A Facile Synthesis of 1,1-Disubstituted 1,2,3,4-Tetrahydro-b-carbolines via Trifluoroacetic Acid Catalyzed Pictet- Spengler Reaction Using Titanium(IV) Isopropoxide as an Imination Reagent
摘要:
A synthesis of 1,1-disubstitued 1,2,3,4-tetrahydro-beta-carbolines (13) was achieved in a highly effective manner via the trifluoroacetic acid catalyzed Pictet-Spengler reaction of the keto imines (9) prepared from tryptamine (8) with acyclic and cyclic ketones using titanium(IV) isopropoxide as the imination reagent under one pot procedure. This reaction provides a convenient and general method for preparing various 1,2,3,4-tetrahydro-beta-carbolines derivatives.
Two‐in‐One Strategy for Palladium‐Catalyzed C−H Functionalization in Water
作者:Huiying Zeng、Zemin Wang、Chao‐Jun Li
DOI:10.1002/anie.201813391
日期:2019.2.25
Transition metal catalyzedC−Hfunctionalizations have been developed as powerful methods for C−C bond formations. Directing groups, removable directing groups, traceless directing groups, and transient directing groups (TDGs) have been successfully used to improve the reaction efficiencies. For the development of greener and more sustainable methods, C−Hfunctionalization using a TDG that also serves
The indole C5-selective bromination of indolo[2,3-a]quinolizidine alkaloids by adding nearly equimolar amounts of Br3 ⋅ PyH and HCl in MeOH is disclosed. The resulting reaction plausibly proceeds through an indoline intermediate by the nucleophilic addition of MeOH to the C3-brominated indolenine intermediate. These simple, mild, and metal-free conditions are suitable for late-stage chemical conversions
公开了通过在MeOH中添加几乎等摩尔量的Br 3 ·PyH和HCl来对吲哚并[2,3- a ]喹啉西啶生物碱进行吲哚C5选择性溴化。通过将MeOH亲核加成至C3-溴化吲哚啉中间体,所得反应似乎通过二氢吲哚中间体进行。这些简单、温和且不含金属的条件适用于全合成和药物化学中的后期化学转化。
The synthesis of 1,1-disubstituted tetrahydro-β-carbolines induced by iodine
作者:Y. Lingam、D. Muralimohan Rao、Dipal R. Bhowmik、Pachore Sharad Santu、K. Raghavendra Rao、Aminul Islam
DOI:10.1016/j.tetlet.2007.06.099
日期:2007.10
A mild access to 1,1-disubstituted tetrahydro-beta-carbolines is described. Tryptamine is subjected to Pictet-Spengler cyclization with various ketones using iodine. (C) 2007 Elsevier Ltd. All rights reserved.
Application of chlorotrimethylsilane in Pictet–Spengler reaction
作者:Sergey V. Ryabukhin、Dmitriy M. Panov、Andrey S. Plaskon、Andrey A. Tolmachev、Radomyr V. Smaliy
DOI:10.1007/s00706-012-0804-7
日期:2012.11
Chlorotrimethylsilane has been found to be an efficient condensing agent in the Pictet-Spengler reaction, affording an extremely straightforward synthetic route to tetrahydro-beta-carboline derivatives and their analogs. The applicability of the method has been studied, and a representative library of structurally diverse products has been created..