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An efficient, one-pot approach has been established for synthesizing a wide range of 3-amino-[1,2,4]-triazolo pyridines and related heterocycles from the electrochemically induced desulfurative cyclization of 2-hydrazinopyridines with isothiocyanates. The protocol allows for the formation of C-N bonds under simple conditions without transition metals or external oxidants. The practicability of this strategy is demonstrated by its broad substrate scope, good functional group compatibility, and gram-scale synthesis. The late-stage modification of 3-amino-[1,2,4]-triazolo pyridines enables us to obtain several molecules with potent anticancer activity.

Borylated aza-arenes are of great importance in the area of organic synthesis. A radical borylative cyclization of isocyanoarenes with N-heterocyclic carbene borane (NHC-BH3) under metal-free conditions was developed. The reaction allows the efficient assembly of several types of borylated aza-arenes (phenanthridines, benzothiazoles, etc.), which are difficult to access using alternative methods. Mild reaction conditions, a good functional-group tolerance, and generally good efficiencies were observed. The utility of these products is demonstrated, and the mechanism is discussed.

A novel cascade Cp*Rh(III)-catalyzed C–H alkylation/Cu(II)-promoted α-oxygenation which enabled a three-component carboxygenation of activated alkene is reported. Mild reaction conditions, broad substrate scope, and good functional group tolerance were observed. The synthetic utility of the protocol was showcased by the facile transformations of the product to a variety of structurally diverse molecules. Preliminary mechanistic studies were conducted.

Cp*Co(III)-catalyzed annulations of 2-alkenylphenols with CO for the synthesis of coumarin derivatives have been developed. The reaction features mild reaction conditions, broad substrate scope, and good functional group tolerance. Preliminary mechanistic studies were conducted, suggesting that C–H activation is the turnover limiting step. Furthermore, the efficiency of this reaction was demonstrated by the rapid total synthesis of three natural products herniarin, xanthyletin, and seselin.

3-Pinanamine is a prevalent motif in medicinal chemistry and asymmetric synthesis. In line with the pursuit of novel 3-pinanamine based anti-influenza virus A agent, the direct functionalization of 3-pinanamine was achieved by using Pd-catalyzed C(sp(3))-H activation logic. Good substrate scope and functional group tolerance were observed. The reaction represents a rare example of a direct functionalization of an aliphatic amine at the remote δ position.