Aerobic Oxidative Synthesis of Formamides from Amines and Bioderived Formyl Surrogates

Abstract

AbstractHerein we present a new strategy for the oxidative synthesis of formamides from various types of amines and bioderived formyl sources (DHA, GLA and GLCA) and molecular oxygen (O2) as oxidant on g‐C3N4 supported Cu catalysts. Combined characterization data from EPR, XAFS, XRD and XPS revealed the formation of single CuN4 sites on supported Cuphen/C3N4 catalysts. EPR spin trapping experiments disclosed ⋅OOH radicals as reactive oxygen species and ⋅NR1R2 radicals being responsible for the initial C−C bond cleavage. Control experiments and DFT calculations showed that the successive C−C bond cleavage in DHA proceeds via a reaction mechanism co‐mediated by ⋅NR1R2 and ⋅OOH radicals based on the well‐equilibrated CuII and CuI cycle. Our catalyst has much higher activity (TOF) than those based on noble metals.