Triethylamine → 1-{[(R)-5-(4-cyano-benzyl)-7-(3,5-dichloro-phenyl)-5-methyl-6-oxo-6,7-dihydro-5H-imidazo[1,2-a]imidazole-3-carbonyl]-amino}-cyclopropanecarboxylic acid tert-butyl ester

Participants

Reaction Steps

(R)-5-(4-Cyano-benzyl)-7-(3,5-dichloro-phenyl)-5-methyl-6-oxo-6,7-dihydro-5H-imidazo[1,2-a]imidazole-3-carboxylic acid (3.3 g, 7.48 mmol), 1-amino-cyclopropane-carboxylic acid tert-butyl ester (1.8 g, 11.4 mmol) and HATU (4.27 g, 11.2 mmol) were dissolved in anhydrous DMF (20 mL). The mixture was stirred for 15 min. Et3N (2.95 mL, 20.4 mmol) was then added to the reaction. After 30 min, the crude reaction was concentrated in vacuo. The residue was purified by flash chromatography on silica gel (10% to 30% EtOAc/Hexanes) to give 1-{[(R)-5-(4-cyano-benzyl)-7-(3,5-dichloro-phenyl)-5-methyl-6-oxo-6,7-dihydro-5H-imidazo[1,2-a]imidazole-3-carbonyl]-amino}-cyclopropanecarboxylic acid tert-butyl ester (3.8 g, 6.55 mmol, 87.5%) as a white solid, m/z 580.5 [M+1]+.

Provenance & Evidence