Diester-Substituted Aminocyclopropanes: Synthesis and Use in [3+2]-Annulation Reactions

In this Letter, we describe the synthesis of new donor-acceptor substituted cyclopropanes bearing various imido groups and their use in [3+2]-annulation reactions. A sequence of palladium-catalyzed vinylation and rhodium-catalyzed cyclopropanation gave access to the required cyclopropanes in only two steps and high overall yields. The obtained compounds were used successfully in the tin-catalyzed [3+2] annulation with enol ethers to give cyclopentylamine derivatives in 22-95% yield.