3,5-Difluoro-4-methoxybenzoic acid → (2R,4S)-5-biphenyl-4-yl-4-(3,5-difluoro-4-methoxy-benzoylamino)-2-methyl-pentanoic acid ethyl ester

Participants

Reaction Steps

To a solution of (2R,4S)-4-amino-5-biphenyl-4-yl-2-methyl-pentanoic acid ethyl ester hydrochloride salt (200 mg, 0.58 mmol) in CH2Cl2 (2 mL) and DMF (2 mL) at rt is added 3,5-difluoro-4-methoxy benzoic acid (108 mg, 0.58 mmol) followed by an addition of TEA (0.32 mL, 2.3 mmol) and HATU (262 mg, 0.69 mmol). The mixture is stirred at r.t. for 4 hours and quenched with saturated NaHCO3 and diluted in ethyl acetate. The organic layer is washed with water, brine, dried over MgSO4, filtered, and concentrated under reduced pressure. The obtained material is purified by preparative silica gel thin-layer chromatography plates (eluent: EtOAc/hepane=3/2) to give 265 mg of (2R,4S)-5-biphenyl-4-yl-4-(3,5-difluoro-4-methoxy-benzoylamino)-2-methyl-pentanoic acid ethyl ester.

Provenance & Evidence