Potassium Carbonate → (S)-2-{[(R)-7-(3,5-dichloro-phenyl)-5-(4'-fluoro-biphenyl-4-ylmethyl)-5-methyl-6-oxo-6,7-dihydro-5H-imidazo[1,2-a]imidazole-3-carbonyl]-amino}-propionic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

A solution of (S)-2-{[(R)-5-(4-bromo-benzyl)-7-(3,5-dichloro-phenyl)-5-methyl-6-oxo-6,7-dihydro-5H-imidazo[1,2-a]imidazole-3-carbonyl]-amino}-propionic acid tert-butyl ester (0.20 g, 0.32 mmol), 4-fluorophenyl boronic acid (0.059 g, 0.43 mmol) and K2CO3 (0.15 g, 1.1 mmol) in DME (5 mL) was degassed under N2 for 10 minutes. To this was added PdCl2(dppf) (5 mg) and the mixture heated at 80° C. for 12 h. The resulting black mixture was cooled to room temperature, diluted with saturated NH4Cl and extracted with EtOAc (3×50 mL). The combined organic extracts were washed with water, brine, dried with MgSO4 and concentrated. The residue was purified by silica gel chromatography to afford 150 mg of (S)-2-{[(R)-7-(3,5-dichloro-phenyl)-5-(4′-fluoro-biphenyl-4-ylmethyl)-5-methyl-6-oxo-6,7-dihydro-5H-imidazo[1,2-a]imidazole-3-carbonyl]-amino}-propionic acid tert-butyl ester as a white solid, m/z 637.5 [M+]+.

Provenance & Evidence