A microwave assisted tandem synthesis of quinazolinones using ionic liquid supported copper(II) catalyst with mechanistic insights.

Quinazolinone is a preferred structural motif with notable pharmacological activity that is present in a wide range of naturally occurring compounds. A microwave assisted tandem cyclooxidative method has been developed to afford quinazolinones via a recyclable ionic liquid supported copper catalyst. This sustainable method exhibits operational simplicity through a rapid, clean, and energy-efficient route and a variety of 2-substituted quinazolinones are obtained in excellent yields. In addition, this innovative approach enables us to develop a library of nitriles in an environment-friendly synthetic protocol. Moreover, the catalyst can be recycled and reused up to three consecutive cycles without any significant loss of catalytic activity. Further organic transformation of the synthesized quinazolinones was carried out to afford reported as well as novel bioactive heterocyclic compounds.