Boric acid as an efficient and green catalyst for the synthesis of 2-amino-4,6-diarylnicotinonitrile under microwave irradiation in solvent-free conditions

Abstract

Microwave irradiation has been used to improve the one-pot synthesis of substituted 2-amino-4,6-diarylnicoti-nonitrile in the presence of boric acid as an efficient and green catalyst under solvent-free conditions within 48-60 s. All the analogs that have not been reported previously were characterized by their melting points, IR, 1 H NMR, and 13 C NMR spectra. One of the structures was verified by the analysis of a single crystal. The reported synthetic procedure provided remarkable advantages such as short reaction times, excellent yield, facile workup, and the use of a green catalyst.