反应详情

To a solution of (4-formyl-3,5-dimethylphenylamino)-acetic acid methyl ester (800 mg) and 3,4-diamino-N-(3,4-dimethylphenyl)-benzamide (694 mg) in DMSO (15 mL) was added Yb(OTf)3 (390 mg) and Cu(OTf)2 (228 mg). The solution was stirred at room temperature for 18 h then the reaction mixture was partioned between water and EtOAc The aqueous layer was extracted with EtOAc. The combined organic layers were dried, filtered and concentrated. The residue was purified by flash chromatography (amino-column) using hexanes/ethyl acetate (1:4) to give {4-[5-(3,4-dimethylphenylcarbamoyl)-1H-benzoimidazol-2-yl]-3,5-dimethylphenylamino}-acetic acid methyl ester as a light yellow solid. MS (ESI)m/z 457 (M+H); 1H NMR (MeOD, 400 MHz) δ 8.21 (s, 1H), 7.85 (dd, 1H), 7.67 (s, 1H), 7.47 (d, 1H), 7.42 (dd, 1H), 7.12 (d, 1H), 6.42 (s, 2H), 3.97 (s, 2H), 3.75 (s, 3H), 2.29 (s, 3H), 2.26 (s, 3H), 2.09 (s, 6H).

1. extractionwas extracted with EtOAc
2. customThe combined organic layers were dried
3. filtrationfiltered
4. concentrationconcentrated
5. customThe residue was purified by flash chromatography (amino-column)