Synthesis of β-enamino malonates through caesium carbonate-promoted reaction of nitro-substituted donor–acceptor cyclopropanes

Abstract

A caesium carbonate-promoted reaction of nitro-substituted donor–acceptor cyclopropanes (DACs) with primary aromatic amines in water provides a convenient access to β-enamino malonates under mild reaction conditions. The transformation takes place through the formation of allene intermediates from the DACs followed by the conjugate addition of various primary aromatic amines to the intermediates. The reaction proceeds more efficiently in water as compared with organic solvents and the products were isolated in good yields by filtering through a silica gel column without any prior extraction procedure.