Stereocontrolled access to enantiopure to enantiopure 7-substituted cis- and trans-octahydroindoles

Cyclocondensation of (R)-phenylglycinol with stereoisomeric mixtures (racemates, cis/trans) of 3-substituted 2- oxocyclohexaneacetates stereoselectively afforded tricyclic oxazoloindolone lactams, from which straightforward procedures for the stereocontrolled formation of enantiopure 7-substituted octahydroindoles with a variety of stereochemical patterns have been developed. The methodology has been successfully applied to the synthesis of (+)-α-lycorane.