Ethanol → L-Proline 1,1-dimethylethyl ester

Participants

Reaction Steps

2 g (4.3 mmol) of N-[[N-(benzyloxycarbonyl)-L-phenylalanyl]methyl]-L-proline tert.butyl ester (prepared as described in Example 1) were dissolved in 25 ml of isopropanol, 25 ml of ethanol and 25 ml of methanol and the solution was stirred at room temperature for 4 hours in the presence of 0.4 g (10.7 mmol) of sodium borohydride. The solvent was removed by evaporation and the residue was partitioned between 50 ml of ethyl acetate and 25 ml of water. The organic phase was washed with saturated sodium chloride solution and dried over anhydrous sodium sulphate. The solvent was removedby evaporation and there were obtained 2 g of N-[3(S)-(benzyloxyformamido)-2(R and S)-hydroxy-4-phenylbutyl]-L-proline tert.butyl ester as a clear gum: Rf (System C): 0.68 and 0.57.

Provenance & Evidence