Concise syntheses of (–)-quinocarcinol methyl ester and (–)-oxa-quinocarcinol methyl ester†
Abstract
A concise synthesis of (–)-quinocarcinol methyl ester was accomplished with an overall yield of 39% through a 9-step longest linear sequence (LLS). Our synthesis features a two-step ester reduction/reductive amination sequence, a stereoselective [3 + 2] intramolecular cross-cycloaddition for the construction of bicyclo[3.2.1]octane skeletons, four simultaneous hydrogenolysis reactions in a one-pot process, and a stereoselective Krapcho decarboxylation. By following this protocol, (–)-oxa-quinocarcinol methyl ester was also achieved.