Synthesis of oxa-bridged carbocycles via rhodium/Lewis acid catalyzed [3 + 3] and [4 + 3] cycloadditions of carbonyl ylides with donor–acceptor strained carbocycles†

Abstract

A method for cooperative rhodium/Lewis acid-catalyzed [3 + 3] and [4 + 3] cycloadditions of carbonyl ylides with donor–acceptor (D–A) strained carbocycles is described. It affords access to a wide range of structurally diverse oxa-bridged carbocycles with high efficiency and stereoselectivity. This method operates under mild conditions, exhibits good step and atom economy, and can be extended to [3 + 2] cycloadditions with D–A 1,2-dipoles, enabling the construction of oxa-bridged spirocycles.