Rhodium-Catalyzed Isomerization of Propargylic Alcohols

摘要

alpha,beta-Unsaturated carbonyl compounds are useful building blocks in organic synthesis. Therefore, there has been continued interest in their facile synthesis. In general, isomerization of propargylic alcohols to alpha,beta-enones or alpha,beta-enals are one of the most efficient methods due to the easy access to propargylic alcohols and high atom economy. However, such isomerizations have not been well examined compared with well established isomerizations of allylic alcohols. We herein present our investigation into a cationic rhodium(I) complexes-catalyzed isomerization of secondary propargylic alcohols to alpha,beta-enones and its extension to propargylic diols. In addition, some asymmetric and mechanistic aspects of the present isomerization are also discussed.