反应详情

To a stirred solution of (±)-cis-4-[6-butyl-5-(4-cyclohexyloxy-phenyl)-pyridazin-3-yloxymethyl]-piperidin-3-ol dihydrochloride (Example 35, ˜0.2 mmol) in dichloromethane (2.0 mL), was added formaldehyde solution in water (37%, 2.0 mmol, 0.2 mL), and 1 drop of acetic acid. Then sodium triacetoxyborohydride (2.0 mmol, 424 mg) was added. The mixture was stirred at room temperature for 0.5 hour, then condensed, worked up and the solvent was removed in vacuo. The residue was purified by silica gel chromatography (DCM to DCM+10% 2N ammonia in MeOH) to give a colorless sticky solid, which was dissolved in DCM (1.0 mL), 2N HCl in ether (1.0 mL) was added, condensed, triturated with hexanes to provide title compound (51 mg). LCMS: m/z 455 [M+1]. 1H NMR (400 MHz, CD3OD) δ 7.48 (1H, s), 7.39-7.43 (2H, m), 7.08-7.12 (2H, m), 4.52-4.59 (1H, m), 4.39-4.48 (2H, m), 4.27 (1H, bs), 3.38-3.54 (2H, m), 3.02-3.26 (4H, m), 2.85 (3H, s), 2.25-2.37 (1H, m), 1.78-2.07 (6H, m), 1.20-1.43 (10H, m), 0.81 (3H, t).

1. customcondensed
2. customthe solvent was removed in vacuo
3. customThe residue was purified by silica gel chromatography (DCM to DCM+10% 2N ammonia in MeOH)
4. customto give a colorless sticky solid, which
5. customcondensed
6. customtriturated with hexanes