The zwitterionic intermediates (2a) in the oxidation of ortho-alkylphenols (1) and bis(sulfonium ylide) 3 form reasonably stable 2:1-complexes (4), in which the ortho-quinone methide (oQM) moieties are not present in quinoid form with the exocyclic in-plane methylene group, but as zwitterionic, aromatic conformer having an out-of-plane exocyclic methylene group. The complex 7 derived from the α-tocopherol
邻烷基
苯酚(1)和双(鎓内鎓盐)3氧化中的两性离子中间体(2a)形成相当稳定的2:1配合物(4),其中不存在邻
甲基苯醌(o QM)部分以醌型形式具有环外平面内亚甲基,但作为两性离子芳族构象异构体,具有平面外环外亚甲基。全面表征了α-
生育酚模型化合物PMC(5)衍生的配合物7。如示例性证明的,该加合物可以有利地在有机合成中用作“稳定ö QMS”。