Lithium Hydroxide → 3-iodo-1-(tetrahydro-2H-pyran-2-yl)-1H-indazole-5-carboxylic acid
Reaction equation
[I:1][C:2]1[C:10]2[C:5](=[CH:6][CH:7]=[C:8]([C:11]([O:13]C)=[O:12])[CH:9]=2)[N:4]([CH:15]2[CH2:20][CH2:19][CH2:18][CH2:17][O:16]2)[N:3]=1.[Li+].[OH-]>C1COCC1.CO>[I:1][C:2]1[C:10]2[C:5](=[CH:6][CH:7]=[C:8]([C:11]([OH:13])=[O:12])[CH:9]=2)[N:4]([CH:15]2[CH2:20][CH2:19][CH2:18][CH2:17][O:16]2)[N:3]=1Participants
4
Procedure
To a solution of methyl 3-iodo-1-(tetrahydro-2H-pyran-2-yl)-1H-indazole-5-carboxylate ((5.0 g, 12.9 mmol) in THF: MeOH (70:30) (50 mL) was added LiOH (3.10 g, 129.0 mmol) in one lot and the reaction was stirred at RT for 12 h. The solvent were removed in vacuo and the residue was diluted with water and quenched with 1N HCl (50 mL) to obtain off white precipitate. The suspension was stirred for 10 min and filtered and dried to give 3-iodo-1-(tetrahydro-2H-pyran-2-yl)-1H-indazole-5-carboxylic acid (4.2 g, 87%) as an off white solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 13.09 (s, 1H), 8.03-8.06 (m, 2H), 7.84-7.86 (m, 1H), 5.93 (dd, 1 H, J=9.7, 2.3 Hz), 3.90 (d, 1 H, J=11.9 Hz), 3.74-3.76 (m, 1H), 2.35-2.41 (m, 1H), 1.97-2.00 (m, 2H), 1.69-1.80 (m, 1H), 1.41-1.58 (m, 2H).