Ammonium Chloride → Tert-butyl 1-(3-{[(4-chlorophenyl)(2,2-difluorocyclopentyl)acetyl]amino}-4-fluorobenzyl)cyclopropanecarboxylate

Participants

Reaction Steps

490 mg (1.78 mmol) of (4-chlorophenyl)(2,2-difluorocyclopentyl)acetic acid (as diastereomer mixture) were added to a mixture of 4.0 ml of DMF and 1.0 ml of pyridine. At RT, 568.0 mg (2.14 mmol) of tert-butyl 1-(3-amino-4-fluorobenzyl)cyclopropanecarboxylate and 881.7 mg (2.34 mmol) of HATU were added to the resulting solution and the mixture was stirred at RT overnight. The reaction mixture was then added to saturated aqueous ammonium chloride solution and extracted three times with ethyl acetate. The combined organic phases were dried over magnesium sulphate and concentrated under reduced pressure. The crude product was purified by chromatography on silica gel (mobile phase cyclohexane/ethyl acetate 20:1). Further purification of the product obtained in this manner was carried out by preparative RP-HPLC (mobile phase acetonitrile/water). This gave 774.0 mg (83.1% of theory) of the target compound.

Provenance & Evidence