A straightforward synthesis of [1,2-a][3′,2′-c]dipyrroloquinolines has been developed generating up to eight new σ-bonds and five new stereogenic centers in a simple and modular one-pot operation. Generally good to excellent yields and moderate to good stereoselectivities in favor of the all-cis stereoisomer were observed. A detailed investigation combining syntheticstudies, analytical measurements
[1,2- a ] [3',2'- c ]双吡咯并喹啉的简单合成方法已经开发出来,可以通过简单的模块化一锅操作生成多达八个新的σ键和五个新的立体异构中心。通常观察到良好至优异的产率和中等至良好的立体选择性,有利于全顺式立体异构体。结合合成研究,分析测量和理论计算进行了详细的研究,以阐明使用ESI和液束IR激光解吸质谱以及DFT计算的反应机理。此顺序转化的关键步骤包括路易斯酸催化的双(甲硅烷基)二烯二醇酯1的乙烯基类的Mukaiyama–Mannich反应。 并进行了Brønsted酸促进的Mannich–Pictet–Spengler反应级联反应,从而完成了目标化合物的二吡咯并喹啉核心的合成。
Diastereoselective synthesis of β-aminosulfones from the 1,2-addition to N-(para-methoxyphenyl) imines
作者:James C. Anderson、Ian B. Campbell、Sebastien Campos、Jonathan Shannon
DOI:10.1016/j.tetlet.2014.11.017
日期:2014.12
The base-promoted 1,2-addition of alkyl phenylsulfones to N-(para-methoxyphenyl) imines was investigated as a direct route to stereochemically defined beta-aminosulfones. Using (BuLi)-Bu-n as base, 2-(phenylsulfonyl)ethylbenzene was added to a range of N-(para-methoxyphenyl) imines to give B-aminosulfone products in high yields as single anti-diastereoisomers. Other less substituted alkyl phenylsulfones were not as successful. (C) 2014 The Authors. Published by Elsevier Ltd.
Brønsted Acid-Catalyzed, Enantioselective, Vinylogous Mannich Reaction of Vinylketene Silyl <i>N</i>,<i>O</i>-Acetals
作者:David S. Giera、Marcel Sickert、Christoph Schneider
DOI:10.1021/ol8017374
日期:2008.10.2
Vinylketene silyl N,O-acetals undergo chiral phosphoric acid-catalyzed, vinylogous Mukaiyama-Mannich reactions with imines and afford delta-amino-alpha,beta-unsaturated amides in typically good yields, complete gamma-regioselectivity, and up to 92% ee with catalyst loadings of as low as 1 mol %. The Mannich products can be readily manipulated to furnish valuable synthetic intermediates.
The Enantioselective, Brønsted Acid Catalyzed, Vinylogous Mannich Reaction