Sequential nature of the thermal reaction of stearic acid with some 1,2-diamines

Abstract

The thermal reactions of stearic acid with ethane-1,2-diamine, bis-(2-aminoethyl)amine, and 2-(2-aminoethylamino)ethanol with a heavy hydrocarbon oil as solvent were investigated. The reactions proved general and followed a sequential pattern of (i) salt formation, (ii) acylation of the amine, and (iii) cyclisation of the amide, each successive step taking place at a higher temperature. The amounts of water formed during the reaction were consistent with the foregoing scheme. The structures of the products were determined from i.r. and ¹H and ¹³C n.m.r. data