Ethanol → Ethyl 2H-tetrafluorobenzoate

Temperature

0 °C

A solution of 2,3,4,5-tetrafluorobenzoic acid (4.68 g, 24.1 mmol) in dichloromethane (50 mL) at 0° C. is treated with oxalyl chloride (11.5 mL, 132 mmol) followed by N,N-dimethylformamide (4 drops). The mixture is stirred at 0° C. for 5 minutes and then at room temperature for 1.5 hours. The mixture is concentrated to dryness and subsequently co-evaporated from benzene. The resulting acid chloride is diluted with dichloromethane (50 mL), cooled to 0° C., and anhydrous ethanol (15.0 mL, 256 mmol) is added dropwise. The resulting solution is stirred at room temperature for 4.5 hours, then poured into saturated NaHCO3 and extracted with chloroform. The combined organic extracts are washed with brine, dried over Na2SO4, filtered, and concentrated under vacuum to afford the title compound (5.37 g). 1H NMR (CDCl3): δ 7.67–7.55 (m, 1H), 4.42 (q, 2H), 1.41 (t, 3H).

1. waitat room temperature for 1.5 hours
2. concentrationThe mixture is concentrated to dryness
3. additionThe resulting acid chloride is diluted with dichloromethane (50 mL)
4. temperaturecooled to 0° C.
5. stirringThe resulting solution is stirred at room temperature for 4.5 hours
6. extractionextracted with chloroform
7. washThe combined organic extracts are washed with brine
8. dry with materialdried over Na2SO4
9. filtrationfiltered
10. concentrationconcentrated under vacuum

ORD record

ord-e23d6a74247b400bb87430ce70adc43b

Source dataset

uspto-grants-2006_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07094780B1