Phosphorus oxychloride → tert-butyl(2S,3S)-8-cyano-2-methyl-1-(2-(methylsulfonyl)acetyl)-4-oxo-2,3,4,5-tetrahydro-1H-benzo[b][1,4]diazepin-3-ylcarbamate

Participants

Reaction Conditions

Reaction Steps

To a 0° C. solution of tert-butyl(3S,4S)-7-cyano-4-methyl-2-oxo-2,3,4,5-tetrahydro-1H-benzo[b][1,4]diazepin-3-ylcarbamate (106 mg, 335 μmol) in pyridine (3.35 ml) was added 2-(methylsulfonyl)acetic acid (50.9 mg, 369 μmol) followed by phosphoryl chloride (61.3 μl, 670 μmol), dropwise. The reaction was stirred at 0° C. for 30 min, then quenched by the addition of H2O and extracted with EtOAc. The combined organic layers were washed with 1 N aq. citric acid, H2O, sat. aq. NaHCO3, and sat. aq. NaCl, dried over Na2SO4, filtered, and concentrated. The crude material was purified by flash chromatography to provide tert-butyl(2S,3S)-8-cyano-2-methyl-1-(2-(methylsulfonyl)acetyl)-4-oxo-2,3,4,5-tetrahydro-1H-benzo[b][1,4]diazepin-3-ylcarbamate (137 mg, 94%) as a white solid. MS m/z 459 (MNa)+.

Provenance & Evidence