| Abstract: | Preparation of 3-phenoxybenzyl chrysanthemates and their dihalovinyl analogues substituted with a cyano group at the 2-, 6-, (R)-α-, or (S)-α- positions is described. The (R)- and (S)- isomers of α-cyano-3-phenoxybenzyl esters of 2,2-difluoro-, -dichloro-, and -dibromo-vinyl analogues of cis- and trans- chrysanthemic acid are separated chromatographically, as are the separate pairs of enantiomers of fenvalerate, (RS)-α- cyano-3-phenoxybenzyl (RS)-2-(4-chlorophenyl)-3-methylbutyrate. An optically active ester of α-cyano-3-phenoxybenzyl alcohol (obtained using D -oxynitrilase) with 2,2,3,3-tetramethylcyclopropanecarboxylic acid is synthesised. |
