N-Substituted enaminones from 3-aminobutenoic acids and 1,4-naphthoquinones

Abstract

N-Substituted 3-aminobut-2-enoic acid esters (enaminones) were prepared by condensing methyl (or ethyl) acetoacetate with (2,2-dimethoxyethyl)amine, (4,4-dimethoxybutyl)amine, N-(2'-aminoethyl)-pyrrolidine and N-(2'-aminoethyl)morpholine to produce enaminones (3)-(6) respectively. A cyclic enaminone (11) was prepared from dimethyl acetylenedicarboxylate. The N-substituted amino quinones (12)-(14) are also reported, together with their ¹³C n.m.r. data and assignments.