Isomerization of the Baylis-Hillman adducts using amberlyst-15 as a heterogeneous reusable catalyst:a simple and efficient stereoselective synthesis of (E)-cinnamyl alcohol derivatives

摘要

The Baylis-Hillman adducts,3-aryl-3-hydroxy-2-methylene-alkanoates and 3-aryl-3-hydroxy-2-methylene-alkane-nitriles have been efficiently isomerized to the corresponding (E)-cinnamyl alcohols by treatment of the adducts with Ac_2O in the presence of Amberlyst-15 followed by hydrolysis of the intermediate acetates with K_2CO_3/MeOH.The first step occurs under solvent-free conditions and the catalyst has been found to be reusable.