Substituent-controlled divergent cyclization reactions of benzo[c][1,2]dithiol-3-ones and hexahydro-1,3,5-triazines

Abstract

The first divergent cyclization reaction of benzo[c][1,2]dithiol-3-ones to assemble six- and eight-membered N-containing heterocycles is displayed herein. This unprecedented formal [4 + 4]/[4 + 2] cycloaddition of 3H-benzo[c][1,2]dithiol-3-ones and hexahydro-1,3,5-triazines is controlled by the N-substituent group of hexahydro-1,3,5-triazines. This newly discovered tactic features transition-metal-free, no inert gas protection, easy operation, mild conditions, decent yields, broad substrate scope and accessible scalability.