The reaction of 2,2-difluoro-2-(4-isobutylphenyl)acetic acid (I) with oxalyl chloride in dichloromethane gives the corresponding acyl chloride (II), which is then treated with 6-methyl-2,4-bis(methylsulfanyl)pyridine-3-amine (III) and 4-(dimethylamino)pyridine (DMAP) in the same solvent.