EFFICIENT STEREOSELECTIVE SYNTHESIS OF BOTH (+/-)-JUVABIONE AND (+/-)-EPI-JUVABIONE BY NEW EXTRACYCLIC STEREOCONTROL METHODOLOGY

Article abstract of DOI:10.1016/S0040-4039(00)95158-X

The Hosomi-Sakurai reactions of E- and Z-crotylsilanes with cyclohexenone at -78 degC showed respectively high erythro and relatively low threo selectivities, modification of the silyl substituents giving a variable effect.In the reaction with Z-alkoxycrotylsilanes, the threo selectivity could be improved by the utilization of the kinetic difference between the diastereomeric products 4 and 5 to the secondary cyclization.Starting from 4 and 5 thus obtained, the syntheses of both (+/-)-juvabione and (+/-)-epi-juvabione have been respectively achieved in a concise way.