Dimethyl Sulfoxide → (2S)-1-tert-butoxycarbonyl-2-phenylpiperidin-3-one

Participants

Reaction Conditions

Reaction Steps

To a cooled (-60° C.) solution of oxalyl chloride (0.68 ml, 7.8 mmol) in dichloromethane (17 ml) was added dimethyl sulfoxide (0.69 ml, 9.8 mmol) over 10 minutes before addition of (2S,3S)1-tert-butoxycarbonyl-3-hydroxy-2-phenylpiperidine (prepared by the method described in European Patent Specification number 0 528 495-A) in dichloromethane (7 ml). The solution was stirred at -60° C. for 20 minutes, warmed to -30° C. and triethylamine (2.5 ml) added. The solution was warmed to 0° C. then was washed with ice cold 10% aqueous citric acid solution (40 ml, twice) water and dried (MgSO4). The solution was evaporated to dryness to give the title compound and this was used immediately without further purification. 1H NMR (250 MHz, CDCl3) δ 7.5-7.3 (5H,m), 5.8 (1H, bs), 4.2 (1H, bs), 3.4 (1H, m), 2.6 (2H, m), 2.0 (2H, m), 1.54 (9H, s).

Provenance & Evidence