Hydrochloric Acid → 2,5-Cyclohexadiene-1-acetic acid, 1-hydroxy-4-oxo-, ethyl ester

HRID 1444975Notes

Reaction equation

HRID 1444975 reaction equation
Br[Zn][CH2:3][C:4]([O:6][CH2:7][CH3:8])=[O:5].[C:9]1(=[O:16])[CH:14]=[CH:13][C:12](=[O:15])[CH:11]=[CH:10]1.Cl.C(OCC)(=O)C>C1COCC1>[OH:16][C:9]1([CH2:3][C:4]([O:6][CH2:7][CH3:8])=[O:5])[CH:14]=[CH:13][C:12](=[O:15])[CH:11]=[CH:10]1

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 4650QuinoneHCID 8857Ethyl AcetateHCID 178472539HCID 178472539, compound

Product 1

HCID 1003232,5-Cyclohexadiene-1-acetic acid, 1-hydroxy-4-oxo-, ethyl esterYield 70%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent3×

Procedure

Under nitrogen atmosphere, 6 mL of THF was added to 1.22 g (2 mmol, 0.6 equivalent) of (BrZnCH2COOEt.THF)2. Under argon atmosphere, a solution of 0.36 g (3.33 mmol) of p-benzoquinone in 2.5 mL of THF was added dropwise while stirring at 0˜5° C. The mixture was stirred at 20˜25° C. for 1 hour. 5 mL of 1N hydrochloric acid was added dropwise at 20° C. or lower, followed by dilution with 25 mL of ethyl acetate. Then, the layers were separated. The organic layer was washed successively with 5 mL (×2) of 1N hydrochloric acid, 5 mL of water, 5 mL (×2) of an aqueous saturated sodium bicarbonate solution, and 5 mL (×2) of an aqueous saturated sodium chloride solution. After washing, the organic layer was dried with anhydrous magnesium sulfate. After concentration under reduced pressure, purification with silica gel column (developing solvent; ethyl acetate/n-hexane=1/3, 1/2) afforded 0.46 g of the desired product (yield 70%).

Workup

  1. stirringThe mixture was stirred at 20˜25° C. for 1 hour
  2. customThen, the layers were separated
  3. washThe organic layer was washed successively with 5 mL (×2) of 1N hydrochloric acid, 5 mL of water, 5 mL (×2) of an aqueous saturated sodium bicarbonate solution, and 5 mL (×2) of an aqueous saturated sodium chloride solution
  4. washAfter washing
  5. dry with materialthe organic layer was dried with anhydrous magnesium sulfate
  6. concentrationAfter concentration
  7. customunder reduced pressure, purification with silica gel column (developing solvent; ethyl acetate/n-hexane=1/3, 1/2)

Sources & evidence

ORD record
ord-8bee16bf3fa54bcba7ad2db511d5a41e
Source dataset
uspto-grants-2010_02
Patent number
US07662974B2

Reaction notes

Loading…