Enantiospecific Formal Total Synthesis of (+)-Fawcettimine

The diastereospecific attack of the silyl enol ether on the activated cyclopropyl diester 27 generated the hydrindanone 28 with complete stereocontrol. Thermal decarbomethoxylation of 28 gave the monoester 29, a key intermediate in Heathcock’s synthesis, thereby completing a formal total synthesis of (+)-fawcettimine 1. The analogous cyclization of 33, the diastereomer of 27, afforded the diastereomeric diester 34, thereby demonstrating that the cyclization process is diastereospecific.