ethyl 2-(4,6,7-trifluoro-1H-benzoimidazol-2-yl)propionate → ethyl 2-(2-{2-[1-(4,6,7-trifluoro-1H-benzoimidazol-2-yl)ethyl]-3-methyl-3H-benzoimidazol-5-carbonylamino}ethoxy}benzoate

Participants

Reaction Conditions

Reaction Steps

Ethyl 2-(4,6,7-trifluoro-1H-benzoimidazol-2-yl)propionate (988 mg, 3.63 mmol) and ethyl 2-[2-(4-amino-3-methylaminobenzoylamino)ethoxy]benzoate (1.3 g, 3.63 mmol) were combined and placed under vacuum for 4 hours and then further combined with DMPU (4 ml). The mixture was stirred until in solution, evacuated overnight under high vacuum to remove residual gases, heated to 195° C. under a nitrogen stream for 4 hours, cooled to room temperature and partitioned between ethyl acetate and water. The organic layer was separated and washed with brine, dried over sodium sulfate and concentrated. The residue was purified by chromatography on silica (stepwise gradient of 100% hexane to 100% ethyl acetate) and further purified by crystallization from MeOH/THF/water to provide ethyl 2-(2-{2-[1-(4,6,7-trifluoro-1H-benzoimidazol-2-yl)ethyl]-3-methyl-3H-benzoimidazol-5-carbonylamino}ethoxy}benzoate (1.0 g, 49%) as a white crystalline solid:

Provenance & Evidence