Substrate-controlled reactions have been developed for the synthesis of spirocyclopropylpyrazolones and bicyclic 4,5-dihydropyrazoles from 1,2-diaza-1,3-dienes and sulfur ylides. These protocols were carried out under mild reaction conditions without any additives in generally moderate to good yields. Plausible mechanisms for the transformations were proposed.
Visible-Light-Driven Radical Multicomponent Reaction of 2-Vinylanilines, Sulfonyl Chlorides, and Sulfur Ylides for Synthesis of Indolines
作者:Mukund M. D. Pramanik、Fan Yuan、Dong-Mei Yan、Wen-Jing Xiao、Jia-Rong Chen
DOI:10.1021/acs.orglett.0c00602
日期:2020.4.3
A visible-light-driven photoredox-catalyzed multicomponent reaction of 2-vinylanilines, sulfonyl chlorides, and sulfur ylides is described. This protocol features redox-neutral mild conditions, a broad substrate scope, and good functional group tolerance, providing access to various sulfonated 2,3-disubstituted indolines. The product can be transformed to a diverse range of functionalized indoles by
A visible-light-driven and room temperature photo-Wolff-Kischner reaction of sulfur ylides and N-tosylhydrazones has been developed for the first time to provide modular access to alkene synthesis. The high functional group tolerance and broad substrate scope were demonstrated by more than 60 examples. Both E- and Z-olefinic stereochemistry in the products could be controlled with excellent stereoselectivity
Batting the ylides: A simple procedure carried out under mild conditions allows the direct and efficientsynthesis of structurally diverse indoles. This approach involves a cascadereaction of sulfurylides and N‐(ortho‐chloromethyl)arylamides (see scheme).
Under control: A formal [4+1]/[3+2] cycloaddition cascade of sulfurylides and alkene‐tethered nitroolefins has been developed, and provides an efficient synthesis of fused polycyclic heterocyclic compounds in good to excellent overall yields with excellent diastereocontrol (see scheme). A catalytic asymmetric variant of this reaction has also been disclosed.