反应详情

To a solution of 4-(4-Amino-2-fluoro-phenyl)-piperazine-1-carboxylic acid tert-butyl ester (0.50 g, 1.7 mmol) and biphenyl-2-carboxylic acid (0.38 g, 1.9 mmol) in CH2Cl2 (30 mL) was added 1-hydroxybenzotriazole hydrate (0.27 g, 2.0 mmol), and 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride (0.38 g, 2.0 mmol). After stirring at room temperature for 18 h, the reaction was diluted with 1 N NaOH (50 mL) and extracted with CH2Cl2 (3×50 mL). The organic extracts were combined, dried (Na2SO4), and concentrated. Chromatography of the resulting residue (SiO2: EtOAc/hexanes) yielded 4-{4-[(biphenyl-2-carbonyl)-amino]-2-fluoro-phenyl}-piperazine-1-carboxylic acid tert-butyl ester, which was further dissolved in MeOH (20 mL) and 4N HCl in dioxanes. After stirring for 5 h, the reaction mixture was concentrated down, neutralized with 1N NaOH, and extracted with EtOAc (3×75mL). The orgranic extracts were combined, dried (Na2SO4), and the solvent was evaporated under reduced pressure to yield the title compound.

1. extractionextracted with CH2Cl2 (3×50 mL)
2. dry with materialdried (Na2SO4)
3. concentrationconcentrated