Synthesis of substituted 3-methylene-2-pyridones from Baylis–Hillman derivatives and its application for the generation of 2-pyridone substituted spiroisoxazolines
作者:Virender Singh、Gaya P. Yadav、Prakas R. Maulik、Sanjay Batra
DOI:10.1016/j.tet.2008.01.074
日期:2008.3
The synthesis of substituted 3-methylene-2-pyridones via S(N)2 displacement reaction of nucleophiles bearing a keto group on the acetyl derivative of Baylis-Hillman adducts of acrylonitrile followed by TFA/H2SO4-mediated intramolecular cyclization is described. The utility of these pyridone derivatives for the synthesis of new spiroisoxazolines in highly regio- and stereo-selective fashion is also illustrated. The structure of the spiroisoxazolines has been secured via X-ray crystallographic analysis. (C) 2008 Elsevier Ltd. All rights reserved.
An alternate approach to quinoline architecture via Baylis–Hillman chemistry: SnCl2-mediated tandem reaction toward synthesis of 4-(substituted vinyl)-quinolines
作者:Sudharshan Madapa、Virender Singh、Sanjay Batra
DOI:10.1016/j.tet.2006.06.098
日期:2006.9
acetyl derivatives of the Baylis–Hillman adducts obtained from 2-nitrobenzaldehydes and the carbonyl group containing carbon nucleophiles is described. Treatment of these compounds with SnCl2, triggers a tandem reaction wherein reduction of the nitro group is followed by a remarkably regioselective intramolecularcyclization and subsequent dehydrogenation to afford 4-(substituted vinyl)-quinolines.
描述了从2-硝基苯甲醛获得的Baylis-Hillman加合物的乙酰基衍生物与含羰基的碳亲核试剂之间的S N 2亲核取代反应产物中稠密取代的喹啉的另一种方法。用SnCl 2处理这些化合物触发串联反应,其中硝基的还原,随后是区域选择性的分子内环化反应,然后脱氢,得到4-(取代的乙烯基)-喹啉。