Aldehydes vs Aldimines. Unprecedented Aldimine-Selective Nucleophilic Additions in the Coexistence of Aldehydes Using a Lanthanide Salt as a Lewis Acid Catalyst
作者:Shū Kobayashi、Satoshi Nagayama
DOI:10.1021/ja971153y
日期:1997.10.1
It is well-recognized that aldimines are less reactive than aldehydes toward nucleophilic additions. In this paper, an unprecedented change in the reactivity is described: preferential reactions of aldimines over aldehydes in nucleophilic additions using a lanthanide salt as a Lewis acid catalyst. In the presence of a catalytic amount of ytterbium triflate (Yb(OTf)3), only aldimines reacted with silyl
众所周知,醛亚胺对亲核加成的反应性低于醛。在本文中,描述了一种前所未有的反应性变化:在亲核加成中使用镧系元素盐作为路易斯酸催化剂,醛亚胺优先于醛反应。在催化量的三氟甲磺酸镱 (Yb(OTf)3) 存在下,只有醛亚胺与甲硅烷基烯醇醚、烯酮甲硅烷基缩醛、烯丙基三丁基锡烷或氰基三甲基硅烷反应,以高产率提供相应的加合物,即使在醛共存的情况下也是如此。13C NMR 分析表明选择性形成醛亚胺-Yb(OTf)3 复合物而不是醛-Yb(OTf)3 复合物。虽然这份报告证明了路易斯酸在有机合成中的有效利用,