反应详情

温度

-78 °C

(The following reaction is done in an anhydrous N2 atmosphere.) Dissolve cis-{4-[3-(3,4,5-Trimethoxy-phenyl)-propionylamino]-cyclohexanecarboxylic acid methyl ester (75) (82 mg, 0.21 mmol) in anhydrous DCM (2.0 mL), cool the solution to −78° C. and add dropwise BBr3 (205 μL, 2.17 mmol). Stir the reaction mixture for 20 min at −78° C. and after slowly warming up for additional 2 h at rt Add dropwise water, followed by DCM and MeOH and remove solvent. Purify the crude product by preparative RP HPLC (gradient, water/CH3CN 95:5 to 5:95) to obtain cis-4-[3-(3,4,5-Trihydroxy-phenyl)-propionylamino]-cyclohexanecarboxylic acid (76) (7 mg, 10%) as a colorless sticky solid. 1H NMR (400 MHz, CD3OD): 1.47-1.60 (m, 2H); 1.62-1.73 (m, 4H); 1.91-2.02 (m, 2H); 2.42 (t, 2H, J=7.6 Hz); 2.47-2.54 (m, 1H); 2.71 (t, 2H, J=7.3 Hz); 3.75-3.84 (m, 1H); 6.23 (s, 2H).

1. custom(The following reaction
2. temperatureafter slowly warming up for additional 2 h at rt
3. customremove solvent
4. customPurify the crude product by preparative RP HPLC (gradient, water/CH3CN 95:5 to 5:95)