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 alpha-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 alpha-diazoketones as precursors. The resulting ketenes could be precisely trapped by alcohols/thiols to give alpha-aryl (thio)acetates and by imines to afford the valuable beta-lactams in up to 99% yields.

Automated summary

A novel visible-light-driven catalytic activation of C=O bonds is achieved by exploiting the photoredox chemistry of 1,3,2-dioxaphospholes, providing an efficient pathway for the synthesis of α-aryl (thio)acetates and β-lactams with yields up to 99%.