DE2812365A1 - METHOD FOR THE PRODUCTION OF ESTERS OF M-PHENOXYBENZYL ALCOHOL AND OF ALPHA-CYANO- AND ALPHA-AETHINYL DERIVATIVES THEREOF WITH CARBONIC ACIDS - Google Patents

Description

PATENT ADVOCATE TDR. RICHARD KNEISSL Widenmsyerstr. 46

D-8000 MUNICH 22 Tel. 089/295125

Folder 24415

2812365 21. Harz 1978

IMPERIAL CHEMICAL INDUSTRIES LTD. London, UK

Process for the preparation of esters of m-phenoxybenzyl alcohol and of QC-cyano- and -äthiny! Derivatives thereof with carboxylic acids

Priority: 4/15/77 - Great Britain

809843/0622

DESCRIPTION:

The invention relates to an improved process for the preparation of esters of m-phenoxybenzyl alcohol.

A number of esters of m-phenoxybenzyl alcohol are of value as insecticides, such as those with certain sub-. substituted 2,2-dimethylcyclopropanecarboxylic acids. The esters can be prepared from the corresponding acids by converting the latter into the acid chloride, which can then be reacted with m-phenoxybenzyl alcohol. The cyclopropanecarboxylic acids are expediently in the form of their Methyl and ethyl esters isolated. The latter allow an alternative route to the corresponding m-phenoxybenzyl esters, which expediently from the methyl or ethyl esters by an ester exchange reaction with m-phenoxybenzyl alcohol or certain derivatives thereof can be obtained in the presence of an ester interchange catalyst.

GB-PA 15581/76 describes the use of sodium methoxide or sodium ethoxide as a transesterification catalyst in the conversion of methyl or ethyl esters of carboxylic acids into their esters with m-phenoxybenzyl alcohol or the a-cyano or ° t - ethynyl derivative thereof. These sodium alkoxides are effective catalysts. However, if esters of cyclopropanecarboxylic acids of the pyrethrin type play a role, then the cis / trans isomer ratio can go in the direction of of the less insecticidally active trans isomer.

In GB-PA 15582/76 is the use of tetramethyl or tetraethyl titanate as a transesterification catalyst in the Conversion of the methyl or ethyl esters of carboxylic acids into their esters with m-phenoxybenzyl alcohol or the a-cyano or (X-ethynyl derivative thereof. These tetraalkyl titanates are also effective esterification catalysts

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and do not affect the cis / trans isomer ratio of the Esters of cyclopropanecarboxylic acids of the pyrethrin type. However the tetraalkyl titanates are very reactive towards water. For this reason, their quality is very variable, and it depends on whether they are freshly made whether or not and to what extent they have been sealed off from contact with moisture. Catalyst - v Their poor quality can adversely affect the ester interchange reaction, leading to the formation of by-products lead, which leads to a reduction in the purity and the yield of the desired esters.

According to the invention a process for the preparation of esters of m-phenoxybenzyl alcohol or its CL- cyano and & -Äthinylderivaten _m will now proposed it carboxylic acids, which is carried out by reacting a methyl or ethyl ester of carboxylic acid, m-phenoxybenzyl alcohol or a CX Cyano- or oi-ethynyl derivative thereof and an ester interchange catalyst which is a diol or polyol titanate or a chelate compound of titanium with a * diketone or a ß-ketoester, with any residual valences on the titanium atom by a diol, a polyol , OK or OR (R = a lower alkyl group) are saturated, and the mixture is heated to a temperature such that methanol or ethanol are removed by distillation during their formation.

Diol titanates are obtained by reacting tetraalkyl titanate, Ti (OR)., Where R is a lower alkyl group, with, for example, one or two moles of a diol, a compound of the formula Ti (DiOl) (OR) ₂ or Ti (DiOl) _{2 being} obtained . Compounds of the formula Ti (Diol) (OR) 2 can be reacted further with water, whereby compounds of the formula Ti (Diol) (OH) ₂ or compounds with the condensed structures / Ti (DiOl) OJ ⁷ , where η is an integer, which are also used as catalysts within the field of

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finding fall, be preserved.

The reaction of a tetraalkyl titanate with, for example, a polyol gives a polyol titanate of indeterminate, possibly polymeric structure, but which is an effective catalyst within the scope of the invention.

The chelate compounds of titanium which can be used as catalysts are obtained by reacting a tetraalkyl titanate, Ti (OR), where R is a lower alkyl group, with a diketone such as acetylacetone or with a β-keto ester such as ethyl acetoacetate , whereby compounds of the formula Ti (chelate) ₂ (OR) ₂ are obtained. The latter can be reacted further with a diol, whereby Ti (chelate) ₂ (diol) is obtained, or with water, whereby Ti (chelate) ₉ (OH) _ or compounds with the condensed structure / Ti (chelate) “O /, where η is an integer, which are also catalysts within the scope of the invention.

Examples of diols and polyols used in the manufacture the titanium-based catalysts for the inventive Processes that can be used are ethylene glycol, Propane-1,2-diol, propane-1,3-diol, butane-1,2-diol, butane-1,3-diol, Butane-2; 3-diol, butane-1,4-diol, 2-ethylhexane-1,3-diol, Neopentyl glycol, hexane-1,6-diol, pinacol, glycerine, Pentaerythritol and secondary cellulose acetate.

Particularly preferred catalysts are those of the formula Ti (diol) (OH) _2,. wherein the diol is an unbranched α, ω-diol, since these catalysts are generally insoluble in the reaction mixture and can therefore easily be separated off and recycled.

The term "lower alkyl" in this specification refers to alkyl groups having 1 to 4 carbon atoms.

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The reactants of the process can be in any order are mixed, whereupon the mixture, which is preferably agitated or otherwise agitated, to reaction temperature is brought. The preferred reaction temperatures are between 80 and 200 C. Temperatures outside this range can be used, but lower temperatures may require longer reaction times. Higher temperatures and higher temperatures pose a risk of decomposition of the product.

If necessary, a solvent can also be used, in particular one which results in a reaction mixture that at. the desired reaction temperature boils, so that the methanol formed during the process or Ethanol distilled off with part of the solvent.

Suitable solvents are, for example, halogenated hydrocarbons such as toluene or methylcyclohexane Hydrocarbons in which the halogen is inert under the reaction conditions, such as chlorinated aromatic hydrocarbons, for example chlorobenzene, and ethers, such as dioxane. Low boiling solvents, e.g. Cyclohexane, can be used, but require longer reaction times at atmospheric pressure.

Many of the catalysts for use within the scope of the present invention are against moisture not sensitive, which is why it is not necessary in such cases that the reactants used or the possibly used Solvents are particularly dry. This applies in particular to catalysts that are free from groups of the formula -OR are. This is a particular advantage of using this particular group of catalysts.

The amount of catalyst is at least 0.0005 mol and is preferably between 0.001-0.2 mol per mol of carboxylic acid ester.

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The required amounts of m-phenoxybenzyl alcohol or its α-cyano or α-ethynyl derivative and the methyl or ethyl ester of the carboxylic acid are equimolar. If necessary .. can be an excess one of the reactants can be used, with the unreacted excess being recovered at the end of the process can be, for example, by distillation under reduced pressure. * ■

The ester formed by the process of the invention can be isolated by any convenient method, for example by using an optionally present solvent and any unaltered reactant present, removed by distillation, so that the raw ester remains, which is then purified by conventional means which are suitable for the ester in question can be.

The methyl or ethyl ester of a carboxylic acid which can be used in the process according to the invention is any such ester which has a significantly higher boiling point than the reaction temperature. Such esters can be derived from aliphatic, aromatic, cycloaliphatic or heterocyclic carboxylic acids, but the process according to the invention is of particular value for the preparation of m-phenoxybenzyl and Qi-cyano and ct-ethynyl-m-phenoxybenzyl esters with insecticidal activity, which are for example, ^a 4-methyl--isopropylphenylessigsäure derived, or, in particular esters of 2,2-Dimethylcyclopropancarbonsäuren the Pyrethrintype.

Examples are in particular the esters of 2,2-dimethylcyclopropanecarboxylic acids, which contain phenyl groups substituted in the 3-position, such as 2 ', 2'-dimethylvinyl-, 2 ', 2 · -dichlorovinyl-, 2' -ethylvinyl- and 2 ', 2' -dibromovinyl ^ · groups. These acids are normally obtained as mixtures of cis and trans forms, which in the case of the desired

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- Q -

ten m-phenoxybenzyl ester is a different insecticidal Have activity. The inventive method is insofar of particular value since there is little conversion of the cis forms into the less effective trans forms and fewer by-products are formed. The method also has the advantage that it is generally a greater conversion of the methyl or ethyl esters into Esters of cyclopropanecarboxylic acids of the pyrethrin type in relation to the comparable processes in which the catalyst consists of tetramethyl or tetraethyl titanate, sodium methoxide or sodium ethoxide.

The preparation of typical catalysts for use in the process according to the invention is described below:

Catalyst production A

A solution of 28.4 parts of isopropyl titanate in 50 parts Petroleum ether with a boiling point of 100-120 ° C. was treated with 7.6 parts of propane-1,3-diol. The reaction was slightly exothermic, and the temperature was kept at 40 ° C. by external cooling. After stirring the mixture for 2 hours the solvent removed by vacuum evaporation, wherein 24 parts of a yellow oil remained.

Catalyst manufacture B

A solution of 28.4 parts of isopropyl titanate in 50 parts of petroleum ether with a boiling point of 100-120 ° C. was 7.6 parts Treated propane-1,3-diol. The reaction was slightly exothermic, and the temperature was kept at 40 ° C. by external cooling. After stirring the mixture for 2 hours 80 parts of water were added with rapid stirring. A precipitate formed. The mixture was another hour stirred and then filtered to obtain the product

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-JO-de, which after washing with petroleum ether and drying from 14.7 Parts of a white powder consisted.

Catalyst manufacture C

Catalyst preparation B was repeated, except that the 7.6 parts of propane-1,3-diol by 9 parts of butane-2,3-diol> have been replaced. 15.0 parts of product were obtained.

Catalyst manufacture D

Catalyst preparation B was repeated except that 7.6 parts of propane-1,3-diol were replaced by 7.6 parts of propane-1,2-diol have been replaced. 12.1 parts of product were obtained.

Catalyst production E

Catalyst preparation B was repeated except that the 7.6 parts of propane-1,3-diol by 6.2 parts of ethylene glycol have been replaced. 13.3 parts of product were obtained.

Catalyst production F

Catalyst Preparation B was repeated except that the 7.6 parts of propane-1,3-diol were replaced with 9.0 parts of butane-1,4-diol . 11.6 parts of product were obtained.

Catalyst production G

Catalyst Preparation B was repeated except that the 7.6 parts of propane-1,3-diol were replaced with 11.8 parts of pinacol became. 14.6 parts of product were obtained.

Catalyst production H

Catalyst preparation B was repeated except that the 7.6 parts of propane-1,3-diol were replaced by 11.8 parts of hexane- 1,6-diol

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have been replaced. 13.4 parts of product were obtained. Catalyst production I

Catalyst Preparation -B was repeated except that the 7.6 parts of propane-1,3-diol were replaced by 10.4 parts of neopentyl glycol. 15 parts of product were obtained. *.

Catalyst manufacture J

A solution of 34.1 parts of isopropyl titanate in 50 parts of petroleum ether with a boiling point of 100-120 ° C. was 17.5 parts Treated 2-ethylhexane-1,3-diol in 50 parts of petroleum ether. The temperature of the exothermic reaction was determined by external Cooling kept at 40 ° C. The mixture was stirred for an additional 2 hours and then 100 parts of water were added with rapid stirring admitted. After stirring the mixture for 30 minutes and allowing the mixture to settle, the petroleum ether became the layer separated, dried and evaporated to give 19.6 parts of a white solid product.

Catalyst production K

A solution was added to a solution of 28.4 parts of isopropyl titanate in 40 parts of petroleum ether with a boiling point of 100-120.degree of 10.4 parts of neopentyl glycol in 40 parts of 1,4-dioxane were added. The mixture was kept at 40 ° C. for 1 hour, with Treated parts of water at 35 C, stirred for 1 st and refluxed and finally filtered, with 16 parts of one white granular product.

Catalyst production L

A solution of 42.6 parts of isopropyl titanate in 50 parts of dry 1,4-dioxane was mixed with a solution of 9.2 parts Treated glycerin in 20 parts of dry 1,4-dioxane. That

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The mixture was stirred for 4 hours, treated with 25 parts of water, stirred for a further hour and finally filtered. Of the The residue was washed with water and dried to give 19.7 parts of a pale yellow solid.

Catalyst production M

A solution of 56.8 parts of isopropyl titanate in 50 parts of dry 1,4-dioxane was mixed with a solution of 12.6 parts Treated pentaerythritol in 2O parts of dry 1,4-dioxane. The mixture was stirred for 4 hours, treated with 25 parts of water, Stirred for another hour and filtered. The residue was washed with water and dried, leaving 18.4 Portions of a pale yellow product were obtained.

Catalyst production N

A solution of 10.0 parts of isopropyl titanate in 50 parts of dry 1,4-dioxane was mixed with a solution of 10.0 parts Cellulose acetate treated in 20 parts of dry 1,4-dioxane. The mixture was stirred for 4 hours, treated with 25 parts of water, Stirred for another hour and then filtered. The residue was washed with water and dried, whereby 12.7 parts of a yellow product were obtained.

Catalyst manufacture 0

A solution of 28.4 parts of isopropyl titanate in 50 parts of petroleum ether with a boiling point of 100-120 ° C. was mixed with 20 parts Acetylacetone treated in 50 parts of petroleum ether. The mixture, which its color during the addition of acetylacetone changed from colorless to red, was stirred for 2 st and then evaporated in vacuo, whereby 32.0 parts of a deep red Oil remained.

Catalyst production P

The catalyst preparation was repeated except that

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the 20 parts of acetylacetone were replaced by 36.6 parts of ethyl acetoacetate. 40.1 parts of an orange oil were obtained .

Catalyst production Q

A solution of 28.4 parts of isopropyl titanate in 50 parts - '. Petroleum ether with a bp of 100-120 ° C was with 26 parts Treated ethyl acetoacetate in 50 parts of petroleum ether. After stirring for 2 hours, the mixture became 80 parts Treated water, stirred for 1 st and finally filtered to collect the product, which is then washed with water and dried. 12.5 parts of a pale yellow solid were obtained.

Catalyst production R

The catalyst preparation Q was repeated except that the 26 parts of ethyl acetoacetate were replaced by 20 parts of acetylacetone have been replaced. 10.2 parts of a pale yellow solid were obtained.

Catalyst production S

A solution of 28 ", 4 parts of isopropyl titanate in 50 parts Petroleum ether with a boiling point of 100-120 ° C. was treated with 20 parts of acetylacetone in 50 parts of petroleum ether, and the mixture was stirred for 2 hours. 7.6 parts of propane-1,3-diol were added added dropwise and the mixture was refluxed for 1 hour. The solvent was then evaporated in vacuo, leaving 32.1 parts of a red oil.

Catalyst manufacture T

The catalyst preparation S was repeated except that the 20 parts of acetylacetone by 26 parts of ethyl acetoacetate

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2812385

were set. 37.4 parts of an orange oil were obtained.

Catalyst production ü

The catalyst preparation S was repeated except that the 7.6 parts of propane-1,3-diol were replaced by 6.2 parts kol Äthylengly- ^. 21 parts of a fine, almost white powder were obtained.

Catalyst production V

Catalyst preparation S was repeated except that the 7.6 parts of propane-1,3-diol were replaced by 11.6 parts of cyclohexane-1,4-diol have been replaced. 35 parts of a deep red solid were obtained.

Catalyst production W

Catalyst preparation S was repeated except that the 7.6 parts of propane-1,3-diol were replaced by 14.6 parts of 2-ethylhexane-1,3-diol have been replaced. 36 parts of a red oil were obtained.

Catalyst manufacture X

A solution of 28.4 parts of isopropyl titanate in 50 parts of petroleum ether with a boiling point of 100-120 ° C. was 15.2 parts Treated propane-1,3-diol. The stirred mixture was then refluxed for 1 hour and cooled, and that suspended Solid product was filtered off, washed with petroleum ether and dried, leaving 16.3 parts of a white powder were obtained.

The invention is illustrated in more detail by the following examples.

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example 1

A mixture of 42.1 parts of m-phenoxybenzyl alcohol (concentration 95%), 49.9 parts of 2,2-dimethyl-3- (2 ', 2'-dichlorovinyl) ethyl cyclopropanecarboxylate (cis / trans ratio 40:60, concentration 95%) and 2.5 parts of the propanediol titanate catalyst B was stirred at 170C, where - :. a moderate stream of nitrogen was maintained to reduce the To remove ethanol that evolved during the reaction. After 10 hours at 170 ° C., the mixture was cooled and filtered to remove the catalyst. The product was distilled under vacuum to obtain a low boiling point to remove. The remaining 71.3 parts of residue contained, according to analysis, 89.7% 2,2-Dimethy1-3- (2 ', 2'-dichlorovinyl) m-phenoxybenzyl cyclopropanecarboxylate with a cis / trans ratio of 37:63.

Example 2

The catalyst residue from Example 1 was washed with toluene and dried in vacuo at 60.degree. A preparation was carried out as in Example 1, with the recovered Catalyst was used. 72.6 parts of a product were obtained which contained 88.3% of 2,2-dimethyl-3- (2 ', 2'-dichlorovinyl) cyclopropanecarboxylic acid m-phenoxybenzyl ester with a cis / trans ratio of 38:62.

Example 3

The catalyst recovered from the preparation of Example 2 was used again in a transesterification reaction according to Example 2. There were 73.5 parts of a product obtained, the 90.4% 2,2'-dimethyl-3- (2 ', 2'-dichlorovinyl) -cyclopropanecarboxylic acid m-phenoxybenzyl ester with an cis / trans ratio of 37:63.

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Example 4

The preparation described in Example 1 was repeated using 2.5 parts of catalyst T. After lOstündigen reaction time at 170C, the mixture was cooled, treated η with 80 parts of toluene and 10 parts of 2N hydrochloric acid, heated to reflux for 30 min, cooled ^ - and filtered, and the toluene from the filtrate was removed by Vakuumabdampfung. The product was distilled to remove 8.5 parts of unreacted ethyl 2,2-dimethyl-3- (2 ', 2'-dichlorovinyl-cyclopropanecarboxylate. The 72 parts of residue contained 85% 2,2-dimethyl-3- (2 ', 2'-dichlorovinyl) cyclopropanecarboxylic acid m-phenoxybenzyl ester with a cis / trans ratio of 40:60.

Example 5

A transesterification reaction was carried out as in Example 1, 2.5 parts of the product from preparation H being used as the catalyst. After the 10 hour reaction time at 170 ° C the reaction mixture was filtered to the Remove catalyst but was not vacuum distilled to recover unreacted ethyl ester. According to an analysis, the product contained 74.0% of 2,2-dimethyl-3- (2 ', 2'-dichlorovinyl) cyclopropanecarboxylic acid m-phenoxybenzyl ester with a cis / trans ratio of 37.4: 62.6 and with 1.7% m-phenoxybenzyl alcohol. The product was subjected to distillation with superheated steam using steam at 160-180 ° C for 100 minutes. To Working up and drying the residue from the steam distillation, analysis showed that it contained 90.2% of 2,2-dimethyl-3- (2 ', 2'-dichlorovinyl) cyclopropanecarboxylic acid m-phenoxybenzyl ester with a cis / trans ratio of 37.4: 62.6 and with 0.4% m-phenoxybenzyl alcohol.

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Example 6

A mixture of 201.8 parts of m-phenoxybenzyl alcohol (99.1% concentration), 240.6 parts of 2,2-dimethyl-3- (2 ' _/ 2'-dichlorovinyl) cyclopropanecarboxylic acid ethyl ester (98.5% concentration, cis / trans ratio 38:62), 2.5 parts of catalyst J and 400 parts of o-dichlorobenzene were stirred and heated until the mixture began to distill. The distillation was carried out for 6th hours and fresh o-dichlorobenzene was periodically added to the reaction mixture to replace the volume lost by distillation. A temperature of 170 ° C. was required in the mixture at the beginning of the distillation. This was gradually increased so that a temperature of 180 ° C. was reached at the end of the reaction time.

At the end of the reaction time, the mixture was cooled to 90 ° C., whereupon 9 parts of 12% strength hydrochloric acid were added and the mixture was stirred at 90 ° C. for 20 minutes. The precipitated catalyst residue was then filtered off and the filtrate was distilled to remove the o-dichlorobenzene. The residue (381 parts) contained 89.2% of 2,2-dimethyl-3- (2 ', 2 ¹ -dichlorovinyl) cyclopropanecarboxylic acid m-phenoxybenzyl ester with a cis / trans ratio of 37:63.

Example 7

The preparation described in Example 6 was repeated except that 2.5 parts of catalyst J were replaced by 2.5 parts of catalyst R have been replaced. 388 parts of product were obtained, the 87.2% of 2,2-dimethyl-3- (2 ·, 2'-dichlorovinyl) cyclopropanecarboxylic acid m-phenoxybenzyl ester with a cis / trans ratio of 38:62.

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Example 8

The preparation described in Example 6 was repeated except that 2.5 parts of catalyst J were replaced by 2.5 parts of catalyst S were replaced. 382 parts of product were obtained, the 91.1% of 2,2-dimethyl-3- (2 ', 2'-dichlorovinyl) cyclopropanecarboxylic acid ru-phenoxybenzyl ester with an ice cream / ^. trans ratio of 38:62.

Example 9

The preparation described in Example 6 was repeated, except that the 2.5 parts of catalyst J were replaced by 2.5 parts of catalyst K. 384 parts of product were obtained which contained 91.7% of 2,2'-dimethyl-3- (2 ^I , 2'-dichlorovinyl) cyclopropanecarboxylic acid m-phenoxybenzyl ester with a cis / trans ratio of 40:60. (The ethyl ester used in this example had a cis / trans ratio of 42:58).

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Claims (10)

PATENT CLAIMS: 1. Process for the preparation of esters of m-phenoxybenzyl alcohol and of a-cyano and cx-ethynyl derivatives with Carboxylic acids, characterized in that a methyl or ethyl ester of the carboxylic acid, m-phenoxybenzyl alcohol or a tt-cyano or o <- ethynyl derivative thereof -v and mixing an ester interchange catalyst which is a diol or polyol titanate or a chelate compound of titanium with a diketone or a ß-ketoester, with any residual valences am Titanium atom are saturated by a diol, a polyol, OH or OR (R = a lower alkyl group), and the mixture heated to such a temperature that methanol or ethanol is distilled during their formation removed. 2. The method according to claim 1, characterized in that the catalyst has the formula Ti (DiOl) (OH) ₂ , wherein the diol is an unbranched α, ω-diol. 3. The method according to claim 1 or 2, characterized in that an R
is used. net that a reaction temperature between 80 and 200 C. 4. The method according to any one of claims 1 to 3, characterized in that that the reaction is carried out in a solvent. 5. The method according to claim 4, characterized in that .ein such a solvent is used that the reaction mixture ^{boils at the desired reaction temperature 1} , so that the methanol or ethanol formed during the process is distilled off with part of the solvent. 809843/0622 6. The method according to any one of claims 1 to 5, characterized in that that at least 0.0005 moles of catalyst are used per mole of methyl or ethyl ester of the carboxylic acid will. 7. The method according to claim 6, characterized in that the catalyst in an amount of 0.001 to 0.2 mol each. Mol methyl or ethyl ester of the carboxylic acid is used. 8. The method according to any one of claims 1 to 7, characterized in that that the m-phenoxybenzyl alcohol or be Ct-cyano or <* .- ethynyl derivative and the methyl or Ethyl esters of carboxylic acid can be used in equimolecular proportions. 9. The method according to any one of claims 1 to 8, characterized in that that as. Carboxylic acid is a 2,2-dimethylcyclopropane-1-carboxylic acid is used that with m-phenoxybenzyl alcohol or the cc-cyano or tf-ethynyl derivative thereof gives an ester with insecticidal activity. 10. The method according to claim 9, characterized in that the 2,2-dimethylcyclopropane-1-carboxylic acid is in the 3-position a 2 ', 2'-dimethylvinyl, 2', 2'-dichlorovinyl, Contains 2'-ethylvinyl or 2 ', 2'-dibromovinyl group. 809843/0622