Reactions of phosphines with acetylenes. Part XII. The mechanisms of 1,2-aryl migrations common to αβ-unsaturated phosphonium salts and “Wittig-type” phosphonium betaines
作者:Eileen M. Richards、John C. Tebby
DOI:10.1039/j39710001059
日期:——
The reactions of (a) methylenetriphenylphosphorane with benzaldehyde in alcohol, (b) triarylphosphines with styrene oxide in alcohol, and (c) triarylphosphines with electrophilic acetylenes and water, and (d) the alkaline hydrolysis of αβ-unsaturated phosphonium salts, all involve the formation of an equilibrium mixture of a betaine, a hydroxyethylphosphonium salt, an αβ-unsaturated phosphonium hydroxide
(a)亚甲基三苯基膦与酒精中的苯甲醛,(b)三芳基膦与苯乙烯中的氧化苯乙烯的反应,以及(c)三芳基膦与亲电乙炔和水的反应,以及(d)αβ-不饱和phospho盐的碱性水解,都涉及形成甜菜碱,羟乙基phosph盐,αβ-不饱和氢氧化hydroxide和相应的五共价氧磷烷的平衡混合物。在温和的碱性条件下,产物主要来自于乙烯基催化的膦氧烷的碱催化重排,但在更碱性的条件下,甜菜碱的分解占主导地位。