Photomediated One-Pot Three-Component Approach Enables the Formal Direct N-Acylation/Sulfonylation and α-C-H Functionalization of 1,2,3,4-Tetrahydroisoquinoline.

ABSTRACT

N-Acyl/sulfonyl-α-functionalized 1,2,3,4-tetrahydroisoquinolines (THIQs) are significant structural motifs in organic synthesis and drug discovery. However, the one-pot approach enabling direct difunctionalization of THIQs remains challenging. Herein we report a photomediated one-pot three-component strategy to access N-acyl/sulfonyl-α-functionalized THIQs. This method features the use of oxygen (from air) as the green oxidant, high atom and step economy, and decent structural diversity. The synthetic applicability of the method was further demonstrated via the facile construction of valuable bioactive molecules. Mechanistic studies indicated that oxidation with singlet oxygen and the acceptor-less dehydrogenation were involved in the photoredox process.