Synthesis of quinazoline derivatives by using biginelli type reaction under microwave irradiation

Abstract

Microwave irradiation has become a very convenient tool in organic synthesis. Microwave technology in organic chemistry has been explored extensively within the last decade. A Biginelli one-pot three-component reaction involving cyclohexanone, aromatic/or heterocyclic aldehyde, and urea or thiourea was applied in this work to prepare quinazoline-2(1H) one derivatives under solvent free and microwave irradiation assistance method.

Scheme 1

It significantly shortens the reaction time and is best suited for the chemical reactions carried out on solid supports as well. Microwave-assisted reactions are attractive in offering reduced pollution and offer low cost together with simplicity in processing and handling. Thereby this method plays an important role in the development of Green Chemistry. All the synthesized compounds was subjected to both physical and chemical methods of analysis, especially spectroscopic method (UV, IR, 1H NMR, 13C NMR and Mass spectra) for assuring the molecular structure of the synthesized compounds. In conclusion, we have evolved a much improved modification of Biginelli reaction exploiting FeCl3 as a catalyst without using any organic solvent with increased yield, while the reaction time shortened from 4-5 h to a few minutes under microwave irradiation.