Access to N-Heterocyclic Molecules via Ru(II)-Catalyzed Oxidative Alkyne Annulation Reactions

Abstract

In last few decades, the transition metal-catalyzed C-H bond activation and alkyne annulation reactions have turned out to be effective methods for the construction of highly important heterocycles. In particular, the Ru(II) catalysts have been used for the oxidative coupling between an internal alkynes and readily available nitrogen directed compounds in a rapid and sustainable manner. The Ru(II) catalysts are very much beneficial due to their stability in both air and water, ease of preparation, inexpensive than those of Rh(III) and designer Co(III) catalysts usually used for alkyne annulation reactions, requirement of mild reaction conditions, and compatible with various oxidants. Owing to these advantages of Ru(II) catalysts herein, we attempt to highlight the recent development in C-H activation and annulation reactions, which lead to the formation of several important N-heterocycles.

Metal-catalyzed reactions of organic nitriles and boronic acids to access diverse functionality

“…45 Therefore, the transition metal-catalyzed synthesis of N,O-heterocycles is being developed through various reaction strategies. 46 Nitrogen heterocycles such as pyrroles, 47 a pyridines/pyridinos, 47 b , c indoles, 47 d isoquinolines, 47 e and quinozalines/quinolizines 47 f , g have extensively been used as the building blocks of many biologically as well as pharmaceutically active compounds. They also constitute the core motifs of many natural products and have found wide application in the field of materials sciences.…”