Water → 4-Dodecanoyloxy-6-methyl-5,6-dihydro-2-pyrone

HRID 1165752Notes

Reaction equation

HRID 1165752 reaction equation
[OH:1][C:2]1[CH2:7][CH:6]([CH3:8])[O:5][C:4](=[O:9])[CH:3]=1.N12CCCN[CH:16]1[CH2:15][CH2:14][CH2:13][CH:12]=[CH:11]2.[C:21](Cl)(=[O:31])[CH2:22][CH2:23][CH2:24][CH2:25][CH2:26]CCCC.O>C1(C)C=CC=CC=1>[C:21]([O:1][C:2]1[CH2:7][CH:6]([CH3:8])[O:5][C:4](=[O:9])[CH:3]=1)(=[O:31])[CH2:22][CH2:23][CH2:24][CH2:25][CH2:26][CH2:11][CH2:12][CH2:13][CH2:14][CH2:15][CH3:16]

Participants

6

Reactant 4

HCID 962WaterHCID 66982Decanoyl chlorideHCID 98128211,8-Diazabicyclo[5.4.0]undec-2-ene2×HCID 546805364-hydroxy-6-methyl-5,6-dihydro-2H-pyran-2-one

Product 1

HCID 198609114-Dodecanoyloxy-6-methyl-5,6-dihydro-2-pyrone

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

To a solution of 5.13 g (0.040 mole) of 4-hydroxy-5,6-dihydro-6-methyl-2-pyrone and 6.70 g (0.044 mole) of 1,8-diazabicyclo(5,4,0)-undecene (hereinafter referred to as DBU) in 100 ml of toluene was added dropwise 8.39 g (0.044 mole) of decanoyl chloride with stirring and cooling the reaction mixture in an ice-water bath. After termination of the dropwise addition, the mixture was stirred at room temperature for 7 hours. Water was added to the reaction mixture and the mixture was extracted with toluene. The extract was washed with 5% HCl and then with a saturated aqueous solution of sodium chloride, and dried over anhydrous magnesium sulfate. The solvent in the extract was evaporated under a reduced pressure, and the residue was subjected to silica gel column chromatography to purify the product, 4-dodecanoyloxy-6-methyl-5,6-dehydro-2-pyrone. To a solution of 4-dodecanoyloxy-6-methyl-5,6-dihydro-2-pyrone, thus obtained, in 20 ml of toluene was added 0.06 g of 4-pyrolidinopyridine. The mixture was refluxed for 3 hours and the solvent was removed by evaporation under a reduced pressure. The residue was purified by silica gel column chromatography to obtain 1.6 g (yield: 14%) of 3-decanoyl-6-methyltetrahydropyran-2,4-dione, m.p. 62°-63° C.

Workup

  1. temperaturecooling the reaction mixture in an ice-water bath
  2. additionAfter termination of the dropwise addition
  3. stirringthe mixture was stirred at room temperature for 7 hours
  4. extractionthe mixture was extracted with toluene
  5. washThe extract was washed with 5% HCl
  6. dry with materialwith a saturated aqueous solution of sodium chloride, and dried over anhydrous magnesium sulfate
  7. customThe solvent in the extract was evaporated under a reduced pressure
  8. customto purify the product, 4-dodecanoyloxy-6-methyl-5,6-dehydro-2-pyrone

Sources & evidence

ORD record
ord-ead71b8c3cea450ab9ee18fce72b0dcb
Source dataset
uspto-grants-1990_03
Patent number
US04912100

Reaction notes

Loading…