Propanedioyl dichloride → 5-Ethyl-4-hydroxy-6-methyl-2-pyrone

HRID 323926

Reaction equation

HRID 323926 reaction equation
C[Si](C)(C)[O:3][C:4](=[CH:6][CH2:7][CH3:8])[CH3:5].[C:11](Cl)(=[O:16])[CH2:12][C:13](Cl)=[O:14]>CCOCC>[CH2:7]([C:6]1[C:11]([OH:16])=[CH:12][C:13](=[O:14])[O:3][C:4]=1[CH3:5])[CH3:8]

Participants

4

Reactant 2

HCID 74269Propanedioyl dichloride2×HCID 545738712-Trimethylsilyloxy-2-pentene

Product 1

HCID 547031925-Ethyl-4-hydroxy-6-methyl-2-pyroneYield 42.3%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Conditions

Temperature
-78 °C

Procedure

In 200 mL of ether, was dissolved 13.6 g (85.9 mmol) of 2-trimethylsilyloxy-2-pentene, and 4.6 mL (47.3 mmol) of malonyl chloride was added dropwise to the solution while stirring the solution at −78° C. After the addition of malonyl chloride, the solution was stirred for 1 hour at −78° C., and then, stirred over night while gradually heating the solution to room temperature. The precipitate was filtered and washed with ether. As a result, 3.08 g (20.0 mmol, 42.3%) of 5-ethyl-4-hydroxy-6-methyl-2-pyrone was obtained.

Workup

  1. additionwas added dropwise to the solution
  2. stirringthe solution was stirred for 1 hour at −78° C.
  3. stirringstirred over night
  4. temperaturewhile gradually heating the solution to room temperature
  5. filtrationThe precipitate was filtered
  6. washwashed with ether

Sources & evidence

ORD record
ord-68ab7f1ed1cc4277a79de6e3ac3ee3b7
Source dataset
uspto-grants-2001_04
Patent number
US06215016B1

Linked notes

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