Metal-Free Visible-Light Induced Cross-Dehydrogenative Coupling of Tertiary Amines with Diazo Compounds

The first visible-light induced cross-dehydrogenative coupling between tertiary amines and diazo compounds is described. The reaction proceeds smoothly under mild and metal-free conditions by using air or O2 as the oxidant, affording various β-amino-α-diazo adducts in moderate to good yields with broad substrate scopes. The resulting products were successfully employed for the synthesis of 4- or 5-ester N-aryl-2,3-dihydro­benzo­[d]­azepines with high regioselectivity simply switched by the selection of the transition metal catalysts.