Methanol → HCID 21955386, compound

Participants

Reaction Steps

Borane-tetrahydrofuran complex (1.0M in tetrahydrofuran, 60 mL, 60 mmol) was added to a suspension of α-ethyl 4-carboxy-1-(phenylmethyl)-4-piperidineacetate hydrochloride (Helv. Chim. Acta 1972, 55, 2432–2438, 10.24 g, 30 mmol) in tetrahydrofuran (150 mL) and the mixture was stirred at room temperature for 3 days. Further borane-tetrahydrofuran complex (1.0M in tetrahydrofuran, 60 mL, 60 mmol) was added and the mixture was stirred at room temperature for 1 day. Methanol (20 mL) was added and the solvent was evaporated under reduced pressure. Methanol (200 mL) was added and the solvent was evaporated under reduced pressure. Methanol (200 mL) was added and the solvent was evaporated under reduced pressure. Hydrochloric acid (2M, 200 mL) was added and the mixture was heated under reflux for 4 hours. The mixture was cooled. Ether (200 mL) was added and the layers were separated. The organic layer was extracted with hydrochloric acid (2M, 2×100 mL) and the combined aqueous fractions were washed with ether (2×100 mL), adjusted to pH 10 with saturated aqueous potassium carbonate and extracted with dichloromethane (3×100 mL). The combined organic fractions were dried (MgSO4) and the solvent was evaporated under reduced pressure. The residue was purified by flash column chromatography on silica gel, eluting with CH2Cl2/MeOH/NH3(aq.) (96:4:0.4), to give the title compound (3.4 g, 46%). m/z (ES+) 246 (M+1).

Provenance & Evidence