Triethylamine → n-Cbz-3-hydroxypiperidine

Participants

Reaction Steps

Benzylchloroformate (15 ml) was added dropwise to a stirred suspension of 3-hydroxypiperidine hydrochloride (13,7 g) and triethylamine (30 ml) in dichloromethane (150 ml),maintaining the temperature below 15° C. throughout. Stirring was continued for three hours,then the solution was washed with water (4×100 ml) and saturated aqueous sodium chloride (100 ml),dried (PS paper) and concentrated. The residual oil was dissolved in ether (300 ml),washed with dilute hydrochloric acid (2×100 ml) and water (100 ml),dried (PS paper) and concentrated. The residue was purified by flash column chromatography,eluting first with hexane/ether (1: 1) then ether to give 1-benzyloxycarbonylpiperidine-3-ol (7.1 g) as a colourless oil. NMR (d6DMSO) δ1.2-1.4(2H,m); 1.6-1.9(1 H,m +1 H,m); 2.8(1H,br s); 2.95(1 H,m); 3.45(1 H,m); 3.65(1H,brd); 3.8(1H,dd); 4.85(1H,d); 5.1(2H,s); 7.3(5H,m); m/e 236(M+H)+.

Provenance & Evidence