Cooperative iridium complex-catalyzed synthesis of quinoxalines, benzimidazoles and quinazolines in water. Issue 8 (19th March 2019) - Chakrabarti, Kaushik
Abstract : A sustainable protocol for the synthesis of various pharmaceutically relevant N-heterocyclic moieties was developed in water. A metal–ligand cooperative mechanism was proposed for this system based on kinetic and DFT studies. Abstract : Herein, an efficient methodology for the synthesis of a diverse class of N-heterocyclic moieties, such as quinoxalines, benzimidazoles and quinazolines, was developed in water using bio-renewable alcohols. The quinoxalines were successfully synthesized from a wide range of diamines and nitroamines with diols in air. Interestingly, benzimidazoles and quinazolines were synthesized with excellent isolated yields without using any external base. Finally, the preparative scale synthesis of various N-heterocycles and pharmaceutically active quinoxalines established the practicability of this protocol. For this iridium system, a metal–ligand cooperative mechanism was proposed based on kinetic and DFT studies.