A simple and environmentally benign synthesis of novel spiro[indoline-3,5′-pyrano[2,3-d]pyrimidine] derivatives in water

Abstract

A green, convenient, and efficient one-pot synthesis of a new class of spiro[indolinepyranopyrimidine] derivatives was achieved in good yields by the multi-component reaction of N-alkyl-1-(methylthio)-2-nitroethenamine derived from the addition of various amines to nitroketene dithioacetal with isatin and barbituric acid derivatives in water at reflux conditions. Notably, the present method offers desirable advantages including good yields, use of water as green solvent, absence of catalyst, simple workup procedure, and easy purification process with no chromatographic technique.