CS207597B2 - Method of making the dihalogenvinyl-gama-butyro-laktons - Google Patents

Description

The present invention relates to a process for the preparation of the partially known dihalo-vinyl-γ-butyirolaictones.

Dihalvinyl-γ-butyrolactones are valuable products for the production of the partially known dihalogeninylcyclopropanecarboxylic acid esters which are used as insecticides. These manufacturing processes are described in DOS No. 2,710,974.

Vinyl-substituted β-butyrolactomas, as well as a process for their preparation, are already known (see DOS 2,461,525 and 2,509,576). However, the processes described are poorly economical and, moreover, they are limited to vinyl-substituted or dialkyl vinyl-substituted γ-butyrolactones.

In addition, it is known that 4-methyl-3- (2 ', 2'-dichlorotivinyl) -γ-vialerolactone is formed as a byproduct in the saponification of 2,2'-diimethyl-3- (2', 2'-di-vinyl vinyl) cyclopropain 1-carboxylic acids (see Peistic. Sci. 1974, 5, 792-793).

Further, a process for the preparation of 4- (2‘, 2‘-dihalo-vivinyl) -3,3-dimethyl-yl-γ-butyirolactones is known (see DOS 2,623,777). The process starting from dimedoin can only be carried out uneconomically and in addition does not lead to any 3-dihalo-vinyl-γ-butyrolactones.

We have now found a process for the preparation of the partially known long-halogenated vinyl-γ-butyrolactones of the general formula I

in which

Hal means the same or different fluorine, chlorine or bromine atoms,

R ¹ and R ² represent the same or different radicals from the group consisting of hydrogen or (C 1 -C 4) -alkyl or, together with the adjacent carbon atom, form a cycloaliphatic ring of up to 7 carbon atoms, characterized in that the compound of formula ¹

207397

C 1 -C 4 -alkyl, is prepared by the oxirane of formula IV

in which

Hal, R ^1, R ² have the above meanings, and

R ³ is hydrogen, C 1 -C 4 alkyl, optionally heated in the presence of a base and (optionally in the presence of a diluent) to 0 to 250 ° C.

According to the invention, novel dihalvinyl-γ-butyrolactones of the formula I are also prepared in which

Hal, R ¹ and R ² have the meanings given under formula I, but with the proviso that when both Hal means chlorine,

R ¹ is hydrogen or C 2 -C 4 alkyl, and

R ² represents a group having 1 to 4 carbon atoms, since together with R ¹ and the adjacent carbon atom they form a cycloaliphatic ring having up to 7 carbon atoms.

Compounds of formula II in which Hal, R ^1, R ² and R ³ have the abovementioned meaning, are oxytocic new. Compounds of · the formula II in which Hal, R ¹ and R ² have the above meanings and R ³ is hydrogen, are produced that compounds of formula II wherein R ³ is an alkyl group having 1 to 4 carbon atoms, Soap. Those compounds of formula II wherein R ³ is alkyl wherein

Hal, R ¹ and R ² have the above meanings, is reacted with a malonic acid ester of formula V

COOR ³

OF

CHa, \

COOR ³ (V) where

R ³ has the abovementioned meaning, in the presence of baize and optionally in the presence of a diluent.

Oxiranes of the formula IV in which Hal, R ¹ and R ² have the abovementioned meaning, are novel compounds.

The process of their preparation is the subject of the invention. No. 207,598.

When 4-methyl-3- (2 ', 2'-dichloro-vinyl) -yl-olactone-2-carboxylic acid 4-methyl-3- (2', 2'-dichloro-vinyl) -carboxylic acid is used as starting material in the process of the invention, the following reaction scheme is shown. :

The starting materials useful in the process of the invention are generally defined by Formula II. In this formula, R ¹ and R ^{2 are} preferably methyl and R ³ is hydrogen. The compounds of formula II are novel and their preparation is described below.

The process according to the invention is carried out by heating the compounds of the formula II, optionally in the presence of diluents, to a temperature

100 to 250 ° C, preferably at a pressure of 1333 to 100 ° C

101 325 Pa.

Suitable diluents are: hydrocarbons such as toluene, xylene; chlorinated hydrocarbons such as chlorbeinzen, dichlorbeinzen; ethers, such as, for example, diethylene glycol dimethyl ether, glycoldibutyl ether or alcohols such as glycol.

According to another preferred embodiment, the compounds of formula II are heated without solvent. In this case, the compounds of the formula I can be distilled off under a slight vacuum (1333 to 13 332 Pa) and thus simultaneously purified. However, it is also possible to dispense with distillation and purify the resulting compounds of formula I by recrystallization when the compounds of formula II are heated.

If 4-ethyl-3- (2‘, 2‘-dibromivinyl) -y-valerolactone-2-carboxylic acid ethyl ester is used as the starting material in the process of the invention, the reaction scheme may be illustrated as follows:

£ OOC ₂ H _£

The starting materials used in this process are defined by Formula II wherein R ¹ and R ² are preferably methyl groups.

This process is carried out by compounding the compounds of one of the generally conventional ester saponification processes in the presence of a diluent to the carboxylic acid of formula II. The saponification can be carried out in basic form in an acidic medium. Preferably, it is operated in a basic environment at a pH of greater than 10 and at temperatures between 0 and 100 ° C. The alcohol formed is distilled off and, after saponification, the reaction mixture is acidified to pH > 1 to form the acid of formula II (R ³ = H).

The following lactoines can be advantageously prepared by the process according to the invention:

4-Meithyl-3- (2‘, 2‘-dichlorvinyl) - β-valerolactone,

3- (2 ‘, 2‘-Dichlonvinyil-γ-valerolactol),

3- (2 ', 2'-dichlorvinyl) -χ-butyrolactone,

4-etítyl-3- ^{(2, 2,} _-dichlo) rvinylj-χ-valerolactone,

4,4-Diefhyl-3- (2 ‘, 2‘-dichlorvinyl) -χ-butyrolactone

4-dimethyl-3- (2 ', 2'-DIB ^and romivinyl] -χ-valerolactone,

3- (2 ‘, 2‘-dibromo-vinyl) -χ-valerolakitone,

3- (2 ‘, 2‘-dibromivinyl) -χ-butyrolakitone,

4-ethyl-3- (2 ', 2'-dibromvinyl) -y-valerolactone,

4,4-diethyl-3- (2 ', 2'-dih ^, romivinyl) -χ-butyrolactone,

4-methyl-3- (2‘-chloro-2‘-bromo) -χ-valerolactone,

4-methyl-3- (2'-fluoro-2'-bromo) -χ-valerolactone.

As already mentioned, the dihalogenyl-γ-butyirolactones produced according to the invention serve as intermediates for the production of insecticidally active compounds.

The preparation of these active compounds is illustrated by the following reaction schemes:

0 θ - «W0C, Ws ^{x =} = ^/

207537

The 2,2-dimethyl-3- (2 ‘, 2 i -dicyclinyl) cyclopiropanecarboxylic acid m-phenoxybenzyl ester thus obtained is a known insecticidally active compound (cf. DOS 2 326 077).

The following examples illustrate the process of the invention. However, these examples do not limit the invention.

Example 1

4-Methyl-3- (2 ', 2'-dichloro-vinyl) -yl-valerolactone-2-carboxylic acid (91 g) was distilled in a water pump vacuum at 200 ° C oil temperature. 74 g of 4-methyl-3- (2‘, 2‘-dichloro-vinyl-γ-γ-valerolactone, boiling point 160-172 ° C / 3066-4000 Pa) are obtained.

Example 2

Dissolve 11.5 g of sodium in 250 ml of ethanol, add dropwise at room temperature 80 g of diethyl tertiary acid and then potoim; 128 g of 2,2-dimethyl-3- (2 ‘, 2‘-dibromvimyl) oxirane for one hour at 30-35 ° C. The temperature was then maintained at 35 ° C for 4 hours.

To saponify the resulting 4-methyl-3- (2 ', 2'-dibromvinyl) -χ-valerolactom-2-carboxylic acid ethyl ester, 800 ml of 10% sodium hydroxide solution was added to the reaction solution, and the mixture was stirred at room temperature for 12 hours. rooms. Ethanol was distilled off and the reaction solution was acidified with concentrated hydrochloric acid to pH 1. 4-Methyl-2- (2 ', 2'-dibromvinyl) -yl-valerolactone-2-carboxylic acid precipitated with a melting point of 140 ° C. . This acid was filtered off and suspended in o-diililobenzene and heated to 170 ^DEG- 180 ^DEG C. with stirring for 2 hours. Upon cooling, 91 g (about _61/0) of 4-methyl-3- (2 ', 2'-dibromo omivinyl) - / - Valera olaiktoinu mp 115 ° C.

Example 3

11.5 g of sodium are dissolved in 250 ml of ethanol at room temperature was added dropwise 80 g diethylmalonate and then at 40 ^Q C in one hour 83.5 g of 2,2-dimethyl-3- (2 ', 2' The temperature is then maintained at 40 DEG C. for a further 3 hours, after which 800 g of 10% sodium hydroxide solution are added, the mixture is heated to boiling for 2 to 3 hours, the ethanol is distilled off and the pH is adjusted with concentrated hydrochloric acid. After filtration, 4-methyl-3- (2 ', 2'-dichloro (vinyl) - N-valerolacone-1-carboxylic acid) is obtained which melts at 138 ° C after drying.

Claims (1)

SUBJECT Process for the preparation of dihaiogenvinyl - / - butyrolactones of the general formula I A compound of formula II wherein: Hal means the same or different fluorine, chlorine or bromine atoms, R ¹ and R ^Z are identical or different radicals from the group consisting of hydrogen or alkyl having 1 to 4 carbon atoms or together with the adjacent carbon atom forms · cykloalifetický kruih having up to 7 carbon atoms, Hal, R ¹ and R ^z are as defined above, R ³ represents hydrogen or alkyl with 1 to 4 carbon atoms, optionally heated in the presence of a diluent and optionally in the presence of a base at temperatures from 0 to 250 ° C.