[N+:1]([C:4]1[CH:12]=[C:11]2[C:7]([CH:8]=[N:9][NH:10]2)=[CH:6][CH:5]=1)([O-:3])=[O:2].CS(O[CH2:18][CH2:19][CH2:20][O:21][CH3:22])(=O)=O.C([O-])([O-])=O.[K+].[K+].O>CC#N>[CH3:22][O:21][CH2:20][CH2:19][CH2:18][N:10]1[C:11]2[C:7](=[CH:6][CH:5]=[C:4]([N+:1]([O-:3])=[O:2])[CH:12]=2)[CH:8]=[N:9]1A mixture of 6-nitro-1H-indazole (50 g, 0.307 mol), 3-methoxypropyl methanesulfonate (54.3 g, 0.323 mol) and K2CO3 (127 g, 0.921 mol) in CH3CN (1.5 L) was heated at 60° C. overnight. Water (1 L) was added and the CH3CN was removed under reduced pressure and the aqueous residue was extracted with EtOAc (3×500 mL). The combined organic extracts were washed with brine, dried over Na2SO4, filtered and concentrated. The residue was purified by column chromatography on silica gel to give 1-(3-methoxypropyl)-6-nitro-1H-indazole (33 g, 46% yield). 1H NMR (400 MHz, CDCl3): δ8.47 (s, 1H), 8.13 (s, 1H), 8.01-7.99 (dd, J=8.8, 2.0 Hz, 1H), 7.83-7.81 (d, J=8.8 Hz, 1H), 4.61-4.57 (t, J=6.4 Hz, 2H), 3.29 (s, 3H), 3.26-3.23 (t, J=5.6 Hz, 2H), 2.23-2.17 (m, 2H).
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