Boron tribromide → 2-(6-((6S)-6-((S)-1-hydroxyethyl)-2,2-dimethylpiperidin-4-yloxy)pyridazin-3-yl)-5-(1H-pyrazol-1-yl)phenol

Participants

Reaction Steps

To a solution of 3-((6S)-6-((S)-1-(tert-butyldimethylsilyloxy)ethyl)-2,2-dimethylpiperidin-4-yloxy)-6-(2-methoxy-4-(1H-pyrazol-1-yl)phenyl)pyridazine (56 mg, 0.1 mmol) in CH2Cl2 (2 mL) was added BBr3 (1 M in heptane, 0.13 mL, 0.13 mmol) dropwise at 0° C. The mixture was stirred overnight. The reaction mixture was quenched with water and then basicifed with saturated NaHCO3 solution. The organic layer was extracted with 10% MeOH in dichloromethane (10 mL×3). The combined extracts were dried over Na2SO4 and concentrated in vacuo. Purification by HPLC gave 12 mg (28%) of 2-(6-((6S)-6-((S)-1-hydroxyethyl)-2,2-dimethylpiperidin-4-yloxy)pyridazin-3-yl)-5-(1H-pyrazol-1-yl)phenol: LCMS Rt=0.52 min (LCMS method Q); MS=410.3 (M+1); 1H NMR (400 MHz, METHANOL-d4) δ 8.23 (d, J=9.6 Hz, 1H), 8.19 (d, J=2.0 Hz, 1H), 7.86 (d, J=8.6 Hz, 1H), 7.65 (d, J=2.0 Hz, 1H), 7.32-7.25 (m, 2H), 7.22 (d, J=9.6 Hz, 1H), 6.47-6.43 (m, 1H), 5.59-5.66 (m, 1H), 3.68-3.77 (m, 1H), 3.02-3.11 (m, 1H), 2.03-2.15 (m, 2H), 1.49-1.59 (m, 2H), 1.24 (s, 3H), 1.11 (d, J=6.4 Hz, 3H), 1.10 (s, 3H).

Provenance & Evidence