Microwave-assisted efficient synthesis of spiro-fused heterocycles under solvent-free conditions
作者:Ahmad Shaabani、Ayoob Bazgir
DOI:10.1016/j.tetlet.2004.01.154
日期:2004.3
Spiro-fused heterocycles were synthesized in good to high yields by a pseudo four-component reaction of an aldehyde, urea and a cyclic beta-diester or a beta-diamide such as Meldrum's acid or barbituric acid derivatives using microwave irradiation under solvent-free conditions. (C) 2004 Elsevier Ltd. All rights reserved.
Synthesis of spiro-fused heterocycles under aerobic conditions by using polymer gel-entrapped catalyst
Abstract An expedient synthesis of spiro-fused heterocycles from multi-component reaction of urea, aryl aldehydes and Meldrum’s or barbituric acid by using polymer gel-entrapped catalyst under aerobic conditions at ambienttemperature is reported. The developed protocol is simple, green, atom-economical and includes mild reaction conditions, does not involve tedious workup or purification procedure