A palladium-catalyzed spirocyclization reaction is reported, which is proposed to arise via insertion of an oxabicycle into a palladacycle, formed from carbocyclization and a C–H functionalization sequence. Mechanistic studies suggest the insertion is diastereoselective and a post-catalytic retro-Diels–Alder step furnishes an alkene, wherein the oxibicycle has served as an acetylene surrogate. Aryl
据报道,
钯催化的螺环化反应是通过将氧杂环插入由碳环化和 C-H 官能化序列形成的
钯环中而产生的。机理研究表明插入是非对映选择性的,并且后催化逆狄尔斯-阿尔德步骤提供了烯烃,其中氧双环充当了
乙炔替代物。在相同的反应条件下,芳基
碘化物和
氨基
甲酰氯作为起始原料是相容的,从而能够聚合和互补合成螺
吲哚以及其他氮
杂环化合物。这些螺
吲哚可以实现以前无法实现的进一步转化。