Sodium hydride → Tert-butyl 10-[(4-methoxyphenyl)methyl]-9-oxo-8-phenyl-7-oxa-3,10-diazaspiro[5.5]undecane-3-carboxylate

Participants

Reaction Steps

To a suspension of tert-butyl 4-[[(2-chloro-2-phenyl-acetyl)-[(4-methoxyphenyl)methyl]amino]methyl]-4-hydroxy-piperidine-1-carboxylate (322 mg, 0.64 mmol) in DMF (3 mL) at 0° C. was added NaH (27 mg, 0.67 mmol). The reaction mixture was allowed to warm to room temperature overnight, then diluted with water (10 mL) and extracted with ethyl acetate (3×15 mL). The combined organic layers were washed with water (10 mL) and brine (10 mL), dried over MgSO4, filtered, and concentrated in vacuo. The crude product was purified by silica gel column chromatography using 0-40% EtOAc/DCM to give tert-butyl 10-[(4-methoxyphenyl)methyl]-9-oxo-8-phenyl-7-oxa-3,10-diazaspiro[5.5]undecane-3-carboxylate (215 mg, 72%) as a colorless oil. ESI-MS m/z calc. 502.2. found 503.5 (M+1)+; Retention time: 1.90 minutes (3 min run).

Provenance & Evidence