反应详情

3-Bromo-5-chloro-2-pyridinamine (520 mg, 2.5 mmol), phenol (2.0 g, 21.3 mmol), potassium hydroxide (flakes, 85%, 600 mg, 9.1 mmol) and anhydrous copper (II) sulphate (100 mg, 0.6 mmol) and dimethoxyethane (250 μl) were heated together at 140° C. for 2 h, allowed to cool and the mixture poured into water (50 ml). EtOAc extracts (5×15 ml) were filtered through celite and extracted into 2N HCl (4×10 ml). The combined aqueous extracts were basified with NaOH and re-extracted into EtOAc (3×20 ml), dried over MgSO4, and concentrated to a brown oil (230 mg). Purification by column chromatography on silica gel eluting with hexane—EtOAc (80:20) gave the title compound as a white solid (136 mg, 0.6 mmol). An analytical sample was prepared by crystallisation from hexane:

1. temperatureto cool
2. filtrationEtOAc extracts (5×15 ml) were filtered through celite
3. extractionextracted into 2N HCl (4×10 ml)
4. extractionre-extracted into EtOAc (3×20 ml)
5. dry with materialdried over MgSO4
6. concentrationconcentrated to a brown oil (230 mg)
7. customPurification by column chromatography on silica gel eluting with hexane—EtOAc (80:20)