Brønsted Acid-Catalyzed Regioselective Coupling between Azoles and Arylcyclobutenes.

Herein, we describe a protocol for Brønsted acid-catalyzed regioselective coupling of azoles such as pyrazoles, 1,2,3-triazole, 1,3,4-triazole, benzotriazole, indazole and tetrazole, to cyclobutenes. These azoles could be directly coupled with various arylcyclobutenes with high site-selectivity, offering a distinct entry to more functionalized cyclobutanes. The usage of inexpensive TsOH•H2O catalyst, broad substrate scope, and open-air conditions make this protocol practically viable.

Cobalt-Catalyzed Nitrogen Atom Insertion in Arylcycloalkenes.

Developing strategies enabling the modification of underlying molecular frameworks facilitates access to underexplored chemical spaces. Skeletal editing is an emerging technology for late-stage diversification of bioactive molecules. However, the current state of this knowledge remains undeveloped.