Visible-Light-Induced Regioselective C(sp³)-H Acyloxylation of Aryl-2H-azirines with (Diacetoxy)iodobenzene

Abstract

A visible-light-promoted regioselective coupling of C(sp 3 )-H of aryl-2H-azirine and (diacetoxy)iodobenzene has been reported. Rose Bengal as an organophotoredox catalyst has been used in this reaction. The reaction proceeds under aerobic condition at room temperature. A variety of aryl-2H-azirines gives the corresponding acyloxylated azirines under this reaction conditions. The reaction goes through a radical pathway. The protocol is also applicable on gram-scale synthesis.

Recent Synthetic Applications of the Hypervalent Iodine(III) Reagents in Visible-Light-Induced Photoredox Catalysis

“…In 2019, Santra, Hajra, Majee and coworkers developed a method for regioselective coupling of C(sp 3 )-H of aryl-2 H -azirine and (diacetoxy)-iodobenzene (PIDA) using visible light irradiation (De et al, 2019 ) ( Figure 8 ). Aryl-2 H -azirines with different functional groups were converted into the corresponding acetoxylated azirines under aerobic condition.…”

Iodine-based reagents in photoredox-organocatalysis

“…72 Majee and coworkers developed a method for acyloxylation of 2H-azirine molecules using PhI(OAc)2 or PIDA as acyl source under visible light irradiation using organo-photocatalyst (Figure 10). 73 In this study, they concluded that 2 mol % of Rose Bengal (RB) as photocatalyst was good enough for the C(sp 3 )-H acyloxylation of 3-aryl-2H-azirines 26 using 2 equiv of PIDA under blue LED irradiation. Aryl rings containing electron-donating groups at -ortho, -meta, or -para positions provided a good yield of the…”

Advances in Oxosulfonylation Reaction

“…Recently, functionalizations using environment‐friendly catalysts such as organophotocatalysts are the most demanding among synthetic organic chemists as these methods can reduce the requirement of high temperature and toxicity [74–79] . In 2014, Yadav et al [56] .…”

“…Recently, functionalizations using environmentfriendly catalysts such as organophotocatalysts are the most demanding among synthetic organic chemists as these methods can reduce the requirement of high temperature and toxicity. [74][75][76][77][78][79] In 2014, Yadav et al [56] revealed a metal-free method for one-pot synthesis of a series of β-keto sulfoxides. Alkenes 14a reacted with aryl thiophenols 14b in presence of eosin Y as photocatalyst in acetonitrile solvent under irradiation of green light to afford β-keto sulfoxides 14c in 65-90% yields.…”