Photoredox Catalytic Phosphite-Mediated Deoxygenation of α-Diketones Enables Wolff Rearrangement and Staudinger Synthesis of β-Lactams
A novel visible-light-driven catalytic activation of C=O bonds by exploiting the photoredox chemistry of 1,3,2-dioxaphospholes, readily accessible from α-diketones and trialkyl phosphites, is reported. This mild and environmentally friendly strategy provides an unprecedented and efficient access to the Wolff rearrangement reaction which traditionally entails α-diazoketones as precursors. The resulting ketenes could be precisely trapped by alcohols/thiols to give α-aryl (thio)acetates and by imines to afford the valuable β-lactams in up to 99 % yields.
Jiang, Zhiyong,Li, Haijun,Wei, Guo,Yang, Hui
supporting information
p. 19696 - 19700
(2021/08/03)
Synthesis of chiral α-diarylacetic esters by stereospecific 1,2-aryl migration promoted by in situ generated acetals from benzoins
A simple protocol for the synthesis of α-diarylacetic esters from benzoins is described. In situ generated acetal assists rapid 1,2-aryl migration in a stereospecific manner, paving the way to make enantioenriched α-diarylacetic esters from easily accessi