpholinium) acetyl] biphenyl chloride

15.2 g of 4-acetoxy-4 '- (2-chloroacetyl) biphenyl prepared in Preparation Example 4 was added to 60 ml of 4-methylmorpholine and refluxed for 3 hours to obtain a thin layer chromatography (ethyl acetate 1: The analysis confirmed that the raw materials were exhausted. The reaction solution was cooled to room temperature, filtered, washed with 50 ml of ethyl acetate and dried at 60 to 8 hours to obtain a brown powder of 4-acetoxy-4 '- [2- (4-methylmorpholinium) acetyl] biphenyl chloride 17.1 g (83.4% yield).

1H NMR (300 MHz, DMSO d6)? Ppm: 2.31 (s, 3H), 3.45 (s, 3H), 3.73-4.1 (m, 8H), 5.52 (s, 2H), 7.28-7.31 7.84-7.86 (d, 2H), 7.94-7.97 (d, 2H), 8.09-8.12 (d, 2H)

≪ Example 4 >

(Preparation Example 7) Preparation of 4'-hydroxy-4-biphenylcarboxylic acid

Acetoxy-4 '- (2-pyridinium acetyl) biphenyl chloride (13.6 g) prepared in Preparation Example 5 was added to 300 ml of water, and 6.5 ml of a 50% aqueous sodium hydroxide solution was added thereto, followed by refluxing for 3 hours. After confirming that 4-acetoxy-4 '- (2-pyridinium acetyl) biphenyl chloride was consumed by analysis, it was cooled to room temperature. The pH of the cooled aqueous solution was adjusted to pH 2 by dropwise addition of a concentrated hydrochloric acid aqueous solution while vigorously stirring. After 1 hour of further stirring, the resulting solid was filtered, washed with 50 ml of 50% acetone aqueous solution and then dried at 80 for 8 hours to obtain a light brown powder of 98.5% purity. Gas chromatograph analysis 4'-hydroxy-4-biphenylcarboxylic acid 6.9 g (87.1% yield) was obtained.

2H), 7.69-7.72 (d, 2H), 7.95-7. 98 (d, 2H), 7.60-7.40 (d,

(Preparation Example 8) Preparation of 4'-hydroxy-4-biphenylcarboxylic acid

Prepared by the method of Preparation 7 from 17.1 g of 4-acetoxy-4 '- [2- (4-methylmorpholinium) acetyl] biphenyl chloride prepared in Preparation Example 6 to obtain a light brown powder of 4'- To obtain 6.8 g (86.9% yield) of 4-biphenylcarboxylic acid.

2H), 7.69-7.72 (d, 2H), 7.95-7. 98 (d, 2H), 7.60-7.40 (d,

Claims (10)

Hydroxy-4-biphenylcarboxylic acid represented by the following general formula (1), which is produced through hydrolysis reaction from a compound represented by the following general formula (2):
[Chemical Formula 1]

(2)

In Formula 2,
R ¹ is an alkyl, cycloalkyl or aryl group having 1 to 6 carbon atoms,
R is hydrogen or an alkyl group,
X is a leaving group selected from chlorine, bromine, iodine, methane sulfonate, benzene sulfonate, toluene sulfonate,
The quaternary ammonium moiety is ammonium, or pyridinium, containing three identical or different alkyl groups. The process for producing 4'-hydroxy-4-biphenylcarboxylic acid according to claim 1, wherein the hydrolysis is carried out in an aqueous alkali solution or a mixed solution of an aqueous alkali solution and an organic solvent. The method of claim 2, wherein 4'-hydroxyphenyl, characterized in that the alkali used for the hydrolysis is selected from the group consisting of NaOH, KOH, CsOH, Na ₂ CO _3, K ₂ CO _3, and Cs ₂ CO ₃ -4-biphenylcarboxylic acid. 4. The process for producing 4'-hydroxy-4-biphenylcarboxylic acid according to claim 2 or 3, wherein the alkali used in the hydrolysis is used in an amount of 2 to 5 equivalents based on the compound of formula Way. The process for producing 4'-hydroxy-4-biphenylcarboxylic acid according to claim 1, wherein the hydrolysis reaction is carried out at 60 to 100 ° C. The method of claim 1, wherein the compound of formula (2) is prepared by the reaction of a compound of formula (3) with a tertiary amine.
(3)

In Formula 3,
R ¹ is an alkyl, cycloalkyl or aryl group having 1 to 6 carbon atoms,
R is hydrogen or an alkyl group,
X is a leaving group selected from chlorine, bromine, iodine, methane sulfonate, benzene sulfonate, and toluene sulfonate. The method of claim 6, wherein
The tertiary amine to be reacted with the compound of formula (III) is a tertiary amine consisting of three identical or different alkyl groups; Or 4-hydroxy-4-biphenylcarboxylic acid. The process for preparing 4'-hydroxy-4-biphenylcarboxylic acid according to claim 6, wherein the reaction between the compound of formula (3) and the tertiary amine is carried out at 80 to 120 ° C. 9. The process according to any one of claims 6 to 8, wherein the compound of formula (3) is prepared by catalytic condensation of a compound of formula (4) and a compound of formula Preparation of biphenylcarboxylic acid:
[Chemical Formula 4]

[Chemical Formula 5]

In the above formulas,
R ¹ is an alkyl, cycloalkyl or aryl group having 1 to 6 carbon atoms,
R is hydrogen or an alkyl group,
X is a leaving group selected from chlorine, bromine, iodine, methane sulfonate, benzene sulfonate, and toluene sulfonate. The process for producing 4'-hydroxy-4-biphenylcarboxylic acid according to claim 9, wherein the catalyst used in the catalytic condensation reaction is a Lewis acid catalyst.