The bromination of 2',6'-difluoroacetophenone (I) using CuBr2 afforded bromoketone (II). Addition of cyanamide to 4-isothiocyanato-benzenesulfonamide (III) in the presence of potassium tert-butoxide generated the intermediate N-cyano isothiourea (IV). Subsequent condensation of (IV) with bromoketone (II) produced the target thiazole derivative.
Treatment of 1-(4-aminophenyl)-4-methylpiperazine (I) with thiophosgene and Na2CO3 afforded isothiocyanate (II). Subsequent condensation of (II) with cyanamide in the presence of potassium tert-butoxide, followed by reaction of the resulting intermediate (IV) with 2-chloro-2',6'-difluoroacetophenone (V) produced the title aminothiazole.