A 1,2- prototropy route and an iminium ion route to vinyl azomethine ylides are described. In both cases the vinyl azomethine ylides undergo 1,5-electrocyclisation to dihydropyrroles. In the former case the 1,5-electrocyclisation is solvent sensitive and competes with a prototropic process giving the imine of an α, β-unsaturated α-amino ester. The mechanism and solvent sensitivity are discussed. In
描述了到
乙烯基偶氮甲
亚胺基的1,2-原生质途径和
亚胺离子途径。在两种情况下,
乙烯基偶氮甲
亚胺基化物都经过1,5-电环化成二氢
吡咯。在前一种情况下,1,5-电环化是溶剂敏感的,并且与质子化过程竞争,从而产生亚
胺类的α,β-不饱和α-
氨基酯。讨论了机理和溶剂敏感性。在后一种情况下,二氢
吡咯经醛醇缩合进一步与醛反应。