Redox-neutral manganese-catalyzed synthesis of 1-pyrrolines.

This report describes a manganese-catalyzed radical [3 + 2] cyclization of cyclopropanols and oxime ethers, leading to valuable multi-functional 1-pyrrolines. In this redox-neutral process, the oxime ethers function as internal oxidants and H-donors. The reaction involves sequential rupture of C-C, C-H and N-O bonds and proceeds under mild conditions. This intermolecular protocol provides an efficient approach for the synthesis of structurally diverse 1-pyrrolines.