反应详情

It was prepared using protocols by D. Planchenault et al. Tetrahedron 1995, 51, 5823-5830; D. Nobel, J. Chem. Soc., Chem. Commun. 1993, 419-420 and M. Numazawa et al. J. Chem. Soc., Chem. Commun. 1983, 533-534. A solution of CH3ONa (30% by weight) in CH3OH (17 ml, 89.30 mmol) is added to a solution of 7-bromo-8-hydroxyquinoline (2.00 g; 8.93 mmol), in 125 ml of DMF. The mixture is stirred for 10 minutes under argon. CuCl2.2H2O (0.46 g; 2.68 mmol) is added and the reaction mixture is heated under reflux for 20 hours. After cooling to ambient temperature, water (100 ml) and disodium EDTA dihydrate (7.83 g; 26.80 mmol) are added and the mixture is stirred for 1 hour. The solution is acidified to pH=4-5 with CH3COOH (3 ml) and it is subsequently basified gently with a saturated aqueous solution of NaHCO3. The aqueous phase is extracted with CH2Cl2 (3×100 ml). The combined organic phases are dried over anhydrous Na2SO4 and concentrated under reduced pressure. The solid obtained is purified by silica gel chromatography, eluted using a gradient of CH2Cl2/CH3OH/CH3COOH (94/4/2, v/v) to CH2Cl2/CH3OH (90/10, v/v). The fractions containing the product are combined and washed with a saturated aqueous solution of NaHCO3 (3×100 ml). The organic phase is dried over anhydrous Na2SO4 and concentrated under reduced pressure to yield 7-methyloxy-8-hydroxyquinoline in the form of a white powder (0.65 g; 3.68 mmol, yield=40%). NMR-1H (250 MHz, CDCl3) δ, ppm: 8.77 (dd, 3J (H, H)=4.0 Hz, 4J (H, H)=1.5 Hz, 1H); 8.11 (dd, 3J (H, H)=8.5 Hz, 4J (H, H)=1.5 Hz, 1H); 7.36 (m, 2H), 7.31 (dd, 3J (H, H)=8.5 Hz, 3J (H, H)=4.0 Hz, 1H), 4.06 (s, 3H). NMR-13C (63 MHz, CDCl3) δ, ppm: 148.6 (CH); 144.0 (Cq); 139.7 (Cq); 138.6 (CH); 136.0 (Cq); 123.5 (CH); 119.7 (CH); 117.7 (CH); 116.4 (CH); 57.3 (CH3). MS (CID, NH3): m/z=176 (MH+). Analysis (%) for C10H9NO2.0.1H2O: calculated C, 67.86; H, 5.24; N, 7.91. found C, 67.82; H, 5.11; N, 7.95.

1. customIt was prepared
2. temperaturethe reaction mixture is heated
3. temperatureunder reflux for 20 hours
4. stirringthe mixture is stirred for 1 hour
5. extractionThe aqueous phase is extracted with CH2Cl2 (3×100 ml)
6. dry with materialThe combined organic phases are dried over anhydrous Na2SO4
7. concentrationconcentrated under reduced pressure
8. customThe solid obtained
9. customis purified by silica gel chromatography
10. washeluted
11. additionThe fractions containing the product
12. washwashed with a saturated aqueous solution of NaHCO3 (3×100 ml)
13. dry with materialThe organic phase is dried over anhydrous Na2SO4
14. concentrationconcentrated under reduced pressure