JPS6110532A - Production of cyclopentanecarboxylic acid chloride - Google Patents

Abstract

PURPOSE:A 2-halogenocyclohexanone is brought into contact with an inexpensive base in the presence of water and an organic solvent to permit high-efficiency production of the titled compound through simple operations. CONSTITUTION:An alpha-halogenocyclohexanone such as 2-chlorocyclohexanone, alpha- bromocyclohexanone or alpha-iodocyclohexanone is brought into contact with a base such as LiOH, NaOH, Na2CO3 in the presence of water and an organic solvent such as methanol (0.5-10 times the amount of the starting material) at 10-100 deg.C under normal pressure to give a cyclopentanecarboxylate salt. The amount of the base is 1-6 equivalents, preferably 2-4 equivalents based on the starting compound and it is used in an aqueous solution of 10-80wt%, preferbly 30-60wt% concentration.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a new method for producing cyclopentane carboxylate compounds, and more specifically, the present invention relates to a novel method for producing cyclopentane carboxylate compounds, and more specifically, it relates to a method for producing cyclopentane carboxylic acid salt compounds, and more specifically, to produce cyclopentane carboxylate compounds by Faborski reaction in the presence of water and an organic solvent. The present invention relates to a method for producing an acid salt compound.

(Prior art) Conventionally, cyclopentanecarboxylic acid Wofaborski (F
As a synthesis method by rearrangement reaction, 2-halogenocyclohexanone is reacted with an alkali hydroxide in an alcohol solvent [A, Fav
ors+ky at V, Bojoveky, Bu
lx, Soc.

Chin, Fromco, 18.615 (191
5) ), or a method of reacting with sodium alcoholade in an alcohol solvent (Goheen and V
aughan, OrgSyntheses, 59.
37 (1959), R.B. LOftfield.

, T, A, O, S,, υ, 4707 (195
1) ] is known. In both of these methods, the rearrangement reaction is carried out in the absence of almost or no water in the reaction system, and the carboxylic acid ester compound is used as a reaction intermediate, and this is hydrolyzed to form the carboxylic acid compound. This is the way to get it.

(Problems to be solved by the invention) However, these methods require a step of hydrolysis of ester, which makes the process complicated, and the utility costs such as electricity and steam are high (not only do they require a lot of alcohol, but they also require the use of alcohol). The cost of raw materials used is high, and the loss is also large because hydrolysis is not necessarily quantitative.

Therefore, the present inventors conducted extensive studies to improve these drawbacks, and found that even when using an inexpensive base such as sodium hydroxide, Fabolski is extremely efficient when water and an organic solvent coexist as solvents. They discovered that the reaction progresses and completed the present invention.

(Means for Solving the Problems) Thus, according to the present invention, a cyclopentanecarboxylate compound can be produced in high yield by contacting an α-nologone chlorohexanone compound with a base in the presence of water and an organic solvent. A method is provided to obtain it.

Examples of the α-halogenocyclohexanone compound used as a raw material in the present invention include 2-chlorofuclohexanone, α-bromocyclohexanone, α-iodo/clohexanone, and methyl-substituted, ethyl-substituted, butyl-substituted products of these compounds. Alkyl substituents of may be used as well.

In the present invention, the reaction is carried out using such raw materials in the presence of water and an organic solvent. The organic bath agent used is not particularly limited as long as it does not easily react with bases, and specific examples include alcohols such as evaporated methanol, ethanol, butanol, hexanol, octatool, and lauryl alcohol. , ethers such as diethyl ether, dibutyl ether, diphenyl ether, and tetrahydrofuran, nitriles such as acetonitrile and benzonitrile, benzene, toluene,
Examples include hydrocarbons such as xylene, hexane, and cyclohexane. These organic solvents can be used in combination of two or more types if necessary. Among these organic solvents, it is preferable to use polar solvents, particularly hydrophobic alcohols, from the viewpoint of improving the yield.

The amount of such organic solvent to be used can be selected as appropriate, but it is usually 0 to 2-no-logonone-chlorohexanone compound as the raw material.
, 5 to 10 times by weight, preferably 1 to 5 times by weight, and as the amount used decreases, it becomes difficult to control the reaction and high boiling point by-products increase. The aqueous base solution may be present from the beginning, or part or all of it may be added simultaneously with the 2-halogenocyclohexanone compound as a raw material.

On the other hand, the amount of water used in the present invention may be appropriately selected, but is usually 0.15 to 3 times the weight of the 2-logenocyclobentanone compound, preferably 0.3 times the amount of water used in the present invention.
~2 times by weight, and if the amount of water used is too large, the yield may decrease. Such water is usually supplied as an aqueous solution of a base, but it can also be supplied independently of the base if necessary.

The base used in the present invention may be any base that is commonly used in Faborski reactions, and specific examples include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide, sodium carbonate, potassium carbonate, - Carbonates such as potassium bicarbonate are exemplified, and alkali metal hydroxides are particularly preferred. Such a base is usually used in an amount of 1 to 6 equivalents, preferably 2 to 4 equivalents, based on the 2-halogenocyclohexanone compound as a raw material, and is used as an aqueous solution of 10 to 80% by weight, preferably 50 to 60% by weight.

Although the reaction conditions employed in the present invention are not particularly limited, the reaction temperature is usually 10°C to 100°C, preferably 25°C to 80°C, under atmospheric pressure, and water, The 2-halogenocyclohexanone compound is heated in the presence of an organic solvent and a base for 15 minutes to 5 hours, preferably 50 minutes to 6 hours.
Added over time.

After the reaction is complete, the cyclopentane carboxylate compound produced is separated from the aqueous or organic phase in a conventional manner. Furthermore, if necessary, the cyclopentanecarboxylic acid compound can be obtained by hydrolysis without isolation.

(Effects of the Invention) Thus, according to the present invention, a cyclopentane carboxylate compound can be obtained efficiently with simple operations and using an inexpensive base.

The present invention will be explained in more detail with reference to Examples below. Note that parts and parts in Examples and Comparative Examples are based on weight unless otherwise specified.Example 1 In a stainless steel reactor equipped with a stirrer and a cooling reflux device, 200 parts of a 50% aqueous solution of sodium hydroxide (NaOH2,
5 mol) and 500 parts of roohexanol were added, and while stirring at 50"C under atmospheric pressure, 100 parts of 2-chlorocyclohexanone (0.75 mol) was added over 2 hours to react. After the reaction was completed. The mixture was cooled to room temperature and separated into an aqueous phase and an organic phase to obtain 700 parts of a solution of sodium cyclopentanecarboxylate in roohexanol.

Next is sodium cyclobencune carboxylate! In order to measure the yield of , a portion of this Rouhexanol/J solution was taken, cooled to 20°C, and 10% hydrochloric acid was added to it at pH 3.
The mixture was added little by little until the amount of cyclobencune carboxylic acid was reached, converting it to cyclobencune carboxylic acid, which was quantitatively determined by gas chromatography (the conversion of sodium cyclobencune carboxylate to cyclopentane carboxylic acid by a strong acid proceeds quantitatively).

As a result, the molar yield of sodium cyclopentanecarboxylate was 595 yen. In addition, 36% of adipoint was obtained as a by-product in this N-Aborski rearrangement reaction.

Further, 500 parts of acetone was added to 100 parts of the rhohexanol solution of sodium cyclopenta7carboxylate to precipitate crystals, and the crystals were filtered and separated.
It was dried under reduced pressure at 0°C. The obtained crystals were 8.7 parts, and H
-NMR and E-R spectrum confirmed that it was sodium cyclopentanecarboxylate. The molar yield by this quantitative method was 593%.

Example 2 Into the same reactor as in Example 1, 200 parts of a 40% sodium hydroxide water bath solution (2.0 moles of NaOH), 200 parts of rubutanol, and 300 ieJ of toluene were added.

Then, 100 parts (0.75 mol) of 2-chlorocyclohexanone was added to the mixture under stirring at 50 DEG C. under atmospheric pressure over 2 hours, and the mixture was reacted. After the reaction was completed, 650 parts of water was added to dissolve the precipitated salt while cooling to room temperature, and the aqueous phase and organic phase were separated to obtain 650 parts of an aqueous solution of sodium cyclopentanecarboxylate at °C.

A portion of this aqueous solution was taken and sodium cyclopentanecarboxylate was quantitatively determined by gas chromatography in the same manner as in Example 1 to obtain a molar yield of 525.

Example 6 150 parts of IJum 667% aqueous solution (↑Jp
The reaction was carried out in the same manner as in Example 1, except that 2.5 mol of OR, 2.5 mol) was used. As a result, the molar yield of sodium cyclopentanecarboxylate was 653% as determined by gas chromatography.

Example 4 A reaction was carried out in the same manner as in Example 1 except that tetrahydrofuran was used in place of roohexanol. As a result, the molar yield of sodium cyclopentanecarboxylate was 48.5% as determined by gas chromatography.

Comparative Example 1 102 parts (15 moles) of sodium ethoxide and 500 parts of ethanol were placed in a stainless steel reactor equipped with a stirrer and a cooling reflux device, and the mixture was stirred at 50°C under atmospheric pressure.
100 parts (0.75 mol) of chlorocyclohexanone
It was added and reacted over time.

After the reaction was completed, ethanol was distilled off under atmospheric pressure.

This reaction produced cyclopentanecarboxylic acid ethyl ester. The ethyl ester produced by this reaction was extracted with ether, and the molar yield determined by gas chromatography was 53.

After distilling off the ethanol, 500 parts of water was added and heated at 70°C for 1 hour to hydrolyze the ester. At this time, after extraction with 200 parts of toluene to remove the ethanol produced, cyclobencune carboxylic acid was quantitatively determined by gas chromatography in the same manner as in Example 1, and the molar yield was 4.
Obtained 51%.

Comparative Example 2 Sodium hydroxide 50% in a stainless steel reactor equipped with a stirrer
Add 200 parts (2.5 mol) of an aqueous solution of
2-chlorocyclohexanone 100% while stirring at °C.
(075 mol) was gradually added and reacted. At this time, there was a great deal of heat generation, and in order to control the reaction temperature, it took 4 hours to add the entire amount of α-chlorocyclohexanone.

After the reaction was completed, 150 parts of water was added to dissolve the precipitated salt, and 450 parts of sodium cyclopentanecarboxylate was prepared as an aqueous solution.
The obtained product was quantitatively determined by gas chromatography in the same manner as in Example 1, and the molar yield was 28.5.
I got %.

Claims (1)

[Claims] 1. A method for producing a cyclopentanecarboxylate compound, which comprises contacting a 1,2-halogenocyclohexanone compound with a base in the presence of water and an organic solvent.