CH636095A5 - Process for the preparation of dihalovinyl-gamma-butyrolactones - Google Patents

Abstract

Dihalovinyl- gamma -butyrolactones, some of which are known, of the general formula I <IMAGE> in which the substituents are defined in Claim 1, are obtained by reacting an oxirane with malonic esters in the presence of a base and heating the reaction mixture without isolating intermediates. Dihalovinyl- gamma -butyrolactones are valuable intermediates in the preparation of halovinylcyclopropanecarboxylates, some of which are known, which are used as insecticides.

Description

The present invention relates to a process for the preparation of partially known dihalogenvinyl-y-butyro-lactones.

Dihalogenvinyl-y-butyrolactones are valuable intermediates for the preparation of the partially known dihalogen-vinylcyclopropanecarboxylic acid esters which are used as insecticides. These manufacturing processes are the subject of another, unpublished, new application (Le A 17 866).

Vinyl-substituted y-butyrolactones and processes for their preparation have already become known (see German Offenlegungsschriften 2,461,525 and 2,509,576).

However, the processes described there are not very economical and are also restricted to vinyl-substituted or dialkyl-vinyl-substituted y-butyrolactones.

It has also become known that 4-methyl-3-

Hal

in which

Hai stands for identical or different F, Cl or Br radicals, R1 and R2 stand for identical or different radicals of group 30 hydrogen or Ci-4-alkyl or together with the adjacent carbon atom form a cycloaliphatic ring with up to 7 carbon atoms. Form atoms,

is characterized in that an oxirane of the general formula IV

IV

in which

Shark, R1, R2 have the meaning given above with malonic esters of the general formula V

45

CH2

OOR3

-COOR3

50 in which

R3 represents Ci-C4-alkyl,

in the presence of a base and, if appropriate, in the presence of a diluent, and the reaction mixture is heated 55 without isolation of intermediates.

The process according to the invention allows - starting from the oxiranes of the formula IV - an economical production of the partially known halovinyl-substituted-y-buty-60-rolactones by reaction with malonic esters of the formula V.

If 2,2-dimethyl-3- (2 ', 2'-dichlorovinyl) -oxirane and diethyl malonate are used as starting materials in the process according to the invention, the course of the reaction can be represented by the following reaction scheme:

3rd

636095

elei

H3 CH.

+

CH

, COOC2H5 COOC2H3

ci-c

CH.

CH.

In the course of this process, the compounds of the general formula III are formed as intermediates

Shark shark r '

: oor-

III

in which

Hai, R1, R2 have the meaning given above and R3 is Ci-C4-alkyl, and the general formula II

.COOK

II

in which

Hai, R \ R2 have the meaning given above, but are not isolated.

The starting materials used in the process according to the invention are defined by the formulas IV and V. Compounds in which R1 and R2 are methyl are preferably used here. R3 preferably represents methyl or ethyl. The compounds of formula IV are new, their preparation is described below.

The compounds of formula V are known.

The process according to the invention is preferably carried out by first preparing the sodium or potassium salt of the malonic ester of the formula V, which is usually carried out with alcoholates, such as sodium methylate or sodium ethylate. Alcohols such as methanol or ethanol are preferably used as solvents. Then at 20-100 ° C, but preferably at 35-50 ° C, the oxirane of the general formula IV is added dropwise and the reaction solution for some time, usually about 1-6

ch.

Hours held at the selected reaction temperature, io The compound of formula III has formed. The ester component of the compound of the formula III is then saponified in the reaction medium by allowing it to cool, adding water or aqueous alkali, such as sodium hydroxide solution or potassium hydroxide solution, a pH> 10 being reached. The mixture is then stirred at temperatures of 0-100 ° C for about 1-4 hours. Then the alcohol present as a solvent is distilled off and then acidified to a pH <1 with acid such as hydrochloric or sulfuric acid. The compound of formula II is formed as the water-insoluble product. This is now preferably filtered off and, if appropriate in the presence of a diluent, heated.

The following lactones can preferably be prepared by the process according to the invention:

25th

4-methyl-3- (2 ', 2'-dichlorovinyl) -y-valerolactone 3- (2', 2'-dichlorovinyl) -y-valerolactone

3- (2 ', 2' dichlorovinyl) y-butyrolactone

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

30 4,4-diethyl-3- (2 ', 2'-dichlorovinyl) -y-butyrolactone 4-methyl-3- (2', 2'-dibromovinyl) -y-valerolactone 3 - (2 ', 2' - dibromo vinyl) -y-valerolactone 3 - (2 ', 2' -dibromo vinyl) -y-butyrolactone 4-ethyl-3- (2 ', 2' -dibromovinyl) -y-valerolactone 35 4,4-diethyl-3 - (2 ', 2'-dibromo-vinyl) -y-butyrolactone 4-methyl-3- (2'-chloro-2'-bromo) -y-valerolactone 4-methyl-3- (2'-fluoro-2'- brom) -y-valerolactone

As already mentioned, the oxiranes of the general formula IV are new.

They can be obtained by using compounds of the general formula VI

45

H R1

I I

HabC-CHi-C - C-R2

I I

Shark OH

VI

in which Hai, R1, R2 have the meaning given above, in the presence of a diluent and a catalyst. If 2-methyl-3,5,5,5-tetrachloropentanol (2) is used as the starting material, the course of the reaction can be represented by the following formula:

CC13-CH2-CHC1-C-CH3 OH

This course of the reaction was surprising. It runs through halogen elimination of hydrogen from compounds of general formula VI to compounds of general formula IX

,1

Hal ^ C-CH

ix

636095

4th

in which

Hai, R1, R2 have the meaning given above, and further elimination of hydrogen halide to give compounds of the general formula IV.

While the elimination of the first mole of hydrogen halide to give the compounds of the general formula IX could be expected, it was surprising that the elimination of hydrogen halide from the compound IX would also take place in good yield and without significant side reactions, for the following reasons:

Oxiranes are sensitive to alkalis and lead to further reactions (Houben-Weyl, Methods of Organic Chemistry, Stuttgart 1965, Volume VI, 3, page 376).

Oxiranes are easily reopened with bases (nucleophiles): this produces the alkali-catalyzed diols with water (Houben-Weyl, Vol. VI, 3, page 457), with amines one obtains amino alcohols.

If the oxirane contains a tertiary carbon atom adjacent to the oxygen, as in the particularly preferred example Ri = R2 = CH3, hydrolytic cleavage takes place even at room temperature (Houben-Weyl, Volume VI, 3, page 454).

It was therefore to be expected that under the influence of the base, which is intended to split off hydrogen halide from compounds of the general formula IX, the oxirane ring would split again and there would be no splitting off of hydrogen halide.

Trihalomethyl groups usually do not react with bases with elimination of hydrogen halide, but ether, carboxylic acid or the like are formed (US Pat. No. 2,581,925, lines 57-62). It is therefore extremely surprising to note that a smooth conversion of the compounds of the general formula IX into compounds of the general formula IV is possible.

The oxiranes are expediently obtained by reacting 1 mol of a compound of the formula IV with at least 2 mol of a base, if appropriate in the presence of a catalyst; if only one mole of a base is used, compounds of the general formula IX are obtained.

The oxiranes are preferably made in aqueous solution, but the use of inert organic solvents such as hydrocarbons, e.g. Benzene or toluene, chlorinated hydrocarbons such as chlorobenzene and ether without disadvantages.

The oxiranes are usually produced using suitable catalysts. Compounds of the general formula X or XI are preferably used as such:

B B

I X |

A-L (+, - C A-N-C XI

D

Y «-i in which

L represents nitrogen or phosphorus and the radicals A, B, C and D independently of one another represent optionally substituted alkyl, aralkyl or aryl, or two adjacent radicals, A, B, C and D together with the central atom L and optionally further heteroatoms Form heterocycle and

Y represents a halide, hydrogen sulfate or hydroxyl ion.

Some of the catalysts of the general formula X are known or can be prepared by known processes (Houben-Weyl, Volume XI, 2, page 587 ff .; Georg-Thieme-Verlag, Stuttgart 1958).

Catalysts of the general formula X in which

A, B, C, D for alkyl with 1-18 C atoms, in particular methyl, ethyl, propyl, butyl, hexyl, dodecyl, octadecyl, for benzyl, which is optionally substituted by C 1 -C 4 -alkyl, alkoxy or halogen, stand.

Also preferred are catalysts of the general formula XI,

in which

A, B and C are alkyl with 1-18 C atoms, in particular methyl, ethyl, propyl, butyl, hexyl, dodecyl, octadecyl and benzyl.

The following are particularly preferred representatives of the catalysts to be used in the production of oxirane:

Tetraethylammonium chloride,

Tetrabutylammonium chloride,

Tetrabutylammonium bromide,

Tetrabutylphosphonium chloride,

Benzyltriethylammonium chloride,

Phenylbenzyldimethylammonium chloride,

Benzyldodecyldimethylammonium chloride,

Benzyltributylammonium chloride,

Triethylamine,

Tripropylamine,

Tributylamine,

Triheylamine,

Benzyldimethylamine.

The amount of catalyst can vary within wide limits. In general, 0.1 to 10 wt .-%, preferably 0.3 to 6 wt .-%, based on the weight of the compounds of general formula VI used.

Sodium hydroxide or potassium hydroxide solution is preferably used as the base. The preferred procedure is as follows:

Compounds of the general formula V are introduced and then one to 1.2 equivalents of the aqueous base are added dropwise at temperatures between −20 ° C. and 50 ° C., preferably 0-30 ° C. The concentration of the base does not matter, but it is advisable not to work too diluted and to use about 25-50% solutions of the bases. The base should be added as slowly as possible.

The course of the reaction is followed by measuring the pH.

When a pH of 7-8 is reached, the catalyst is added and a further 1-1.2 equivalents of an aqueous base. The concentration of the aqueous base used should be between 1 and 50%, preferably between 5 and 25%.

The reaction is preferably carried out at elevated temperature, usually between 50 and 100 ° C., preferably between 80 and 100 ° C.

The end of the reaction is expediently determined by checking the pH. When it has approximately reached the neutral point, it is allowed to cool and, after the organic phase has been separated off, it is purified by distillation.

Some of the compounds of the general formula VI are known. New and known compounds of the general formula VI

MR'

I I

HahC-CHz-C - C-R2 VI

I I

Shark OH

in which

Hai, R1, R2 can have the meaning given above

5

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15

20th

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35

40

45

50

55

60

65

636095

can be obtained by using a compound of general formula VII

CH2 = CH

/ R '

-C-R2

\

VII

■ ox in which

X represents hydrogen or the radical O

II

-C-R3 stands and

R1, R2, R3 have the meaning given above, with a carbon tetrahalide of the general formula VIII,

CHaU

VIII

The following compounds of the general formula VIII are preferably used:

CCU, CBr4, CChBr, CFzBn, CFBn, CClBn, CCbF.

s

The reaction can be carried out in the absence or, preferably, in the presence of a solvent. Excess carbon tetrahalide is preferably used as the solvent, or hydrocarbons such as toluene, for example. Acetonitrile is particularly preferably used. The use of alcohols, for example propanol, butanol or pentanol, is also preferred. The reaction is usually carried out at temperatures of about 50-150 ° C, optionally under pressure. 15 The latter process is preferably carried out using suitable catalysts. For example, the following are possible:

in which

Shark has the meaning given above.

If 3-methyl-butenol (3) and carbon tetrachloride are used as starting materials, the course of the reaction can be represented by the following formula:

CHa CHs

I I

CH- = CH-C-CHj + CCU -> CCI3-ch2-CHCI-C-CH3

I I

OH OH

The starting materials which can be used in this process are defined by the general formulas VII and VIII. You are known. The following compounds of the general formula VII are preferably used:

25th

30th

35

1. Substances that form free radicals, such as benzoyl peroxide, acetyl peroxide, di-tert-butyl peroxide, tert-butyl hydroperoxide and azobisisobutyronitrile. In general, catalytic amounts of the radical generator are sufficient, but even larger amounts are not harmful.

2. Metal salts in the presence of organic amines. Examples of suitable metal salts are copper and iron salts, such as copper (I) chloride, copper (II) chloride, iron (II) sulfate, iron (III) chloride. Examples of suitable amines are pyrrolidine, piperidine, n-butylamine, cyclohexylamine, triethylamine and dimethylamine. They can also be used in the form of their salts, for example the hydrochlorides. Catalytic amounts of the catalysts are also sufficient for the reaction. Larger quantities accelerate the reaction.

3. The reaction can also be carried out by irradiation with UV light or y-rays.

Isoprene alcohol (3-methyl-1-buten-3-ol), allyl alcohol. As already mentioned, the

l-buten-3-ol, l-penten-3-ol, 3-methyl-l-penten-3-ol, baren dihalogenvinyl-y-butyrolactones of the general

3-ethyl-1-penten-3-ol, 1-vinyl-cyclopentan-1-ol, formula I as intermediates for the production of insecticides

1 - vinyl-cyclohexan-1-ol and its esters, such as 40 active ingredients. The production of these active ingredients can be done through the acetates.

the following formula scheme is illustrated:

C00C2H5

OOC2H5

CH3-lj: 1 COOC2H5

/ \ à

CH, CH.

CH.

Clx_

cV

CH,

'2H5

+

Q "T.

<^> - ch2oh - * •

CI-CI

CH-

CH3CH3

636095

The 2,2-dimethyl-3 (2 ', 2'-dichlorovinyl) cyclo-propanecarboxylic acid m-phenoxybenzyl ester obtained in this way is a known insecticidal active ingredient (see German Offenlegungsschrift 2,326,077).

The following examples illustrate the method according to the invention without restricting the breadth of its applicability:

Representation of y-butyrolactone example 1

11.5 g of sodium are dissolved in 250 ml of ethanol, 80 g of diethyl malonate are added dropwise at room temperature and then 128 g of 2,2-dimethyl-3 (2 ', 2'-dibromovinyl) oxirane at 30-35 ° C. in the course of one hour . Then hold for 4 hours at 35 ° C.

To saponify the resulting 4-methyl-3- (2 ', 2'-dibromovinyl) -y-valerolactone-2-carboxylic acid ethyl ester, 800 ml of 10% sodium hydroxide solution are added to the reaction solution and the mixture is stirred for 12 hours at room temperature. Ethanol is distilled off and the reaction solution is acidified to pH 1 with concentrated hydrochloric acid. 4-Methyl-3- (2 ', 2'-dibromovinyl) -y-valerolactone-2-carboxylic acid precipitates, mp 140 ° C. This is filtered off and suspended in o-dichlorobenzene and heated to 170-180 ° C. for 2 hours with stirring. After cooling, 91 g (61% of theory) of 4-methyl-3- (2 ', 2'-dibromovinyl) -y-valerolactone crystallize from mp 115 ° C.

Preparation of an Intermediate Example 2

11.5 g of sodium are dissolved in 250 ml of ethanol, 80 g of diethyl malonate are added dropwise at room temperature and then 83.5 g of 2,2-dimethyl-3- (2 ', 2'-dichlorovinyl) at 40 ° C. in the course of one hour. oxirane. Then hold for a further 3 hours at 40 ° C and then add 800 g of 10% sodium hydroxide solution.

Then it is heated to boiling for 2-3 hours, the ethanol is distilled off and the mixture is concentrated. Hydrochloric acid to pH 1. After filtering off, 4-methyl-3- (2 ', 2'-dichlorovinyl) -y-valero-lactone-2-carboxylic acid is obtained, which melts at 138 ° C. after drying.

Preparation of oxirane Example 3

195 g of 45% sodium hydroxide solution are added dropwise at room temperature to a mixture of 480 g of l, l-dimethyl-2,4,4,4-tetra-chlorobutanol and 10 ml of triethylamine. The mixture is stirred for 3 hours at room temperature, then 3000 ml of water, 20 g of tetrabutylammonium chloride and 112 g of potassium hydroxide are added and the mixture is heated to boiling for 8 hours. After cooling, the organic phase is separated off, the aqueous phase is extracted with methylene chloride and the combined organic phases are fractionated in vacuo. 294 g (88% of theory) of 2,2-dimethyl-3- (2 ', 2'-dichlorovinyl) oxirane with a bp = 63-65 ° / 15 mm are obtained. ng, = 1.4752.

Example 4

195 g of 45% sodium hydroxide solution are added dropwise at room temperature to a mixture of 480 g of l, l-dimethyl-2,4,4,4-tetra-chlorobutanol and 10 ml of tributylamine. The mixture is stirred for 3 h at room temperature, then 3000 ml of water, 20 ml of tributylamine and 112 g of potassium hydroxide are added and the mixture is heated to boiling for 12 h. After cooling, the organic phase is separated off, the aqueous phase is extracted with methylene chloride and the combined organic phases are fractionated in vacuo. 274 g (82% of theory) of 2,2-dimethyl-3- (2 ', 2'-dichlorovinyl) oxirane with a bp = 62-63 ° / 14 mm are obtained.

Example 5

195 g of 45% sodium hydroxide solution are added dropwise to a mixture of 480 g of l, l-dimethyl-2,4,4,4-tetra-chlorobutanol and 10 ml of triethylamine at room temperature in the course of 2 hours. The mixture is stirred for 5 hours at room temperature, the sodium chloride which has separated out is brought into solution with water and is neutralized. The organic phase is separated off, the aqueous phase is extracted with methylene chloride and the combined organic phases are fractionated in vacuo. 381 g (94% of theory) of 2,2-dimethyl-3 - ((2 ', 2', 2 '-trichloroethyl) -oxirane with a bp = 82-84V13 mm. N? 0 = 1.4690.

b) 203.5 g of 2,2-dimethyl-3- (2 ', 2', 2'-trichloroethyl) oxirane, 1500 ml of water, 56 g of potassium hydroxide and 10 g of tetrabutylammonium bromide are heated to boiling for 10 hours with stirring . After cooling, the organic phase is separated off, the aqueous phase is extracted with methylene chloride and the combined organic phases are fractionated in vacuo. 144 g (86% of theory) of 2,2-dimethyl-3- (2 ', 2'-dichlorovinyl) oxirane of bp = 68 ° / 17 mm are obtained.

Representation of the compounds of formula IV

Example 6

430 g (5 mol) of 3-methyl-1-buten-3-ol, 2500 ml of carbon tetrachloride and 40 g of water-containing benzoyl peroxide are boiled for 10 hours on a water separator. After adding another 40 g of moist benzoyl peroxide, boil again on the water separator for 10 hours. After cooling, it is washed with cold NaOH in order to remove the benzoic acid formed. The solvent is then distilled off. The remaining residue is distilled on the oil pump. 971 g (81% of theory) of l, l-dimethyl-2,4,4,4-tetrachlorobutanol with a bp = 75-85 ° C./0.1 mm are obtained. The structure was confirmed by IR and NMR spectra. n2o = 1.4975.

Example 7

120 g of l, l-dimethyl-2-propenyl acetate, 332 g of carbon tetrabromide, 16 gn-butylamine and 14 g of iron (III) chloride (hexahydrate) in 220 g of acetonitrile are heated at 100 ° C. for 12 hours. After cooling, the mixture is filtered off, the solvent is distilled off and 168 g of potassium hydroxide in 2000 ml of water are added dropwise to the residue at room temperature. Then 20 g of tetrabutylammonium chloride are added and the mixture is heated at 80 ° C. for 1 hour, is neutralized after cooling and extracted with methylene chloride. Then it is fractionally distilled. 159 g (62% of theory) of 2,2-dimethyl-3- (2 ', 2'-dibromovinyl) oxirane of bp = 86-88 ° C./15 mm are obtained. n2D0- = 1.5332. NMR (in CDCh): 8 (ppm) = 1.3-1.4 (d, 6 protons), 3.25 and 3.4 (d, 1 P); 6.2 and 6.35 (d, 1 P).

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Claims (2)

636095 2nd PATENT CLAIMS 1. Process for the preparation of dihalogenvinyl-y-buty-rolactones of the general formula I Shark shark R = o in which Hai represents the same or different F, CI or Br residues, R1 and R2 stands for identical or different radicals of the group hydrogen or Ci-4 alkyl or together with the adjacent carbon atom form a cycloaliphatic ring with up to 7 carbon atoms, characterized in that an oxirane of the general formula IV Shark Shark > JR R 2 XV in which Hai, R1, R2 have the meaning given above, with malonic esters of the general formula V ch2- -COOR3 -COOR3 in which R3 represents C1-C4-alkyl, is reacted in the presence of a base and the reaction mixture is heated without isolation of intermediates. 2. The method according to claim 1, characterized in that the reaction takes place in the presence of a diluent. (2 ', 2'-dichlorovinyl) -y-valerolactone is formed as a by-product in the saponification of 2,2'-dimethyl-3- (2', 2'-dichlorovinyl) cyclo-propane-1-carboxylic acid (see Pestic 1974 (5) pages 792-793). 5 In addition, a process for the production of 4- (2'-2 '-dihalogenvinyl) -3,3-dimethyl-y-butyrolactones has become known (see German Offenlegungsschrift 2,623,777). However, the process described there can only be carried out economically starting from 10 dimedone and, moreover, does not lead to the desired 3-dihalovinyl-y-butyl-rolactones. The process according to the invention for the preparation of partially known dihalogenvinyl-y-butyrolactones of the general formula I