反应详情

150 g of the 98:2 mixture of the (4S,5S) and (4S,5R) isomers of 4-benzyl-2-oxo-oxazolidine-5-carboxylic acid methyl ester were added at 15°-20° over a period of 1.5 hours to a stirred solution of 20.8 g of sodium borohydride in 360 ml of ethanol and then stirred for a further 2 hours. The suspension was combined at 20° with 540 ml of water and the pH value adjusted to 7 with 165 ml of 3N hydrochloric acid. The suspension was stirred at room temperature for 2.5 hours, left to stand for 18 hours at 4° and then filtered. The residue was washed with water and dried and yielded 111.6 g (84%) of 99% (4S,5S)-4-benzyl-5-hydroxymethyl-oxazolidin-2-one, melting point 167.3°-168.9°, [α]D20 : -79.4° (1% in methanol).

1. stirringThe suspension was stirred at room temperature for 2.5 hours
2. waitleft
3. waitto stand for 18 hours at 4°
4. filtrationfiltered
5. washThe residue was washed with water
6. customdried