Aerobic Oxidative Synthesis of Formamides from Amines and Bioderived Formyl Surrogates.

Herein 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 (O) as oxidant on g-CN supported Cu catalysts. Combined characterization data from EPR, XAFS, XRD and XPS revealed the formation of single CuN sites on supported Cu/CN catalysts. EPR spin trapping experiments disclosed ⋅OOH radicals as reactive oxygen species and ⋅NRR 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 ⋅NRR and ⋅OOH radicals based on the well-equilibrated Cu and Cu cycle. Our catalyst has much higher activity (TOF) than those based on noble metals.