Iminyl radical initiated sulfonylation of alkenes with rongalite under photoredox conditions

Abstract

A photoredox-catalyzed reaction of oximes, rongalite and electrophiles is accomplished under mild conditions, which affords diverse pyrrole-substituted aliphatic sulfones or sulfonamides in moderate to good yields. This photoinduced sulfonylation with rongalite occurs efficiently with good functional group compatibility and excellent regioselectivity. During the reaction process, the sulfinate generated in situ can be trapped by various electrophiles. A plausible mechanism is proposed, involving photoinduced iminyl radical-mediated cyclization and sulfonylation with sulfur dioxide radical anions from rongalite.