The tetrabutylammonium trifluoroacetate (TBATFA) catalyzed conversion
of alpha,beta-unsaturated carboxylic acids to the corresponding halide
s with N-halosuccinimides in dichloroethane is reported as the first e
xample of a metal-free catalytic version of the title reaction The met
hodology was further employed for a facile synthesis of piperine. (C)
1998 Published by Elsevier Science Ltd. All rights reserved.