Ester exchange in ethyl N-substituted-4-hydroxy-5-oxo-3-pyrroline-3-carboxylates
Abstract
Alkyl N-substituted-4-hydroxy-5-oxo-3-pyrroline-4-carboxylates are prepared by condensation of diethyl oxalate with alkyl N-substituted 3-aminopropionates. These amino-esters are formed by ester exchange between the ethyl amino-esters and sodium alkoxides. Thermal disproportionation of ethyl N-benzyl-3-aminopropionate followed by condensation with diethyl oxalate gave NN′-dibenzyl oxamide.