HCID 13011787, compound → 6-Ethoxy-2-methyl-2H-pyran-3(6H)-one

Reaction equation

[CH3:1][CH:2]1[C:7](=[O:8])[CH:6]=[CH:5][CH:4]([OH:9])[O:3]1.C([O-])([O-])O[CH2:12][CH3:13]>C1C=CC=CC=1.[Cl-].[Zn+2].[Cl-]>[CH3:1][CH:2]1[C:7](=[O:8])[CH:6]=[CH:5][CH:4]([O:9][CH2:12][CH3:13])[O:3]1

Participants

Procedure

A 12.8 g quantity of 2-methyl-6-hydroxy-3-oxo-3,6-dihydro-2H-pyran and 14.8 g of ethyl orthoformate are reacted in the presence of 1 g of zinc chloride in 100 ml of benzene with refluxing for 120 minutes. After the reaction, the benzene is distilled off, the residue is poured into 50 ml of water and the mixture is extracted three times with 50 ml portions of ether. The ethereal layer is washed with an aqueous solution of sodium carbonate and then dried over magnesium sulfate. After removing the magnesium sulfate, the dried mass is distilled to remove the ether, and the residue is distilled at a reduced pressure of 30 mm Hg to give 12 g of 2-methyl-6-ethoxy-3-oxo-3,6-dihydro-2H-pyran as a yellow liquid fraction at 82° to 85° C in a yield of 85%.