Photoredox Catalytic Phosphine-Mediated Deoxygenative Hydroacylation of Azobenzenes with Carboxylic Acids
Jingya Yang, Cunhui Wang, Bao Huang, Hongyan Zhou, Jiangjiang Li, Xiaojun Liu
Abstract
The convenient and precise preparation of N, N ′-diarylhydrazides, especially from readily available raw materials, remains highly challenging. Here, a photoredox catalytic phosphine-mediated deoxygenative hydroacylation of azobenzenes with abundant and readily available carboxylic acids has been developed. With Ir[dF(CF 3 )ppy] 2 (dtbbpy)PF 6 as the photocatalyst, the reactions proceeded smoothly in the presence of PPh 3 under visible light irradiation, delivering various N, N ′-diarylhydrazides in up to 92% yields. Mechanistic studies revealed that the reaction proceeds via photoredox catalysis and phosphoranyl-radical-mediated C–O bond cleavage of carboxylic acids.