Photocatalyzed dehydrogenation of aliphatic N- heterocycles releasing dihydrogen

We report the iridium-nickel dual photocatalytic acceptorless and redox neutral dehydrogenation of aliphatic heterocycles yielding cyclic alkenes without overoxidation at room temperature. Excitation of the iridium photocatalyst initiates the formation of a nickel hydride intermediate that yields alkenes and H2 via β-hydrogen elimination. The reaction proceeds regioselective and the scope was demonstrated by the synthesis of ten biologically relevant molecules and drugs. In addition, commercially and easily available N-heterocyclic alkane starting materials were converted by the method into functionalized alkenes of high synthetic and commercial value.