Diisopropylethylamine → Phenylmethyl (3S)-3-{[(5-fluoro-2-pyridinyl)amino]carbonyl}-2-[(2R)-2-({formyl[(phenylmethyl)oxy]amino}methyl)hexanoyl]-1-pyrazolidinecarboxylate

Participants

Reaction Steps

To a solution of (3S)-2-[(2R)-2-({formyl[(phenylmethyl)oxy]amino}methyl)hexanoyl]-1-{[(phenylmethyl)oxy]carbonyl}-3-pyrazolidinecarboxylic acid (1 g, 1.95 mmol) in THF (15 mL) under N2 was added 2,4,6-trichlorobenzoyl chloride (0.572 g, 2.34 mmol) and DIPEA (1.68 mL, 9.75 mmol). The mixture was stirred at rt for 2 h. THF was removed under vacuum and toluene (15 mL) was added. To this mixture was added 5-fluoro-2-pyridinamine (0.262 g, 2.34 mmol) and DMAP (47.5 mg, 0.39 mmol). After being stirred at rt overnight, the mixture was diluted with EtOAc (50 mL) and washed with citric acid and brine. The organic solution was dried and concentrated. The residue was purified by flash column chromatography eluting with EA/PE (1:5) to provide the title compound (0.23 g, 19%) as colorless oil.

Provenance & Evidence