F[CH:2]1[CH:8](N)[CH2:7][CH2:6][CH2:5][N:4]([C:10]2[NH:14][N:13]=[CH:12][C:11]=2[N+:15]([O-:17])=[O:16])C1.ClC1NN=CC=1[N+]([O-])=[O:25].O.Cl.N1CCC(=O)CC1.[F-].[K+]>CS(C)=O>[N+:15]([C:11]1[CH:12]=[N:13][NH:14][C:10]=1[N:4]1[CH2:5][CH2:6][C:7](=[O:25])[CH2:8][CH2:2]1)([O-:17])=[O:16]FIG. 10 shows an exemplary synthesis of 3-fluoro-1-(4-nitro-1H-pyrazol-5-yl)azepan-4-amine 52 from 5-chloro-4-nitro-1H-pyrazole 3. Heating 3 with piperidin-4-one hydrochloride hydrate and potassium fluoride in a suitable solvent such as dimethylsulfoxide or using methods described in the literature gives 1-(4-nitro-1H-pyrazol-5-yl)piperidin-4-one 46. Heating 46 with trimethylsilyl chloride and triethylamine in a suitable solvent such as DMF or using methods described in the literature gives 1-(4-nitro-1H-pyrazol-5-yl)-4-(trimethylsilyloxy)-1,2,3,6-tetrahydropyridine 47. Fluorination of 47 using SelectFluor® in acetonitrile at a suitable temperature or using methods described in the literature gives 3-fluoro-1-(4-nitro-1H-pyrazol-5-yl)piperidin-4-one 48. Ring expansion of 48 to ethyl 6-fluoro-1-(4-nitro-1H-pyrazol-5-yl)-5-oxoazepane-4-carboxylate 49 may be achieved using ethyl diazoacetate and boron trifluoride diethyl etherate in a suitable solvent such as dichloromethane at suitable temperatures or using methods described in the literature. Decarboxylation of 49 by heating with hydrochloric acid at a suitable temperature or by methods described in the literature to give 3-fluoro-1-(4-nitro-1H-pyrazol-5-yl)azepan-4-one 50. Reductive amination of 50 by methods described in the literature gives 3-fluoro-1-(4-nitro-1H-pyrazol-5-yl)azepan-4-amine 51. The amine of 51 can be protected with a suitable protecting group such as trifluoroacetamide using trifluoroacetic anhydride with diisopropylethylamine in a suitable solvent such as dichloromethane, or using other methods described in the literature, to give amine-protected 52.
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