Potassium Carbonate → Ethyl 3-chloro-6-benzofurancarboxylate

HRID 2181679Notes

Reaction equation

HRID 2181679 reaction equation
Cl[C@H:2]1[C@H:6]([Cl:7])[C:5]2[CH:8]=[CH:9][C:10]([C:12]([O:14][CH3:15])=[O:13])=[CH:11][C:4]=2[O:3]1.[C:16]([O-])([O-])=O.[K+].[K+]>CCO>[Cl:7][C:6]1[C:5]2[CH:8]=[CH:9][C:10]([C:12]([O:14][CH2:15][CH3:16])=[O:13])=[CH:11][C:4]=2[O:3][CH:2]=1

Participants

4

Reactant 2

HCID 11430Potassium CarbonateHCID 131724883HCID 131724883, compound

Product 1

HCID 22481771Ethyl 3-chloro-6-benzofurancarboxylateYield 58.1%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

trans-Methyl 2,3-dichloro-2,3-dihydro-1-benzofuran-6-carboxylate (58 mg, 0.23 mmol) is dissolved in EtOH (2 ml), treated with K2CO3 (187 mg, 1.35 mmol) and stirred at RT overnight. The mixture is concentrated to dryness, the residue is dissolved in 50% saturated NaCl (10 ml) and extracted with CH2Cl2 (3×10 ml). The combined organics are dried (K2CO3), filtered, and concentrated in vacuo to a yellow oil. The crude material is chromatographed over 10 g slurry-packed silica gel, eluting with 25% EtOAc/hexane. The appropriate fractions are combined and concentrated to afford 30 mg (58%) of ethyl 3-chloro-1-benzofuran-6-carboxylate as a yellow oil. 1H NMR (400 MHz, CDCl3): δ 1.44, 4.43, 7.66, 7.79, 8.07, 8.21 ppm.

Workup

  1. concentrationThe mixture is concentrated to dryness
  2. dissolutionthe residue is dissolved in 50% saturated NaCl (10 ml)
  3. extractionextracted with CH2Cl2 (3×10 ml)
  4. dry with materialThe combined organics are dried (K2CO3)
  5. filtrationfiltered
  6. concentrationconcentrated in vacuo to a yellow oil
  7. customThe crude material is chromatographed over 10 g slurry-packed silica gel
  8. washeluting with 25% EtOAc/hexane
  9. concentrationconcentrated

Sources & evidence

ORD record
ord-74cf26ff999f4e0f88759c5168664518
Source dataset
uspto-grants-2005_05
Patent number
US06894042B2

Reaction notes

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