Insecticides

Abstract

New insecticides are of formula: ##STR1## wherein R.sup.1 represents hydrogen or a methyl group; R.sup.2 represents hydrogen or a halogeno or lower alkyl group; R.sup.3 represents hydrogen or a halogeno, lower alkyl (which is different to R.sup.2 when R.sup.2 represents a lower alkyl group) or carbo(loweralkoxy) group which contains at least 2 carbon atoms in the lower alkoxy residue when R.sup.2 represents methyl or R.sup.2 and R.sup.3 together with the carbon atom to which they are attached represent a cycloalkylene ring having at least one endocyclic carbon to carbon double bond; with the proviso that (a) R.sup.2 and R.sup.3 each represent hydrogen only when R.sup.1 represents methyl and (b) R.sup.3 contains at least 2 carbon atoms when R.sup.1 and R.sup.2 each represent hydrogen; and R represents a group which form insecticidal esters with chrysanthemic acid e.g. 5-benzyl-3-furylmethyl, 3-phenoxybenzyl, .alpha.-cyano-3-phenoxybenzyl. The esters are prepared by forming the ester linkage conventionally or by a Wittig reaction using a 3-formyl- or 3-acetyl-2,2-dimethyl cyclopropane carboxylic acid esterified with the desired residue or by an alkyl group which is subsequently converted to the desired residue.

Dependencies are inferred from the claim text.