STEREOSELECTIVE TOTAL SYNTHESIS OF RACEMIC STACHENONE

The C/D ring synthon bicyclo[3.2.1]octenedione (4), available from acid-catalyzed rearrangement of the bicyclo[2.2.2]octenol (7), was converted into the trans-fused B-C/D tricyclic derivative 5 by aldol cyclization and dissolving metal reduction and then into trans-anti-trans tetracyclic diterpene stachenone (1) by Robinson ring annelation and reductive alkylation in an overall yield of 16% from the starting bicyclo[2.2.2]octenone (3). © 1979, American Chemical Society. All rights reserved.