Sodium borohydride → HCID 69024598, compound

Temperature

-20 °C

Calcium chloride (16.63 g, 149.8 mmol) is added to a stirring suspension of sodium borohydride (11.33 g, 299.6 mmol) in ethanol (300 mL) at −40° C. The heterogeneous mixture is warmed to −20° C. and stirred for 1 h. (S)-2-Benzyloxycarbonylamino-3-methoxy-propionic acid methyl ester (20 g, 74.9 mmol) in abs EtOH (250 mL) is then added via cannula transfer. The heterogeneous mixture is stirred at −20° C. for 3 h. The reaction is quenched with water (400 mL) and carefully acidified with 1.0 M HCl. The aqueous layer is extracted with CH2Cl2 (4×200 mL) and the combined organic phases are washed with brine (200 mL), dried over anhydrous Na2SO4 and concentrated to afford a colorless oil. The mixture is absorbed onto the silica gel and chromatographed on silica gel (hexane:EtOAc, 4:1>2:1>1:1>1:2) to afford 11.5 g (64%) of (R)-(1-hydroxymethyl-2-methoxy-ethyl)-carbamic acid benzyl ester as a colorless oil.

1. additionis then added via cannula transfer
2. customThe reaction is quenched with water (400 mL)
3. extractionThe aqueous layer is extracted with CH2Cl2 (4×200 mL)
4. washthe combined organic phases are washed with brine (200 mL)
5. dry with materialdried over anhydrous Na2SO4
6. concentrationconcentrated
7. customto afford a colorless oil
8. customThe mixture is absorbed onto the silica gel
9. customchromatographed on silica gel (hexane:EtOAc, 4:1>2:1>1:1>1:2)

ORD record

ord-bdfad6257b03408999a56243487fd409

Source dataset

uspto-grants-2009_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07612075B2