Tetraalkyl cyclobutene-1,2,3,4-tetracarboxylates, prepared by intramolecular Wittig reaction between a vinylphosphonium salt and diethyl 2-oxobutanedioate, undergo electrocyclic ring-opening reactions, in boiling toluene, to produce highly electron-deficient 1,3-dienes.
乙烯基鏻盐和 2-oxobutanedioate 二
乙酯通过分子内 Wittig 反应制备的
环丁烯-1,2,3,4-四
羧酸四烷基酯在沸腾的
甲苯中发生电环开环反应,生成高度缺电子的 1,3 二烯。