Benzyl Chloride → 3-Benzyloxy-2-methyl-4-pyrone

HRID 374442Notes

Reaction equation

HRID 374442 reaction equation
[OH-].[Na+].[OH:3][C:4]1[C:9](=[O:10])[CH:8]=[CH:7][O:6][C:5]=1[CH3:11].[CH2:12](Cl)[C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1>CO.O>[CH2:12]([O:3][C:4]1[C:9](=[O:10])[CH:8]=[CH:7][O:6][C:5]=1[CH3:11])[C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1

Participants

6

Reactant 3

HCID 7503Benzyl ChlorideHCID 8369MaltolHCID 14798Sodium Hydroxide

Product 1

HCID 14901193-Benzyloxy-2-methyl-4-pyroneYield 76.8%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 962WaterSolvent

Procedure

A solution of sodium hydroxide (126 g, 1.1 mol) in 1000 ml of methanol in water (9:1 v/v) was added to 3-hydroxy-2-methyl-4-pyrone (126.12 g, 1 mol). Benzyl chloride (126.59 ml, 1.1 mol) was then added slowly and the mixture was refluxed for 10 hours with rapid stirring. The resultant solution was cooled, the methanol removed by rotary evaporation and the aqueous solution was extracted with dichloromethane (3×250 ml). The combined dichloromethane extracts were washed with 5% sodium hydroxide and then with water, dried over anhydrous sodium sulphate, filtered and evaporated to dryness. The resultant solid was recrystallised from diethylether to yield the title compound in 76.8% yield as colourless needles, m.p. 53°-55° C.

Workup

  1. temperaturethe mixture was refluxed for 10 hours with rapid stirring
  2. customthe methanol removed by rotary evaporation
  3. extractionthe aqueous solution was extracted with dichloromethane (3×250 ml)
  4. washThe combined dichloromethane extracts were washed with 5% sodium hydroxide
  5. dry with materialwith water, dried over anhydrous sodium sulphate
  6. filtrationfiltered
  7. customevaporated to dryness
  8. customThe resultant solid was recrystallised from diethylether

Sources & evidence

ORD record
ord-4b3255547edb45e0b464228a6c51cbbc
Source dataset
uspto-grants-1996_01
Patent number
US05480894

Reaction notes

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