CYCLOPROPANE DERIVATIVES

1293857 Cyclopropane carboxylic acid esters ROCHE PRODUCTS Ltd 19 May 1971 [8 June 1970] 27581/70 Heading C2C The invention comprises cyclopropane carboxylic acid esters of the general formula in which R is hydrogen or chlorine or a C 1 -C 4 alkyl group. They may be prepared by either reacting 2,2,3,3-tetramethylcyclopropane carboxylic acid chloride or bromide with an alcohol of the general formula or by reacting an alkali metal salt, the silver salt or a tri-(C 1 -C 4 alkyl) amine salt of 2,2,3,3- tetramethyl-cyclopropane carboxylic acid with a halide of the general formula in which hal stands for a halogen atom; or by reacting a compound of general formula with an alkali metal salt of a phenol of the general formula The sodium salt of 2,2,3,3-tetramethyl-cyclopropane carboxylic acid used as starting material is prepared by reacting the free acid with sodium hydroxide and the acid chloride and bromide are prepared by reacting the free acid with thionyl chloride and thionyl bromide. The esters may be used as active ingredients in insecticidal compositions which may also contain compatible carriers and emulsifiers and/or surfactants.