Is metal necessary in the Hunsdiecker-Borodin reaction?

Article abstract of DOI:10.1016/S0040-4039(97)10639-6

The tetrabutylammonium trifluoroacetate (TBATFA) catalyzed conversion of α,β-unsaturated carboxylic acids to the corresponding halides with N-halosuccinimides in dichloroethane is reported as the first example of a metal-free catalytic version of the title reaction. The methodology was further employed for a facile synthesis of piperine.