Photosensitized Vicinal Sulfonylamination of Alkenes with Oxime Ester and DABCO·(SO₂)₂

Abstract

A metal-free photosensitized three-component reaction of oxime esters, alkenes, and DABCO•(SO 2 ) 2 was developed. This protocol could accommodate a wide substrate scope, including activated and unactivated alkenes and aryl and aliphatic carboxylic acid oxime esters, delivering a broad range of βamino sulfones in moderate to high yields. The insertion of SO 2 as a linker moiety allows the manipulation of the functionality in the reaction process, expanding the utility of oxime esters as bifunctional reagents.

Functionalization of Cubane Formation of C−C and C−Heteroatom Bonds

“…Other photochemical conditions have been developed to create a C−S bond on a cubane from a cubyl oxime ester in the presence of DABCO•(SO 2 ) 2 , an SO 2 surrogate [85–89] . When alkyl oxime ester 40 was irradiated at 390 nm in the presence of the commercially available PhotoSensitizer ( PS ) 2,4‐diethyl‐thioxanthone, in the presence of DABCO•(SO 2 ) 2 in ethylacetate, the cubyl β‐aminosulfone 85 was isolated in 40 % yield.…”

Access to chiral β-amino sulfones from acrylamides and sulfur dioxide by iron catalysis

“…Li reported a novel electrochemical intermolecular 1,2-aminosulfonylation of alkenes for producing β-amino sulfones 7 (Scheme 1b, top). Wu, 8 Xu 9 and Yang 10 respectively achieved amino-sulfonylation of alkenes using nitrile compounds (Scheme 1b, left) or imine compounds (Scheme 1b, bottom) through photocatalysis. Due to the fact that azide group could be easily reduced to amine group, 11 sulfonyl-azidation of alkenes is an alternative pathway to access β-amino sulfones.…”

Photoredox‐Catalyzed Preparation of Sulfones Using Bis‐Piperidine Sulfur Dioxide – An Underutilized Reagent for SO2 Transfer

“…[14,15] Although several photochemical strategies to incorporate aryl (and other sp 2 ) radicals into SO 2 sources have been developed, [16][17][18][19][20][21][22][23][24][25]26,27] there are somewhat fewer examples of alkyl radicals being trapped by SO 2 , [28][29][30][31][32][33][34][35][36] and fewer still, established general methods that allows the incorporation of both substituents. [37][38][39][40] Those that do have limited scope due to the required use of UV light irradiation in their preparation. The exception to this is the recent use of photocatalytic strategies with thianthrenium salts, [41] which has made the preparation of sulfones from aryl and alkyl radicals possible and has the advantage of tolerating a wider range of functional groups than previous UV light procedures.…”