Stereo isomers of n-(r)-1-aryl-ethyl)-1-alkyl-2,2-dichlorocyclopropane carboxamide

Novel stereoisomers of N- (R) - (1-aryl-ethyl) -1-alkyl-2,2-dichloro-cyclopropanecarboxamides of the formula (Ia) and (Ib) and their mixtures, in which R¹, R² and X have the meanings given in the description, their new intermediates - the corresponding carboxylic acid esters, carboxylic acids and carboxylic acid chlorides - and the use of stereoisomers or mixtures of the compounds of the formulas (Ia) and (Ib) for combating pests. The novel compounds are generally defined by the formulas (Ia) and (Ib) and can be prepared by analogy, for example from suitable carboxylic acid chlorides with suitable amines and optionally the stereoisomer mixtures are separated.