multi-step route starting with 1,1,5,5-tetrachloro-penta-1,4-dien-3-one (). The tris(dialkylamino)-substituted , undergo electrophilic substitution. They are better represented as polymethine-like systems. The 2,6-bis(dialkylamino)-substituted , display a significantly increased donor-reactivity at the carbonyl-oxygen.
2,4,6-三(二烷基
氨基)
吡喃鎓盐和2,6-二(二烷基
氨基)-2H-
吡喃-4-酮以及它们的
硫代类似物,已制备了通过启动1,1,5-多步途径,5-四
氯戊-1,4-二烯-3-酮()。(二烷基
氨基) -取代的三,经历亲电取代。它们可以更好地表示为类似聚次甲基的系统。2,6-双(二烷基
氨基)-取代的,在羰基氧上显示出显着增加的供体反应性。