反应详情

温度

5 °C

N-tert-butoxycarbonyl-3(S)-amino-2(R)-hydroxy-4-phenyl-butyric acid methyl ester 340.4 kg was reduced with sodium borohydride by the same way as described in Reference Example 3, to obtain the crude N-tert-butoxycarbonyl-3(S)-amino-2(R)-hydroxy-4-phenyl-1-butanol, which was dissolved in ethyl acetate 988 kg. To the solution were added methane sulfonylchloride 130.7 kg at 15-0° C. and triethylamine 115.4 kg, successively, and the solution was stirred at 20-30° C. for 15 min. The reaction solution was washed with aqueous 5% sodium bicarbonate solution to separate an organic phase, which was washed with aqueous 10% sodium chloride solution. The separated organic phase was mixed with n-heptane and cooled gradually down to 5° C. or lower to deposit crystals, which were filtered by a Nutsche funnel to obtain a wet crystal of crude N-tert-butoxycarbonyl-3(S)-amino-2(R)-hydroxy-4-phenyl-1-methanesulfonyloxybutane 793 kg (Net.368.9 kg).

1. customto obtain the crude N-tert-butoxycarbonyl-3(S)-amino-2(R)-hydroxy-4-phenyl-1-butanol, which
2. washThe reaction solution was washed with aqueous 5% sodium bicarbonate solution
3. customto separate an organic phase, which
4. washwas washed with aqueous 10% sodium chloride solution
5. additionThe separated organic phase was mixed with n-heptane
6. filtrationwere filtered by a Nutsche funnel