Sodium borohydride → (2R,3S,5R)-5-[(1S,2S)-2-Amino-3-(2-ethylphenyl)-1-hydroxypropyl]-2-(2,2-dimethylpropoxy)-3-methylmorpholine-4-carboxylic acid tert-butyl ester

Participants

Reaction Steps

Dissolve the mixture of diastereomers from the previous reaction containing (2R,3S,5R)-2-(2,2-dimethylpropoxy)-5-[(1R,2S)-3-(2-ethylphenyl)-1-hydroxy-2-nitropropyl]-3-methylmorpholine-4-carboxylic acid tert-butyl ester in dry methanol (12 mL) and add nickel (II) chloride (267 mg, 2.06 mmol). To the resulting suspension, add sodium borohydride (284 mg, 7.5 mmol) portion-wise over 1 minute. After 30 minutes, quench with water and reduce the volume on the rotary evaporator. Add more water and saturated aqueous sodium chloride. Extract with ethyl acetate. Combine the extracts, dry (sodium sulfate), filter and concentrate to give a diastereomeric mixture of amines containing the desired compound as a light brown oil (418 mg, 85%).

Provenance & Evidence