Hydrosulfonylation of Alkenes with Sulfonyl Imines via Ir/Cu Dual Photoredox Catalysis.

Sulfonamides exhibit the advantages of wide prevalence, excellent prefunctionalization capability, and broad functional group compatibility. We report here utilizing sulfonyl imines as sulfonyl radical precursors for hydrosulfonylation of activated alkenes via visible-light irradiation. By preinstallation of functional groups into the sulfonamides and subsequent hydrosulfonylation, a variety of complex sulfones were synthesized with good efficiency under Ir/Cu dual photoredox catalysis. Additionally, this protocol expands the research in late-stage N-S bond modification in sulfonamides.

Visible-Light-Mediated Late-Stage Sulfonylation of Anilines with Sulfonamides.

A visible-light-mediated late-stage sulfonylation of anilines with sulfonamides under simple reaction conditions is presented. Various primary or secondary sulfonamides including several pharmaceuticals were incorporated successfully via N-S bond activation and C-H bond sulfonylation. The synthetic utility of this strategy is highlighted by the construction of complex anilines bearing diverse bioactive groups.

Catalyst-free arylation of sulfonamides via visible light-mediated deamination.

A novel arylation of sulfonamides with boronic acids to afford numerous diaryl sulfones via a visible light-mediated N-S bond cleavage other than the typical transition-metal-catalyzed C(O)-N bond activation is described. This methodology, which represents the first catalyst-free protocol for the sulfonylation of boronic acids, is characterized by its simple reaction conditions, good functional group tolerance and high efficiency. Several successful examples for the late-stage functionalization of diverse sulfonamides indicate the high potential utility of this method in pharmaceutical science and organic synthesis.

Base-Mediated Borylsilylation/Silylation of Ammonium Salts with Silylborane.

This work describes a base-mediated borylsilylation of benzylic ammonium salts to synthesize geminal silylboronates bearing benzylic proton under mild reaction conditions. Deaminative silylation of aryl ammonium salts was also achieved in the presence of LiOtBu. This strategy which is featured with high efficiency, mild reaction conditions, and good functional group tolerance provides efficient routes for late-stage functionalization of amines.