%0 Journal Article
%T Amine and Titanium (IV) Chloride, Boron (III) Chloride or Zirconium (IV) Chloride-Promoted Baylis-Hillman Reactions
%A Min Shi
%A Jian-Kang Jiang
%A Shi-Cong Cui
%J Molecules
%D 2001
%I MDPI AG
%R 10.3390/61100852
%X The Baylis-Hillman reactions of various aryl aldehydes with methyl vinyl ketone at temperatures below -20oC using Lewis acids such as titanium (IV) chloride, boron (III) chloride or zirconium (IV) chloride in the presence of a catalytic amount of selected amines used as a Lewis bases afford the chlorinated compounds 1 as the major product in very high yields. Acrylonitrile can also undergo the same reaction to give the corresponding chlorinated product in moderate yield. A plausible reaction mechanism is proposed. However, if the reaction was carried out at room temperature (ca. 20oC), then the Z-configuration of the elimination product 3, derived from 1, was formed as the major product.
%K Titanium (IV) chloride
%K boron (III) chloride
%K zirconium (IV) chloride
%K Bayliss-Hillman reaction
%K halogenation
%K Lewis base
%K amine
%U http://www.mdpi.com/1420-3049/6/11/852