A visible-light-induced cascade cyclization strategy for the synthesis of N,S-containing polycyclic compounds

Abstract

Herein, we describe an efficient and atom-economical strategy for the synthesis of N,S-containing polycyclic compounds via visible-light-induced cascade cyclization of conjugated diynes bearing two isocyano groups with disulfide. Among them, five chemical bonds and three heterocyclic rings were formed under mild conditions in one single operation through thiyl radical addition to isocyano and alkynyl groups of functionalized 1,3-diynes followed by an annulation process. In addition, the utility of this strategy was illustrated by late-stage modifications and photophysical property studies. The regioselectivity of radical addition and cyclization processes was demonstrated using both experimental studies and DFT calculations.