ARTICLE TITLE: ''Fries like'' rearrangement: a novel and efficient method for the synthesis of 6-acyl-2(3H)-benzoxazolones and 6-acyl-2(3H)-benzothiazolones

ARTICLE AUTHOR: Ucar-H; VanDerpoorten-K; Depovere-P; Lesieur-D; Isa-M; Masereel-B; Delarge-J; Poupaert-JH

REPRINT AUTHOR: Ucar, H; UNIV CATHOLIQUE LOUVAIN; ECOLE PHARM, UNITE CHIM PHARMACEUT AND RADIOPHARM; B-1200 BRUSSELS; BELGIUM

SOURCE: TETRAHEDRON-. FEB 26 1998; 54 (9) : 1763-1772

ABSTRACT:

6-Acyl-2(3H)-benzoxazolone and 6-acyl-2(3H)-benzothiazolone derivatives have particularly interesting anti-inflammatory, antiepileptic, analgesic and antiviral properties. in this study, we report an original method of acylation on the 6-position of 2(3H)-benzoxazolone and 2(3H)-benzothiazolone which consists in a two-step procedure involving migration of the acyl group from the N-position to the 6-position of the heterocycle, at 165 degrees C and catalyzed by AlCl3. This new procedure was found to be more efficient with regard to the consumption of AlCl3 and the yield (76-90%) than other acylation methods previously described. (C) 1998 Elsevier Science Ltd. All rights reserved.