Diflunisal was prepared from 2,4 difluoroaniline via biphenylation,Friedel Crafts acylation,Baeyer Villiger rearrangement,hydrolysis and carboxylation. The overall yield was 38.4%.

• 以 2 ；4-二氟苯胺为起始原料 ；经联苯化作用、Friedel-Crafts酰化反应、Baeyer-Villiger重排、水解和羧基化作用 5步反应制得 2′；4′-二氟 -4-羟基 -(1 ；1′-联苯 ) -3 -羧酸 ；总收率可达 3 8.；4%25