反应详情

温度

187.5 °C

A 250 mL, 3 neck, flask fitted with a thermometer, condenser, and stopper is charged 2-(4-hydroxyphenyl)-3-(4-methoxybenzoyl)-6-hydroxybenzo[b]thiophene (3.0 g, 7.97 mmol) and pyridine hydrochloride (18.5 g, 160 mmol). The contents are heated to 185-190° C. and held at this temperature for 90 minutes. The hot mixture is then poured into 250 mL of ice/water. A yellow solid formed with this addition. The material is extracted into 250 mL of ethyl acetate. The aqueous is then back-extracted with 100 mL of ethyl acetate. The combined organics are washed with 150 mL 1N hydrochloric acid and 150 mL brine. The solvent is removed in vacuo giving a viscous oil. To the oil is added 10 mL of 1:1 methylene chloride/hexanes which induced crystallization. The slurry is cooled to 0° C. and stirred at this temperature for 1 hour. The product is collected by vacuum filtration and washed with 25 mL of 4:1 hexanes/methylene chloride. Drying the solid at 100° C. for 5 hours afforded 2.5 g (86.2%) of a dark yellow solid containing approximately 3% monomethoxy starting material. An analytical sample is obtained by chromatography on silica gel (15:1 methylene chloride:methanol). mp 135° C. (dec); 1H NMR (300.1 MHz, DMSO-d6) δ 6.67 (d, 2H), 6.71 (d, 2H), 6.85 (dd, 1H), 7.17 (d, 2H), 7.25 (d, 1H), 7.32 (d, 1H), 7.57 (d, 2H), 9.73 (br s, 2H), 10.41 (br s, 1H); 13C NMR (75.5 MHz, DMSO-d6) d 107.1, 115.1, 115.4, 115.6, 123.4, 123.9, 128.4, 129.7, 129.9, 132.1, 132.4, 139.2, 140.0, 155.4, 157.8, 162.5, 192.4; MS (FD+) m/e 362 (100), 363 (24), 364 (7); HRMS m/e calc'd for C2H15O4S (M+1): 363.069106, found 363.06990.

1. customA 250 mL, 3 neck, flask fitted with a thermometer, condenser, and stopper
2. customA yellow solid formed with this addition
3. extractionThe material is extracted into 250 mL of ethyl acetate
4. extractionThe aqueous is then back-extracted with 100 mL of ethyl acetate
5. washThe combined organics are washed with 150 mL 1N hydrochloric acid and 150 mL brine
6. customThe solvent is removed in vacuo
7. customgiving a viscous oil
8. customcrystallization
9. temperatureThe slurry is cooled to 0° C.
10. filtrationThe product is collected by vacuum filtration
11. washwashed with 25 mL of 4:1 hexanes/methylene chloride
12. customDrying the solid at 100° C. for 5 hours