A modular photoredox route towards sulfoximines

Abstract

We report a modular photoredox strategy for the synthesis of aryl vinyl sulfoximines from sulfinamide and vinyl halide starting materials. This strategy demonstrates a difunctionalization of sulfinamides to sulfoximine products with excellent configurational retention and stereoselective trans alkenes. Under mild redox conditions, we propose the generation of a nitrogen centered radical that is resonance stabilized by a sulfur radical partner, increasing overall radical lifetime. This strategy we disclose is thus well suited for vinyl halide radical capture, leading to sulfoximine products. This process also entails broad modularity about the alkene, arene, and acyl protecting group, providing synthetic chemists multiple functional handles allowing for further exploration into the physicochemical properties that have shown promise in recent studies.

Synthesis of Pyrazolesulfoximines Using α-Diazosulfoximines with Alkynes

“…With the emergence of sulfoximines in drug discovery, their synthesis has seen notable advances . Developed strategies include N-transfer to sulfoxides, N,O transfer to sulfides, and several approaches to C–S bond formation, involving nucleophilic and electrophilic sulfur reagents . Despite this, there remain relatively few sulfoximine containing reagents whereby a preformed sulfoximine motif can be installed in a strategic step.…”

“… 3 Developed strategies include N-transfer to sulfoxides, 10 N,O transfer to sulfides, 11 and several approaches to C–S bond formation, involving nucleophilic 12 and electrophilic sulfur reagents. 13 Despite this, there remain relatively few sulfoximine containing reagents whereby a preformed sulfoximine motif can be installed in a strategic step. In 2005, Bolm demonstrated the cross-coupling of bromophenyl sulfoximine in Suzuki and Stille cross-coupling and Buchwald–Hartwig amination reactions.…”