Evidence for a Non-Concerted, Dissoziative Mechanism of the Palladium-Catalyzed “Enolate Claisen Rearrangement” of Allylic Esters
作者:Manfred Braun、Panos Meletis、Wolfgang Schrader
DOI:10.1002/ejoc.201000874
日期:——
In an enolate Claisen rearrangement, deprotonated allyl phenylacetate undergoes a smooth conversion at –78 °C to 2-phenyl-4-pentenoic acid under palladium(0) catalysis. By using labelled starting materials in crossover experiments, the reaction is shown to follow a dissoziative, non-concerted, non-[3,3]-sigmatropic mechanism that involves palladium complexes and carboxylic-acid dianions as intermediates
在烯醇克莱森重排中,去质子化的苯乙酸烯丙酯在 –78 °C 下在钯 (0) 催化下顺利转化为 2-苯基-4-戊烯酸。通过在交叉实验中使用标记的起始材料,显示反应遵循解离、非协调、非 [3,3]-σ 机制,涉及钯配合物和羧酸二价阴离子作为中间体。