Sodium borohydride → Benzyl [(2S)-3-hydroxybutan-2-yl]carbamate

Under argon, 810 mg of benzyl [(2S)-3-oxobutan-2-yl]carbamate (Example 150A, 3.7 mmol, 1 equivalent) were initially charged in 12 ml of dry THF and 12 ml of methanol, and 208 mg of sodium borohydride (5.5 mmol, 1.5 equivalents) were added at 0° C. After 2 h at 0° C., the mixture was concentrated, water and saturated aqueous sodium bicarbonate solution were added to the residue and the mixture was extracted four times with ethyl acetate. The combined organic phases were washed with saturated aqueous sodium chloride solution, dried over magnesium sulphate and concentrated. This gave 777 mg (90% of theory) of the title compound.

1. concentrationthe mixture was concentrated
2. additionwater and saturated aqueous sodium bicarbonate solution were added to the residue
3. extractionthe mixture was extracted four times with ethyl acetate
4. washThe combined organic phases were washed with saturated aqueous sodium chloride solution
5. dry with materialdried over magnesium sulphate
6. concentrationconcentrated

ORD record

ord-7ba43b11749e491d97cb162913082700

Source dataset

uspto-grants-2015_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09126998B2