SYNTHESIS OF EXO-7,8-EPOXYHOMOTROPANE AND ENDO-7,8-EPOXYHOMOTROPANE

Epoxidation of N-protected homotrop-7-ene (9-azabicyclo[4.2.1]non-7-en e) and 1-substituted derivatives occurs stereoselectively from the exo - (beta-) face but a practical alternative approach to the exo- epoxid es is based on a serendipitous hydride reduction of a 1-hydroxy-7 beta , 8 beta-epoxyhomotropane derivative. The epoxidation of 4-aminocycloo ct-2-enol derivatives occurs with total anti- stereoselectivity and op ens the way to endo- (alpha-) 7,8-epoxyhomotropanes. Hydride reduction or hydrogenolysis provides a range of novel 7,8-epoxy- or 7-hydroxy-h omotropanes and norhomotropanes, depending on conditions. Copyright (C ) 1996 Elsevier Science Ltd.