[C:1]([N:4]1[C:12]2[C:7](=[CH:8][CH:9]=[C:10]([F:13])[CH:11]=2)[C:6]([CH3:14])=[N:5]1)(=[O:3])[CH3:2].C1C(=O)N([Br:22])C(=O)C1.C(OOC(=O)C1C=CC=CC=1)(=O)C1C=CC=CC=1>C(Cl)(Cl)(Cl)Cl>[C:1]([N:4]1[C:12]2[C:7](=[CH:8][CH:9]=[C:10]([F:13])[CH:11]=2)[C:6]([CH2:14][Br:22])=[N:5]1)(=[O:3])[CH3:2]1-Acetyl-6-fluoro-3-methyl-1H-indazole (5.77 g, 33.1 mmol) in CCl4 (100 mL) was treated with NBS (3.64 g, 20 mmol) and benzoyl peroxide (0.388 g, 1.6 mmol) and the mixture was heated at 70° C. for 6 h. The mixture was concentrated and the residue quickly filtered through a plug of flash silica eluting with 2%→7% EtOAc in hexane to give the crude title compound (2.97 g, 65%) contaminated with traces of dibromide and starting material. This was conveniently used directly in subsequent reactions without further purification.
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