[N+:1]([C:4]1[CH:5]=[CH:6][C:7]2[S:11]N=N[C:8]=2[CH:12]=1)([O-:3])=[O:2].[C:13]1([N:19]=[C:20]=[S:21])[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1>>[N+:1]([C:4]1[CH:5]=[CH:6][C:7]2[S:11][C:20](=[N:19][C:13]3[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=3)[S:21][C:8]=2[CH:12]=1)([O-:3])=[O:2]A solution of 5-nitro-1,2,3-benzothiadiazole (4.6 g) in 50 ml of phenylisothiocyanate is heated at 220° C under an inert atmosphere until the evolution of nitrogen ceases (approximately 3 hours). The excess phenylisothiocyanate is removed in vacuo and the resultant residue chromatographed on 1000 ml of silica gel eluting with methylene chloride/pentane (1:4). The fractions containing the desired product are combined and concentrated in vacuo. The resultant solid is recrystallized from cyclohexane to yield 2.1 g of the title compound, melting point 136°-138° C.
Wird geladen…