Sodium borohydride → tert-butyl (1R,3R,4S)-4-((S)-3-benzyloxycarbonylamino-2-oxopyrrolidin-1-yl)-3-(hydroxymethyl)cyclohexylcarbamate

Participants

Reaction Steps

To a solution of (1R,2S,5R)-tert-butyl 2-((S)-3-(benzyloxycarbonylamino)-2-oxopyrrolidin-1-yl)-7-oxo-6-aza-bicyclo[3.2.1]octane-6-carboxylate (4.55 g, 9.94 mmol) in THF (50 mL) and water (50 mL) was added NaBH4, and the mixture was stirred for 5 h at rt. After quenching the reaction with sat. NaHCO3, the product was extracted with EtOAc (2×). The combined extracts were washed with brine, dried (MgSO4), filtered, and concentrated in vacuo to give an oily residue, which crystallized upon tritulation with 4:6 EtOAc and hexane to provide pure ((1R,3R,4S)-4-((S)-3-(benzyloxycarbonyl)amino-2-oxopyrrolidin-1-yl)-3-(hydroxymethyl)cyclohexyl)carbamic acid tert-butyl ester (2.61 g).

Provenance & Evidence