Dichloromethane → HCID 13923698, compound

Participants

Reaction Steps

At -14° with the exclusion of moisture, 340 ml of 1,5-diazabicyclo[5.4.0]undec-5-ene in 1 ml of tetrahydrofuran are added to a solution of 486 mg (1.1 mmol) of (2S,3R)-N-p-methoxybenzyl-N-tert.-butylsulphonylmethyl-2-bromo-3-hydroxybutyramide in 8 ml of tetrahydrofuran. The solution is stirred at room temperature for 75 minutes. After the addition of methylene chloride, the organic phase is extracted by shaking with 15% aqueous citric acid solution and 8% aqueous sodium bicarbonate solution. The organic phase is dried over sodium sulphate and concentrated by evaporation under reduced pressure. After chromatography of the residue over silica gel with toluene/ethyl acetate (4:1), the title compound is obtained in the form of a colourless, viscous oil. Rf (toluene/ethyl acetate 1:1): 0.29; [α]=+45± 1° (1.065% in CHCl3). The 1H-NMR spectrum (400 MHz in CDCl3) points to the existence of two rotamers in a ratio of 1:2.8.

Provenance & Evidence