反应详情

温度

25 °C

Alternatively, a solution of 4.28 g (15 mmol) of 2-(3,4-dichloro-phenoxy)-5-fluorobenzaldehyde (Preparation no. 5) in 25 mL of acetone was cooled to 5–10° C. and treated via syringe with 5.8 mL (15.6 mmol) of 2.67 M Jones reagent*. After 1 hr at this temperature, the reaction was quenched with 8 mL of isopropanol, allowed to warm to 25° C., and filtered through a pad of d.e. The filtrate was concentrated in vacuo to approximately ¼ volume, diluted with water and extracted several times with CHCl3. The organic layers were washed with water, then with saturated NaCl and finally dried over MgSO4 and concentrated to provide 2-(3,4-dichlorophenoxy)-5-fluoro-benzoic acid as a tan solid, 4.19 g. 1H-nmr (CDCl3, 400 MHz, δ): 7.78 (dd, 1H), 7.38 (d, 1H), 7.27 (m, 1H), 6.98 (m, 2H), 6.81 (dd, 1H). *Jones reagent was prepared from 13.4 g of chromium trioxide and 11.5 mL of concentrated H2SO4, diluted to a final volume of 50 mL with H2O.

1. customthe reaction was quenched with 8 mL of isopropanol
2. filtrationfiltered through a pad of d.e
3. concentrationThe filtrate was concentrated in vacuo to approximately ¼ volume
4. additiondiluted with water
5. extractionextracted several times with CHCl3
6. washThe organic layers were washed with water
7. dry with materialwith saturated NaCl and finally dried over MgSO4
8. concentrationconcentrated