A new atom-transfer radical cyclization (ATRC) mediated by photocatalytically-generated aminyl radicals that do not have an α-C-H bond

Abstract

A photocatalytic method for the synthesis of sp3-rich bicyclic O,O- and N,O-iodoacetals from enol ethers and Boc-protected enamines has been developed. The simple procedure uses catalytic eosin (EY.Na2), a green solvent system (EtOH/water) and blue LED irradiation. The photocatalytic step involves radical cyclisation with halogen atom relocation mediated by aminyl radicals that do not have an α-C–H bond.