(3S)-4-(benzyloxy)-3-(((tert-butoxy)carbonyl)amino)-4-oxobutanoic acid → Boc-L-Homoser-Obzl

Participants

Reaction Conditions

Reaction Steps

(S)-2-tert-Butoxycarbonylamino-succinic acid 1-benzyl ester (2.62 g, 8.10 mmol) under an atmosphere of nitrogen was dissolved in THF (40 mL) and cooled to 0° C. A 1.0 M borane-THF complex in THF (15 mL) was added dropwise and the reaction mixture was stirred for 3 h, quenched carefully with MeOH (20 mL) and stirred for 20 min. The reaction mixture was treated with MeOH (2×15 mL) and concentrated to dryness. The residue was dissolved in EtOAc and washed with 1N HCl (10 mL), saturated sodium bicarbonate (10 mL), and brine (10 mL). The organic extract was dried over sodium sulfate, filtered and purified on SiO2 to give the intermediate (S)-2-tert-butoxycarbonylamino-4-hydroxy-butyric acid benzyl ester as a clear colorless oil (1.2 g), which was used in the procedure of Preparation 14 to prepare the title compound.

Provenance & Evidence