Unified Metal-Free Regioselective Heck-Type Sulfonylation, Cyanation, Amination, Amidation of Alkenes by Thianthrenation

Abstract

Direct and site-selective C-H functionalization of alkenes under environmentally benign conditions represents a useful and attractive yet challenging transformation to access value-added molecules. Herein, a unified protocol for a variety of intermolecular Heck-type functionalizations of Csp2-H bond of alkenes has been developed by thianthrenation for the first time. The reaction features metal-free and operationally simple conditions for exclusive cine-selective C-H functionalization of aliphatic and aryl alkenes to forge C-C, C-N, and C-S bonds at room temperature, providing a general protocol for intermolecular Heck-type reaction of alkenes with nucleophiles (Nu = sulfinates, cyanides, amines, amides). Alkenes undergo cine-sulfonylation, cyanation, amination to afford alkenyl sulfones, alkenyl nitriles and enamines.

C(sp3)–H sulfinylation of light hydrocarbons with sulfur dioxide via hydrogen atom transfer photocatalysis in flow

“…The Michael addition reaction of ethane sulfinate intermediate with Nphenyl succinimide resulted in the formation of imide 30 in 56% yield. A cine-sulfonylation reaction was applied for the synthesis of highly electrophilic alkenyl sulfone 31 with a yield of 70% 36 . A two-step procedure was utilized for the synthesis of sulfonamides and sulfonate esters, involving a sulfonyl halide intermediate, leading to medicinally relevant compounds 32-36, including derivatizations of Amoxapine and (+)-Leelamine.…”