Triethylamine → (S)-N-CBZ-valinol

Participants

Reaction Conditions

Reaction Steps

Benzyl chloroformate (91.0 g, 95% purity) was added dropwise over a period of 1 h to a precooled (0° C.) solution of L-valinol (50.0 g) and triethylamine (60.0 g) in chloroform (1500 ml). The reaction mixture was stirred for 1 h at 0° C. and then allowed to warm to,room temperature over 2 h. After the reaction mixture was evaporated, ethyl acetate (1500 ml) was added to the residue and the organic solution was washed (1N NaOH, brine), dried (MgSO4), and evaporated. The residue was purified by flash chromatography, using a stepwise gradient elution of ether:hexane (1:5) followed by ether, to give the alcohol (91.4 g) as a white waxy solid; TLC, Rf =0.23, hexane:ethanol (50:50).

Provenance & Evidence