The Formation of Intermediate Lactones During Aminolysis of Diethyl Xylarate

Abstract

The aminolysis of diethyl xylarate was found to proceed through intermediate lactones. In dimethyl sulfoxide at 30°C in the presence of etha-nolamine/ the 1,5-diester is rapidly converted into ethyl d, l-xylaro-1,4-lactone, which reacts with the primary amine to give ethyr N-(2-hydroxyech-yl)-d, l-xylaramide. This compound then forms N-(2-hydroxyethyl)-d, l-xylara-mide-2T5-lactone, which in turn reacts with ethanolamine to produce the final product, N,N'-bis-(2-hydroxyethyl)-d-l-xylaramide. This sequence of reactions was established by ¹³C NMR spectroscbpy.