Cs2CO3 as a source of carbonyl and ethereal oxygen in a Cu-catalysed cascade synthesis of benzofuran [3,2-c] quinolin-6[5-H]ones.

The simultaneous construction of C-C, C-O, and C-N bonds utilizing Cs2CO3 as a source of both carbonyl (CO) and ethereal oxygen and a cascade synthesis of benzofuro[3,2-c]quinolin-6(5H)-one have been achieved using a combination of Cu(OAc)2 and Ag2CO3. A plausible mechanism has been proposed for this unprecedented transformation.