Acylation reaction of m-cresol with 2-chlorobenzoic acid in PPA occurred through a prior esterification, followed by a Fries rearrangement of ester (3) to give benzophenones 4—7. Ester 3 undergoes the Fries rearrangement in PPA, giving benzophenones 4—7 in about the same yield as can be obtained by direct acylation reaction of m-cresol with 2- chlorobenzoic acid. The benzophenone 5 is not stable in PPA and decomposed to ...