反应详情

To a mixture of 4-(3-methylphenyl)-4-hydroxypiperidine hydrochloride (457 mg, 2.00 mmol), the aldehyde from step E (508 mg, 2.41 mmol), and 3A molecular sieves (2.0 g) in methanol (20 ml) was added sodium cyanoborohydride (2.20 ml of a 1M solution in THF, 2.20 mmol). The pH was adjusted to 5 by addition of acetic acid and the reaction stirred under argon for 48 hrs at room temperature. The solids were removed by filtration and the filtrate partitioned between EtOAc and saturated NaHCO3 solution, the organic extracts were dried (MgSO4), and the solvent evaporated in vacuo. The residue was purified by chromatography (SiO2, gradient elution, 5 to 7% MeOH in methylene chloride. The residue was converted to the corresponding hydrochloride salt by its treatment with a solution of two equivalents of HCl in aqueous acetonitrile and subsequent evaporation of solvents in vacuo.

1. customThe solids were removed by filtration
2. customthe filtrate partitioned between EtOAc and saturated NaHCO3 solution
3. dry with materialthe organic extracts were dried (MgSO4)
4. customthe solvent evaporated in vacuo
5. customThe residue was purified by chromatography (
6. washSiO2, gradient elution, 5 to 7% MeOH in methylene chloride