反应详情

温度

-10 °C

A solution of N-Boc cyanoalanine (2 g, 9.3 mmol) in THF (30 mL) was cooled in an ice/NaCl bath to −10° C. and treated with triethylamine (0.94 g, 9.3 mmol) followed by dropwise addition of isobutyl chloroformate (1.35 g, 9.9 mmol). The reaction mixture was stirred for 4 minutes at −10° C. and filtered through a coarse scintered glass funnel. Meanwhile, in another flask, a solution of NaBH4 (0.71 g, 19 mmol) in water (10 mL) was prepared and cooled in an ice/water bath. The filtered solution of the mixed anhydride was added dropwise to the cold NaBH4 solution and the resulting mixture was stirred for 2 hours. The THF was removed on the rotary evaporator and the reaction was acidified with 5% NaHSO4 solution to pH 3 and diluted with ethyl acetate and water. The organics were extracted twice with aqueous NaHCO3 and dried over MgSO4. The solvent was removed to afford 1.2 g (64%) of (S)-(2-Cyano-1-hydroxymethyl-ethyl)-carbamic acid tert-butyl ester; 1H NMR (CDCl3, 400 MHz) δ 1.45 (s, 9H), 2.09-2.17 (m, 1H), 2.73 (d, 1H, J=6.0), 3.76 (dd, 1H, J1=4.7, J2=10.8), 3.80-3.86 (m, 1H), 3.91-3.99 (m, 1H), 4.98-5.07 (m, 1H).

1. filtrationfiltered through a coarse scintered glass funnel
2. temperaturecooled in an ice/water bath
3. stirringthe resulting mixture was stirred for 2 hours
4. customThe THF was removed on the rotary evaporator
5. additiondiluted with ethyl acetate and water
6. extractionThe organics were extracted twice with aqueous NaHCO3
7. dry with materialdried over MgSO4
8. customThe solvent was removed