Abstract: Disclosed is a process for producing an optically active amine represented by the formula (IV) ##STR1## wherein R.sub.7 and R.sub.8 each denote an alkyl group, aryl group or aralkyl group, providing that they do not denote the same group at the same time, and * indicates an asymmetric carbon atom, which comprises reacting an asymmetric reducing agent obtained from (1) an optically active amine derivative represented by the formula (I) ##STR2## wherein R.sub.1 denotes an alkyl group, aryl group or aralkyl group; R.sub.2 denotes a hydrogen atom, alkyl group or aralkyl group; R.sub.3 denotes an aryl group or a substituent represented by the formula (II) ##STR3## wherein R.sub.4 and R.sub.5 each denote a hydrogen atom, aryl group or aralkyl group, and * is as defined above, (2) a metal borohydride and (3) sulfuric acid, with either the syn-isomer or the anti-isomer of an oxime derivative represented by the formula (III) or with a mixture rich in either one of the two isomers ##STR4## wherein R.sub.

Abstract: Racemic dihalovinylcyclopropane carboxylic acid halides, which are intermediates of such insecticides as permethrin, cypermethrin etc., are prepared by allowing phosphorus iodides, silicon iodides or boron iodides to react with optically active dihalovinylcyclopropane carboxylic acid halides of the formula: ##STR1## wherein X and Y stand for halogen atoms and the mark * indicates an asymmetric carbon atom.

Abstract: Trans-2,2-dimethyl-3-(2,2-dihalovinyl)-cyclopropane carboxylic acid esters which are intermediate of insecticides are prepared by allowing (1) alkali metal alkoxides and titanium alkoxides or (2) silicon iodides to react with cis- or cis-/trans-mixed 2,2-dimethyl-3-(2,2-dihalovinyl)-cyclopropane carboxylic acid esters of the formula ##STR1## wherein X is a halogen atom and R is an alkyl, cycloalkyl or aralkyl group having 1-10 carbon atoms.