The condensation of 2-(4-tetrahydropyranyl)acetic acid (I) with 4-(4-chlorophenoxy)thiophenol (II) in piperidine at 100 C gives 2-[4-[4-(4-chlorophenoxy)phenylsulfanyl]tetrahydropyran-4-yl]acetic acid (III), which is treated with O-tert-butylhydroxylamine (IV) and 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide in dichloromethane yielding th N-(tert-butoxy)amide (V). The deprotection of (V) with trifluoroacetic acid affords the acetohydroxamic acid (VI), which is finally oxidized with oxone to the target sulfone.