An acid-promoted novel skeletal rearrangement initiated by intramolecular ipso-Friedel–Crafts-type addition to 3-alkylidene indolenium cations
作者:Takuya Yokosaka、Tetsuhiro Nemoto、Yasumasa Hamada
DOI:10.1039/c2cc31699d
日期:——
An acid-promoted novel skeletal rearrangement is described. Using trifluoroacetic acid as the acid promoter, an intramolecular ipso-Friedel-Crafts-type addition of phenols to 3-alkylidene indolenium cations, formation of iminium cations through rearomatization of the spirocyclohexadienone units, and intramolecular Pictet-Spengler reaction proceeded sequentially, producing tricyclic indole derivatives
描述了一种酸促进的新型骨骼重排。使用三氟乙酸作为酸促进剂,将分子内的ipso-Friedel-Crafts型酚添加到3-亚烷基吲哚阳离子中,通过螺环己二烯酮单元的重新芳构化形成亚胺阳离子,并依次进行分子内的Pictet-Spengler反应,从而生成三环吲哚衍生品。