Copper-catalyzed sp3-carbon radical/carbamoyl radical cross coupling: A direct strategy for carbamoylation of 1,3-dicarbonyl compounds

A novel copper-catalyzed sp 3 -carbon radical/carbamoyl radical cross-coupling protocol for the construction of C(sp 3 )-C(O) bond is described. This provides a straightforward method for synthesis of 2-carbamoyl-1,3-dicarbonyl compounds in good to excellent yields under mild conditions. Mechanistic studies confirms the generation of both carbamoyl and C(sp 3 )-centered radicals directly from oxidation of C(sp 3 )-H bond of formamides and 1,3-dicarbonyl compounds, respectively. • The reaction of 1,3-dicarbonyl compounds and formamides afforded the 2-carbamoyl-1,3-dicarbonyl compounds. • This protocol provided an efficient construction of C(sp 3 )−C(O) bond strategy. • Mechanistic studies confirm that the products were formed through radical-radical cross-coupling process.