Cesium carbonate → Tert-butyl 4-(5-chloro-3-(methoxycarbonyl)-2-methylphenoxy)piperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of methyl 5-chloro-3-hydroxy-2-methylbenzoate (1.25 g, 6.23 mmol), tert-butyl 4-((methylsulfonyl)oxy)piperidine-1-carboxylate (3.66 g, 13.08 mmol) and cesium carbonate (5.08 g, 15.58 mmol) in DMF (25 mL) was heated at 75° C. for 18 h. The reaction was allowed to cool to ambient temperature and poured into ice/water (200 mL) with stirring. The mixture was extracted with EtOAc (3×100 mL), dried over magnesium sulfate, and concentrated in vacuo. The light yellow residue was purified by flash chromatography (5-50% EtOAc/hexanes) to give tert-butyl 4-(5-chloro-3-(methoxycarbonyl)-2-methylphenoxy)piperidine-1-carboxylate (1.95 g, 5.08 mmol, 82% yield) as a solid. 1H NMR (DMSO-d6) δ 7.37 (d, J=2.0 Hz, 1H), 7.31 (d, J=2.0 Hz, 1H), 4.71 (dt, J=7.4, 3.8 Hz, 1H), 3.83 (s, 3H), 3.54-3.63 (m, 2H), 3.22-3.31 (m, 2H), 2.28 (s, 3H), 1.83-1.93 (m, 2H), 1.51-1.63 (m, 2H), 1.41 (s, 9H).

Provenance & Evidence