Redox and Lewis Acid Relay Catalysis: A Titanocene/Zinc Catalytic Platform in the Development of Multicomponent Coupling Reactions
作者:Joseph B. Gianino、Catherine A. Campos、Antonio J. Lepore、David M. Pinkerton、Brandon L. Ashfeld
DOI:10.1021/jo501890z
日期:2014.12.19
A titanocene-catalyzed multicomponent coupling is described herein. Using catalytic titanocene, phosphine, and zinc dust, zinc acetylides can be generated from the corresponding iodoalkynes to affect sequential nucleophilic additions to aromatic aldehydes. The intermediate propargylic alkoxides are trapped in situ with acetic anhydride, which are susceptible to a second nucleophilic displacement upon
本文描述了钛茂催化的多组分偶联。使用催化的钛茂,膦和锌粉,可以从相应的碘代炔烃生成乙炔锌,从而影响向芳香族醛的连续亲核加成。中间体炔丙基醇盐被原位捕获用乙酸酐,乙酸酐在用各种富含电子的物质处理后易发生第二次亲核取代,这些富含电子的物质包括乙炔化物,烯丙基硅烷,富电子芳族化合物,甲硅烷基烯醇醚和甲硅烷基烯酮缩醛。另外,使用环丙烷甲醛导致碘掺入导致开环产物。综上所述,这些结果构成了三组分偶联反应新模式的基础,该模式允许在单个合成操作中快速获得增值产品。