Photoexcited Nitroarene-Mediated Oxidation Enables the Total Synthesis of (−)-Securingine G

In general, dehydrogenation of piperideine and piperidine to pyridine requires precious transition-metal catalysts or harsh oxidative conditions. In this study, we show that photoexcited triplet-state nitroarenes act as effective dehydrogenation agents for a one-step anaerobic aromatization of these cyclic amines. The utility of this transformation is demonstrated in the second-generation total synthesis of securingine G.