Lewis Acid‐Catalyzed [3+2] Cycloaddition of Donor‐Acceptor Cyclopropanes and Enamines: Enantioselective Synthesis of Nitrogen‐Functionalized Cyclopentane Derivatives

Abstract

AbstractA straightforward and efficient method for the synthesis of nitrogen‐functionalized cyclopentane derivatives via [3+2] cycloaddition of enamines with donor‐acceptor cyclopropanes in the presence of catalytic amounts of various Lewis acids at room temperature has been developed; furthermore, the corresponding β‐amino acid was synthesized by monodecarboxylation and hydrogenolysis. An enantioenriched synthesis of nitrogen‐functionalized cyclopentane derivatives through dynamic kinetic asymmetric transformation of racemic donor‐acceptor cyclopropanes has also been achieved employing a copper complex [Cu(OTf)2‐L1] as the catalyst affording an enantiomeric ratio up to 8:1.magnified image