Photocatalyst-free visible light driven synthesis of (E)-vinyl sulfones from cinnamic acids and arylazo sulfones

Visible Light-Driven, Gold(I)-Catalyzed Preparation of Symmetrical (Hetero)biaryls by Homocoupling of Arylazo Sulfones

“…In most cases, a 15 mol % amount of (PPh 3 )AuCl to achieve satisfactory results (see dihaloderivatives 24 – 26 and 2,2′-diphenoxybiphenyl 29 ). As observed in previous works, 30 the presence of a nitro group in the ortho -position in arylazo sulfones prevented the arylation as confirmed here, leading to the exclusive formation of nitrobenzene instead of the desired compound 28 .…”

“…We recently focused on arylazo sulfones that incorporate a dyedauxiliary group (−N 2 SO 2 CH 3 ) responsible for their color and their photoreactivity, useful precursors of reactive intermediates such as aryl, alkyl(aryl)sulfonyl, and aryldiazenyl radicals. 28 These intermediates have been exploited in different synthetic protocols under photocatalyst-free conditions for the visible light-driven forging of C–C 29 as well as C-heteroatom 30 bonds.…”

Visible Light as the Key for the Formation of Carbon–Sulfur Bonds in Sulfones, Thioethers, and Sulfonamides: An Update

“…Firstly, Ar 2 S • a radicals are generated via a SET process combined with an energy transfer from ground state 3 (E)-Vinyl sulfones 132 were obtained from cinnamic acids 34 and bench-stable arylazo sulfones 129, as sulfonyl radical precursors, in a photocatalyst-free visible-lightmediated decarboxylative sulfono-functionalization (Scheme 46). 69 Both vinyl aryl sulfones as well as vinyl alkyl sulfones were obtained. A radical pathway mediated by visible light without any photocatalyst or external oxidant was suggested.…”

Dyedauxiliary Group Strategy for the α-Functionalization of Ketones and Esters

“…Thus, different intermediates (aryl diazenyl, aryl radicals, sulfonyl radicals, and aryl cations) can be generated selectively, by tuning the reaction conditions (light sources, reaction media, coupling partner). Such behavior was exploited in the optimization of synthetic protocols for aryl-carbon − and aryl-heteroatom bond formation − as well as aryldiazenylation and sulfonylation of alkenes. , …”