Methyl chloroacetate → 7-Bromobenzofuran-2-carboxylic acid

HRID 2179586Notes

Reaction equation

HRID 2179586 reaction equation
[Br:1][C:2]1[C:3]([OH:10])=[C:4]([CH:7]=[CH:8][CH:9]=1)[CH:5]=O.Cl[CH2:12][C:13]([O:15]C)=[O:14].C(=O)([O-])[O-].[K+].[K+].[OH-].[K+]>[I-].C([N+](CCCC)(CCCC)CCCC)CCC.C1COCC1.O>[Br:1][C:2]1[C:3]2[O:10][C:12]([C:13]([OH:15])=[O:14])=[CH:5][C:4]=2[CH:7]=[CH:8][CH:9]=1

Participants

8

Reactant 4

HCID 7295Methyl chloroacetateHCID 11430Potassium CarbonateHCID 14797Potassium HydroxideHCID 109105553-Bromo-2-hydroxybenzaldehyde

Product 1

HCID 179826517-Bromobenzofuran-2-carboxylic acid

Reagents, catalysts & solvents 3

HCID 67553Tetrabutylammonium IodideCatalystHCID 962WaterSolventHCID 8028TetrahydrofuranSolvent

Procedure

13.5 g (40.3 mmol) of 3-bromo-2-hydroxybenzaldehyde (Example 28A, 62% pure) are heated together with 9.18 g (84.62 mmol) of methyl chloroacetate, 1.49 g (4.03 mmol) of tetra-n-butylammonium iodide and 22.28 g (161.18 mmol) of potassium carbonate at 130° C. for 6 h. After cooling to RT, 100 ml of water and 100 ml of THF, and 13.57 g (241.77 mmol) of potassium hydroxide are added, and the mixture is stirred at RT overnight. The solvent is removed under reduced pressure, and the residue is taken up in 400 ml of water and washed four times with a total of 400 ml of diethyl ether. While cooling in ice, the pH is adjusted to 0 with concentrated hydrochloric acid and five extractions with a total of 700 ml of ethyl acetate are carried out. The organic phase is washed with 100 ml of saturated sodium chloride solution and then dried over magnesium sulphate. The crude product is completely freed of residual solvents under high vacuum and is stirred with 80 ml of diethyl ether. The product is filtered off and washed with a little ice-cold diethyl ether. 4.8 g (47% of theory) of the title compound are isolated.

Workup

  1. customThe solvent is removed under reduced pressure
  2. washwashed four times with a total of 400 ml of diethyl ether
  3. temperatureWhile cooling in ice
  4. extractionthe pH is adjusted to 0 with concentrated hydrochloric acid and five extractions with a total of 700 ml of ethyl acetate
  5. washThe organic phase is washed with 100 ml of saturated sodium chloride solution
  6. dry with materialdried over magnesium sulphate
  7. stirringis stirred with 80 ml of diethyl ether
  8. filtrationThe product is filtered off
  9. washwashed with a little ice-cold diethyl ether

Sources & evidence

ORD record
ord-b6a0505b55254ec89b5d6aa29a649bab
Source dataset
uspto-grants-2015_06
Patent number
US09067931B2

Reaction notes

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