JPS58128341A - Preparation of propionic ester from unsaturated alcohol containing chlorine - Google Patents

Abstract

PURPOSE:To obtain the titled substance useful as a raw material for organic synthetic intermediates, agricultural chemicals, food-type attractants and flame retardants, etc. in high purity and yield, by reacting an unsaturated alcohol containing chorine with propionic acid anhydride in the presence of phosphoric acid. CONSTITUTION:Phosphoric acid as an assistant is added to a mixture of an unsaturated alcohol, containing chlorine, and expressed by formulaI(R1 and R2 are H or alkyl) is reacted with propionic acid anhydride (an esterification reagent) at a low temperature (0-10 deg.C), and the reaction is carried out under heating to suppress the formation of diene compounds and resinification by side reactions and obtain advantageously the compound of formula II. Phosphoric acid, metaphosphoric acid and polyphosphoric acid can be used alone or together, and phosphoric acid of high purity is unsuitable for an easily dehydrated compound. Generally, phosphoric acid of up to 85% purity is suitable.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a method for producing a propionate ester of an unsaturated chlorine-containing alcohol, which is characterized by an unsaturated chlorine-containing ester represented by the general formula C]-R2 (hydrogen atom or alkyl group). Producing propionic acid ester of unsaturated chlorine-containing alcohol represented by the general formula % (in which E and R2 have the same meanings as above) by reacting alcohol and propionic anhydride in the presence of phosphoric acid. It's about how to do it.

The present inventor has researched esterification reagents and auxiliary agents for unsaturated chlorinated alcohol, and found that since the raw material unsaturated chlorinated alcohol is dehydrated or turned into a resin by the added auxiliary agent, these reactions can be prevented and high yields achieved. The propionic acid ester of an unsaturated chlorine-containing alcohol was obtained using the following method.As a result of the present method, it was found that by adding phosphoric acid to a mixture of an unsaturated chlorine-containing alcohol and propionic anhydride at a low temperature, and then further heating the reaction. discovered a method for producing the desired ester with high purity and high yield by preventing the formation of by-product diene compounds.

When a propionic acid ester is produced by depyonylating a hydroxyl group of an alcohol, various auxiliary agents are used as an esterification agent together with propionic acid, propionic anhydride, propionyl chloride, and the like. Depending on the substance to be propionized, it is necessary to select a combination of reagents and auxiliary agents. When propionylating unsaturated chlorine-containing alcohols, side reactions such as dehydration and resin formation are likely to occur.
It is difficult to obtain the desired ester with good purity and high yield without producing by-products such as diene compounds.

The combination of the esterification reagent (anhydride) ``robionic acid'' and the auxiliary agent (phosphoric acid) according to the method of the present inventor can sufficiently prevent the four-tone formation and resin formation of the diene compound produced as a by-product, and can be used in combination with other reagents. This method corrects the drawbacks of the method using auxiliary agents.

According to the method of the invention, the ratio of propionic anhydride as an esterifying agent to unsaturated chlorine-containing alcohol as a raw material is up to 10 mo)/7 liters. However, the appropriate amount of propionic anhydride to be used is usually an S to O molar equivalent.

Further, as the auxiliary phosphoric acid to be added, phosphoric acid, metaphosphoric acid, and polyphosphoric acid can be used alone or in combination. For compounds having structures that are particularly susceptible to dehydration, highly pure phosphoric acid is inappropriate, and phosphoric acid of up to 5% g is generally suitable.

The amount of phosphoric acid added is determined by adding it to unsaturated chlorine-containing alcohol.
About 700% by weight is sufficient, and if the amount of phosphoric acid added is large, diene compounds will be produced as by-products, so it is necessary to keep it as low as possible. The temperature when adding crushed phosphoric acid is 0 to 10°
A temperature of less than 70°C is suitable, and a temperature of 70°C or higher similarly promotes the formation of diene compounds and resin formation.

The heating time after adding the auxiliary agent to the esterification reagent is 7~
A suitable time is 70 hours, and the reaction is usually completed within 3 hours.

The shorter the reaction time, the better; if the reaction time is longer, diene compounds and the like may be generated.

The ester obtained by the method of the present invention is useful as a raw material for organic synthesis intermediates, agricultural chemicals, total attractants, flame retardant treatment agents, and the like.

The present invention will be specifically explained by the following examples.

Example/CCI□=CClCH20Hg, 079 (00,!
;-r=w ) and propionic anhydride 39.0! ;yC
After cooling a mixture of 030 mol) to 0-5'C, g
s% phosphoric acid (2.2% fZ<,00/tamol) was added dropwise over 30 minutes.

After the dropwise addition, the mixture was further heated and reacted in hot water bath 1 (70 to 95"C) for 3 hours. The reaction mixture was placed in ice water and decomposed, and then
Extract with carbon tetrachloride. The extract is washed with an acidic sodium hydrogen aqueous solution and a saturated sodium chloride aqueous solution and then dried. Carbon tetrachloride is recovered from the extract and crude oil/41.
Got 0/9. Fractional distillation of crude oil L bp Otsu 3.0 ~ A l
,, 0°C/3mmHg, (d,”73g,!0,
)? :/g/2, chlorine content 41g%) ester C]3CH2CO・0CH2CCCCl2 fraction 3
309 (yield Otsu 90%) was obtained.

Example 2 13 CCI2 =CC1-CHOHI7. ! ;'19 (
010 mol) and propionic anhydride 71! i>0ri9
After cooling the mixed solution of CO (0 mol) to o = s'c, gs% phosphoric acid 41.3-I9 (0039 mol) was added dropwise over 30 minutes.

After dropping, the mixture was further reacted in a hot water bath for 3 hours. After the reaction,
The reaction mixture was decomposed in ice water and then extracted with carbon tetrachloride. After washing and drying the extract as shown in Example/
Carbon tetrachloride was recovered and crude oil 3g'729 was obtained. Crude oil is fractionated to bp3/, 0~S20°C/, 2W shoulder Hg <
4"y, ,2y Otsu3, h:/Gua Otsu01 chlorine content 4t!;,941%) unsaturated 01(3 1 Stell C1(3CH2Co-0-ell(-CC=C
C z/3332 (yield 707%) was obtained.

Example 3 crt□CI:'f3 CCl2 =CC1-CI"JOl-11g, 9 3
After cooling a mixture of 7 g09y (060 mol) of y-(0/0 mol) propionic anhydride to θ~3'C, 3 g5% phosphoric acid S/ri (0039 mol) was added.
Drop in 0 minutes.

After the dropwise addition, the reaction was continued for 3 hours on a hot bath. The reaction mixture was decomposed in ice water and extracted with carbon tetrachloride. The extract was washed 1 and dried as shown in Example 1, and then carbon tetrachloride was recovered to obtain 3g2θy of crude oil. Fractionally distill the crude oil and bp Otsugo-Otsug3°C/3關IQ; (d,”/2Otsu09,)17/
Gua S, chlorine content 327%) unsaturated ester CH2CH3 CH3CH2C0・OCH-CC, CC on 2 i3
Otsu 5F (yield Otsu 9S%) was obtained.

Example CH2CH2CH3 CC1,, = CC]--CIiO)I 2033
9 (0/0 mo tv) and propionic anhydride 7gO? After cooling the mixture of ICO Otsu Omo/I/) to 0-3°C, add g5% phosphoric acid! (003 tamole) was added dropwise over 30 minutes.

After the dropwise addition, the mixture was heated and reacted in a bath for 3 hours. The reaction mixture was decomposed in ice water, and then extracted with carbon tetrachloride. The extract is washed and dried as shown in Example 1, and then carbon tetrachloride is recovered. Crude oil 22329 was obtained. Fractional distillation of crude oil to bpg
7o～KgK"C/3hoHg(da' 123 Otsu A
,) t: /, 11739) Chlorine content rate og41%
) unsaturated ester CH2CH2C■(3 CF2Cl(□CO,OCR-CC]-2CC]-2/
2 (yield S zo 2%) was obtained on the left.

Claims (1)

[Scope of Claims] A general formula characterized in that an unsaturated chlorine-containing alcohol represented by the general formula % and propionic anhydride are reacted in the presence of phosphoric acid (R in the formula and R2 are as above) A process for producing propionate esters of unsaturated chlorine-containing alcohols, which have the same meaning.