[Br:1][C:2]1[CH:3]=[CH:4][C:5](F)=[C:6](/[CH:8]=[N:9]/[NH:10][C:11]2[CH:16]=[CH:15][C:14]([F:17])=[CH:13][CH:12]=2)[CH:7]=1.C(=O)([O-])[O-].[Cs+].[Cs+].CS(C)=O>O>[Br:1][C:2]1[CH:7]=[C:6]2[C:5](=[CH:4][CH:3]=1)[N:10]([C:11]1[CH:16]=[CH:15][C:14]([F:17])=[CH:13][CH:12]=1)[N:9]=[CH:8]2A 30 mL microwave vial was charged with 3.00 g (9.642 mmol) of N-[1-(5-bromo-2-fluorophenyl)meth-(E)-ylidene]-N′-(4-fluorophenyl)hydrazine and 3.14 g (9.64 mmol) of cesium carbonate and 10 mL of DMSO and sealed. The mixture was warmed at 220° C. in the microwave for 15 minutes cooled and opened at room temperature. The mixture was diluted with 10 mL of water and extracted with 20 mL of EtOAc. The organic layer was washed with brine, dried over sodium sulfate, filtered and concentrated in vacuo. The residue was absorbed onto silica gel and passed through a silica pad and eluted with 50% EtOAc-hexanes. The partially purified material from the pad was triturated with MeOH, collected by filtration, and dried to afford 2.8 g (99.7%) of 5-bromo-1-(4-fluorophenyl)-1H-indazole. MS m/z 279.11 (MH+).
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