Spirobisheterocyclization of 5-(Methoxycarbonyl)-1H-pyrrol-2,3-diones by the action of enaminoesters. Crystal and molecular structure of 1,7-diazaspiro[4.4]nonane

Abstract

1-Aryl-4-aroyl-5-(methoxycarbonyl)-1Н-pyrrole-2,3-diones react with methyl 4-aryl-2-(arylamino)-4-oxobut-2-enoates with the formation of methyl 1,7-diaryl-4,9-diaroyl-3-hydroxy-2,6-dioxo-1,7-diazaspiro[4.4]nona-3,8-diene-8-carboxylates.