A Cascade Approach to Captodative Trifluoromethylated Enamines or Vinylogous Guanidinium Salts: Aromatic Substituents as Switches of Reaction Direction
作者:Alexander Yu. Rulev、Vasiliy M. Muzalevskiy、Evgeniy V. Kondrashov、Igor A. Ushakov、Aleksey V. Shastin、Elizabeth S. Balenkova、Günter Haufe、Valentine G. Nenajdenko
DOI:10.1002/ejoc.200900926
日期:2010.1
β-Halo-β-(trifluoromethyl)styrenes readily react with a variety of nitrogen nucleophiles bearing primary amino groups to afford either the captodative trifluoromethylated enamines or vinylogous guanidinium salts in a selective fashion depending on the electronic natures of the aromatic substituents.
Mechanistic study of multi-step nucleophilic substitution for trifluoromethylated styrenes
作者:Alexander Yu. Rulev、Igor A. Ushakov、Evgeniy V. Kondrashov、Vasiliy M. Muzalevskiy、Aleksey V. Shastin、Valentine G. Nenajdenko
DOI:10.1016/j.jfluchem.2011.07.015
日期:2011.11
nucleophiles with β-halogen-β-trifluoromethylstyrenes have been studied by 19F and 1H NMR monitoring and quantum-chemical calculations. In contrast to the mechanism proposed earlier for nucleophilic vinylic substitution of captodative carbonyl-bearing haloalkenes, this reaction proceeds via either E–Ad or Ad–E sequence depending on the nature of aromatic substituents of the parent styrenes.
通过19 F和1 H NMR监测以及量子化学计算,研究了氮亲核试剂与β-卤素-β-三氟甲基苯乙烯反应的关键步骤。与早先提出的对带有羰基的羰基卤代烯烃进行亲核乙烯基取代的机理相反,根据母体苯乙烯的芳族取代基的性质,该反应通过E-Ad或Ad-E序列进行。