CAPILLARY GAS-CHROMATOGRAPHIC SEPARATION OF SOME DIASTEREOMERIC AMIDES FROM CARBONYLDIIMIDAZOLE-MEDIATED MICROGRAM-SCALE DERIVATIZATIONS OFTHE ACID MOIETY OF PERMETHRIN INSECTICIDE

Mixtures from microgram-scale derivatizations of reference samples of (1R,3S)-cis-, (1S,3R)-cis-, (IR,3R)-trans- and s-3-(2,2-dichloroetheny l)-2,2-dimethylcyclopropane carboxylic acid with carbonyldiimidazole a nd seven chiral amines were investigated by achiral phase capillary ga s chromatography (GC) with a flame ionization detector. The desired di astereomeric amides were identified by GC-mass spectrometry. Several c ombinations of derivatives and GC liquid phases were useful for resolv ing either pair of enantiomeric acids. Baseline separation of the four acids was achieved with (R)(-)- or (S)(+)-amphetamine derivatives and with a polar GC column of DB-WAX. The enantiomeric composition of the permethrin amides determined by GC was in agreement with the enantiom eric composition of the permethrin acids determined by polarimetry.