Ethanol → 2,3,4,6-Tetrafluorobenzoic acid ethyl ester

HRID 10269Notes

Reaction equation

HRID 10269 reaction equation
[F:1][C:2]1[C:10]([F:11])=[C:9]([F:12])[CH:8]=[C:7]([F:13])[C:3]=1[C:4]([OH:6])=[O:5].[C:14](Cl)(=O)[C:15](Cl)=O.C(O)C.C([O-])(O)=O.[Na+]>ClCCl.CN(C)C=O.C1C=CC=CC=1>[CH2:14]([O:5][C:4](=[O:6])[C:3]1[C:7]([F:13])=[CH:8][C:9]([F:12])=[C:10]([F:11])[C:2]=1[F:1])[CH3:15]

Participants

8

Reactant 4

HCID 702EthanolHCID 65578Oxalyl chlorideHCID 516892Sodium BicarbonateHCID 27765912,3,4,6-tetrafluorobenzoic Acid

Product 1

HCID 210411752,3,4,6-Tetrafluorobenzoic acid ethyl esterYield 60.1%

Reagents, catalysts & solvents 3

HCID 6228DimethylformamideCatalystHCID 241BenzeneSolventHCID 6344DichloromethaneSolvent2×

Procedure

2,3,4,6-Tetrafluorobenzoic acid (4.8 g, 24.7 mmol) in dichloromethane (80 mL) is cooled to 0° C. under a nitrogen atmosphere and treated with oxalyl chloride (11.2 mL, 128 mmol) followed by anhydrous N,N-dimethylformamide (2 drops). The mixture is warmed to room temperature and stirred for 2 hours. The solution is co-evaporated with benzene to yield an oil that is taken up in dichloromethane (80 mL), cooled to 0° C. under an inert atmosphere, and treated with anhydrous ethanol (15 mL, 258 mmol). After 5 hours at room temperature, the solution is poured into saturated NaHCO3 and extracted with chloroform. The organic phase is washed with brine, dried over Na2SO4, filtered, and concentrated under vacuum to provide the title compound (3.3 g). This material is used without further purification. 1H NMR (CDCl3): δ 6.93–6.75 (m, 1H), 4.42 (q, 2H), 1.39 (t, 3H).

Workup

  1. customto yield an oil that
  2. temperaturecooled to 0° C. under an inert atmosphere
  3. waitAfter 5 hours at room temperature
  4. extractionextracted with chloroform
  5. washThe organic phase is washed with brine
  6. dry with materialdried over Na2SO4
  7. filtrationfiltered
  8. concentrationconcentrated under vacuum

Sources & evidence

ORD record
ord-58a59fa4c9c44e9090ed4436fa020b49
Source dataset
uspto-grants-2006_08
Patent number
US07094780B1

Reaction notes

Loading…