posted on 2024-02-08, 13:08authored bySrashti Bhardwaj, Dinesh Kumar Gopalakrishnan, Shalu Deshwal, Raju Sen, Vikas Tiwari, Tarak Karmakar, Janakiram Vaitla
Multicomponent
reactions that involve carbenes with nucleophiles
and electrophiles have demonstrated broad applications in synthetic
chemistry. However, because of the high reactivity of transient carbenes,
reactions involving two carbene precursors with the nucleophile in
the presence of a metal catalyst remain unexplored. Herein, a three-component
stereoselective gem-difunctionalization of diazo
compounds with thiols and vinyl sulfoxonium ylide is disclosed via
Co(II)-based metalloradical catalysis. The key aspect of the present
strategy is to exploit the intrinsic difference in the reactivity
of vinyl sulfoxonium ylides and diazo compounds with thiol and metal
catalysts. The present Doyle–Kirmse rearrangement of a sulfonium
ylide involves a convergent assembly of two in situ-generated intermediates, such as allyl sulfide and α- metalloalkyl
radical complex, to provide expeditious access to tertiary sulfide
scaffolds. Combined experimental and quantum chemical calculations
unveil the intricate mechanism of this three-component reaction. Furthermore,
theoretical studies on noncovalent interactions of selectivity-determining
transition states explain the origin of the experimentally obtained
diastereoselectivity.