Ethyl 4-oxo-1-piperidinecarboxylate → 1-Carbethoxy-4-hydroxy-4-[2-(4-methylphenylsulfanyl)phenyl]piperidine

Participants

Reaction Conditions

Reaction Steps

2-(4-tolylsulfanyl)-phenyl bromide (6.98 g, 25 mmol) was dissolved in heptanes (40 mL) and dry tetrahydrofuran (4.1 mL) and after 1.5 hrs the reaction mixture was cooled down to 0° C. under an atmosphere of nitrogen. n-Butyllithium in heptanes 2.7 M (9.8 mL, 26.5 mmol) was added at 0° C. and after 45 min the reaction mixture was cooled to −15° C. A solution of N-carbethoxy-4-piperidone (3.8 mL, 25 mmol) in tetrahydrofuran (15 mL) was added maintaining the temperature below −15° C. Once the addition was complete the reaction was allowed to warm to room temperature. The reaction was quenched with a dilute hydrogen chloride solution. A sample from the organic phase shows a ratio of 1-carbethoxy-4-hydroxy-4-[2-(4-methylphenylsulfanyl)phenyl]piperidine to 1-methyl-4-phenylsulfanyl-benzene of 28:58.

Provenance & Evidence