Enantioselectivity of Epoxide Formation from Halohydrins by Means of Flavobacterium Rigense

Abstract
The formation of epoxides from several halohydrins was achieved using resting cells from Flavobacterium rigense. The reaction showed a high substrate specificity for halohydrins with a terminal halogen atom but only low enantioselectivity (12–58% e.e.). The epoxides always had the (S)-configuration. Substrates which in the halogen atom was replaced by another leaving group (-O-SO2CH3, -O-Tos, -N3) were not accepted. An attempt to improve the enantioselectivity by using a two phase system consisting of an aqueous and an organic solvent phase was not successful.