接近所有异构体:使用羧酸铑 (II) 催化剂可从邻位取代芳基叠氮化物中轻松获得一系列 α-、β- 和 δ-咔啉鎓离子(参见方案)。咔啉离子很容易被还原以提供色氨酸或去质子化以获取吡啶并吲哚。这种 [Rh II 2 ]-催化的 C H 键胺化用于合成 (±)-horsfiline 和新隐碱。esp=α,α,α',α'-四甲基-1,3-苯二丙酸酯。
“Base Effect” in the Auto-Tandem Palladium-Catalyzed Synthesis of Amino-Substituted 1-Methyl-1<i>H</i>-α-carbolines
作者:Ashok K. Yadav、Stefan Verbeeck、Steven Hostyn、Philippe Franck、Sergey Sergeyev、Bert U. W. Maes
DOI:10.1021/ol400064r
日期:2013.3.1
An auto-tandem Pd-catalyzed process consisting of an intramolecular direct arylation and an intermolecular Buchwald–Hartwig reaction for C-ring amino-substituted 1-methyl-1H-α-carboline synthesis has been developed. A mechanistic study of the direct arylationreaction revealed a rate effect of the inorganic base on the C–H activation step (“base effect”). The amines, reagents in the tandem protocol
已经开发了一种自动串联的Pd催化方法,该方法由分子内直接芳基化和分子间Buchwald-Hartwig反应组成,用于C环氨基取代的1-甲基-1 H -α-咔啉合成。直接芳基化反应的机理研究揭示了无机碱对CH活化步骤的速率影响(“碱效应”)。串联协议中的胺,试剂似乎对直接芳基化有相似的作用。
Highly efficient one-pot synthesis of D-ring chloro-substituted neocryptolepines via a condensation—Pd-catalyzed intramolecular direct arylation strategy
D-ring chloro-substituted neocryptolepines have been synthesized in excellent yield starting from 3-bromo-2-chloro-1-methylquinolinium triflate via a one-pot condensation Pd-catalyzed intramolecular direct arylation strategy involving chloroanilines. The 3-bromo-2-chloro-1-methylquinolinium triflate was obtained via methylation of commercial 3-bromo-2-chloroquinoline with methyl triflate. (C) 2010 Elsevier Ltd. All rights reserved.