反应详情

To a solution of trifluoroacetic anhydride (45 mL) in trifluoroacetic acid (45 mL) at 4° C. under N2 was added (2,2-diethoxyethyl)-(3-ethylphenyl)amine (11.47 g, 48.36 mmol). After stirring for 30 min, the cold mixture was diluted with trifluoroacetic acid (60 mL). The mixture was stirred at reflux for 2.5 d, concentrated and extracted with methylene chloride (3×100 mL). The combined organic layers were washed with saturated NaHCO3 (3×60 mL), saturated NaCl (60 mL), dried (MgSO4) and concentrated. Flash chromatography (SiO2, 25% EtOAc/hexanes) gave the title compound (1.6 g, 23%) as a brown crystalline solid. 1H NMR (CDCl3) δ 8.03 (bs, 1H), 7.57 (m, 1H), 7.18 (s, 1H), 7.12 (m, 1H), 6.68 (m, 1H), 6.46 (m, 1H), 2.73 (m, 2H), 1.26 (m, 3H)

1. stirringThe mixture was stirred
2. temperatureat reflux for 2.5 d
3. concentrationconcentrated
4. extractionextracted with methylene chloride (3×100 mL)
5. washThe combined organic layers were washed with saturated NaHCO3 (3×60 mL), saturated NaCl (60 mL)
6. dry with materialdried (MgSO4)
7. concentrationconcentrated