Cu-Catalyzed Cross-Dehydrogenative Coupling of Heteroaryl C(sp2)-H and Tertiary C(sp3)-H Bonds for the Construction of All-Carbon Triaryl Quaternary Centers.

A Cu-catalyzed protocol for cross-dehydrogenative coupling of benzofuranones with quinolines, indoles, carbazoles, and thiophene, which furnishes highly functionalized 3,3-diaryl benzofuranones bearing a three aryl quaternary carbon center at the C3 position in good yields, has been developed. A radical mechanism is proposed.