Visible-light-induced photoxidation-Povarov cascade reaction: synthesis of 2-arylquinoline through alcohol and N-benzylanilines under mild conditions via Ag/g-C3N4 nanometric semiconductor catalyst.

With a Ag/g-C3N4 nanometric semiconductor as the photocatalyst, 2-arylquinolines were synthesized through a photoxidation-Povarov cascade reaction of N-benzylanilines and alcohols under visible light irradiation. Under the blue light of a 3 W LED, good yields were achieved for various substrates in oxygen at room temperature. This methodology provides a green and mild alternative for the formation of 2-arylquinoline derivatives. Remarkably, the Ag/g-C3N4 nanocomposite can be conveniently recovered and reused several times with satisfying yields.

Recyclable Cu/C3N4 composite catalyzed AHA/A3 coupling reactions for the synthesis of propargylamines.

The heterogeneous Cu/C3N4 catalyst was found to be efficient for the synthesis of propargylamines using a three-component coupling reaction of alkynes, CH2Cl2 and amines (AHA) without additional base. Moreover, the catalyst also showed highly catalytic activity in the synthesis of C1-alkynylated tetrahydroisoquinolines (THIQs) via an A3 reaction of alkynes, aldehydes and THIQ. The Cu/C3N4-catalyzed multicomponent reactions exhibited good functional group tolerance in most examples. Furthermore, the easily prepared Cu/C3N4 catalyst could be recovered and reused conveniently over 5 times without losing catalytic activities.