Potassium tert-butoxide → 2,2-dimethyl-2H-pyran-3,5(4H,6H)-dione

HRID 1862444Notes

Reaction equation

HRID 1862444 reaction equation
CC(C)([O-])C.[K+].[CH3:7][C:8]([CH3:18])([O:12][CH2:13][C:14](OC)=[O:15])[C:9](=[O:11])[CH3:10]>CCOCC>[CH3:7][C:8]1([CH3:18])[C:9](=[O:11])[CH2:10][C:14](=[O:15])[CH2:13][O:12]1

Participants

4

Reactant 2

HCID 23665647Potassium tert-butoxideHCID 85791200Methyl (1,1-dimethyl-2-oxopropoxy)acetate

Product 1

HCID 140728872,2-dimethyl-2H-pyran-3,5(4H,6H)-dione

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent2×

Procedure

Potassium tert-butoxide (1M in tert-butanol, 12.1 mL, 12.1 mmol) in ether (7.5 mL) at 0° C. under N2 gas was treated with the product from Example 43B in ether (3 mL). After 10 minutes, the reaction mixture was quenched into 2N HCl (25 mL) and extracted with ether (3×25 mL). The organic layers were combined, washed with brine, dried over Na2SO4, concentrated to an oil, treated with 10% dichloromethane in hexane (5 mL), and placed in the freezer for 1 hour. The resulting crystals were collected by filtration, washed with a cold solution of 10% dichloromethane in hexane, and dried to provide the title compound (431 mg). 1H NMR (CDCl3) δ 1.25 (s, 6H), 4.16 (s, 2H), 5.20 (s, 1H), 11.70 (s, 1H).

Workup

  1. customthe reaction mixture was quenched into 2N HCl (25 mL)
  2. extractionextracted with ether (3×25 mL)
  3. washwashed with brine
  4. dry with materialdried over Na2SO4
  5. concentrationconcentrated to an oil
  6. additiontreated with 10% dichloromethane in hexane (5 mL)
  7. waitplaced in the freezer for 1 hour
  8. filtrationThe resulting crystals were collected by filtration
  9. washwashed with a cold solution of 10% dichloromethane in hexane
  10. customdried

Sources & evidence

ORD record
ord-71ef6287c3d84c2e9fd73d8b1f25e29c
Source dataset
uspto-grants-2003_03
Patent number
US06538004B2

Reaction notes

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