Extending Pummerer Reaction Chemistry. Development of a Strategy for the Regio- and Stereoselective Oxidative Cyclization of 3-(ω-Nucleophile)-Tethered Indoles
作者:Ken S. Feldman、Daniela Boneva Vidulova、Andrew G. Karatjas
DOI:10.1021/jo050896w
日期:2005.8.1
substrate, for steering nucleophilic addition to C(3) of the indole. Extension of this transformation from carboxylate nucleophiles to carbon analogues such as allylsilane, silyl enol ether, and silyl ketene iminal bearing substrates led to the formation of spirocyclic oxindole derivatives in good yields with complete regioselectivity for C(3) cyclization and with good diastereoselectivity where relevant.
非对映异构体β-甲硅烷氧基色氨酸衍生物的溴化环化反应根据甲硅烷氧基取代基的相对立体化学,以不同的区域化学(C(2)或C(3)加成)进行。缺乏C(2)与C(3)的区域化学可预测性导致了新方法的发展,该方法的特征是在吲哚C(2)亚砜或硫化物底物上进行Pummerer型化学反应,以控制向C(3)的亲核加成的吲哚。从羧酸盐亲核体到碳类似物(如烯丙基硅烷,甲硅烷基烯醇醚和甲硅烷基烯酮亚氨基)的底物的这种转化的扩展导致螺环肟吲哚衍生物的形成具有良好的产率,对C(3)环化具有完全的区域选择性,并在相关时具有良好的非对映选择性。