[Br:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=1[S:8][C:9]1[CH:17]=[CH:16][C:15]([N+:18]([O-:20])=[O:19])=[CH:14][C:10]=1[C:11]([OH:13])=O>CS(O)(=O)=O>[Br:1][C:2]1[CH:7]=[CH:6][CH:5]=[C:4]2[C:3]=1[S:8][C:9]1[CH:17]=[CH:16][C:15]([N+:18]([O-:20])=[O:19])=[CH:14][C:10]=1[C:11]2=[O:13]2-(2-Bromo-phenylsulfanyl)-5-nitro-benzoic acid (34 g, 96 mmol) was suspended in methanesulphonic acid (400 ml) and heated at 150° C. The crude mixture was slowly poured onto ice with vigorous stirring and the precipitate formed was filtered. The solid was suspended into water (50 ml) quenched to pH 7-8 with conc. ammonia solution and filtered. The yellow/lime colored solid was dried under vacuum at 50° C. to give the crude title compound, which was used without any further purification (23.09 g, 72%).
Wird geladen…