反应详情

温度

-40 °C

4-[2,4-Bis(tert-butyldimethylsilyloxy)phenyl]cyclohexanone oxime (120 mg) was dissolved in anhydrous methanol (10 ml) with stirring. The solution was cooled to −40° C., and nickel chloride hexahydrate (133 mg) was added. Stirring was continued for 10 min before sodium borohydride (42 mg) was added in one portion. The reaction mixture was stirred at −40° C. for 20 min and water (0.5 ml) was added. The reaction mixture was allowed to warm to room temperature with stirring. Silica gel was added and the solvent removed in vacuo. Purification via flash column chromatography (SiO2 eluting with CH2Cl2:MeOH:NH4OH, 44:50:6 v/v) afforded the desired product as a pale brown oil (83 mg, 71%) and a mixture of diastereoisomers. δH (CD3OD): 0.22 (6H, s), 0.27 (6H, s), 1.02 (9H, s), 1.08 (9H, s), 1.24-1.40 (1H, m), 1.42-1.57 (1H, m), 1.57-1.68 (1H, m), 1.71-1.90 (4H, m), 1.99-2.07 (1H, m), 2.84-2.98 (1H, m), 4.28-4.40 (1H, m), 6.34 (1H, d), 6.44 (1H, t), 7.04 (0.5H, d), 7.16 (0.5H, d); m/z (ES+) 436 (M+1)+.

1. stirringStirring
2. additionwas added in one portion
3. stirringThe reaction mixture was stirred at −40° C. for 20 min
4. temperatureto warm to room temperature
5. stirringwith stirring
6. additionSilica gel was added
7. customthe solvent removed in vacuo
8. customPurification via flash column chromatography (SiO2 eluting with CH2Cl2:MeOH:NH4OH, 44:50:6 v/v)