Hydroquinone → 2-Ethoxy-4-phenyl-3,4-dihydro-2h-pyran

Reaction equation

[CH:1]1[CH:6]=[CH:5][C:4](/[CH:7]=[CH:8]/[CH:9]=[O:10])=[CH:3][CH:2]=1.[CH:11]([O:13][CH2:14][CH3:15])=[CH2:12].C1(C=CC(O)=CC=1)O>>[CH2:11]([O:13][CH:14]1[CH2:15][CH:7]([C:4]2[CH:5]=[CH:6][CH:1]=[CH:2][CH:3]=2)[CH:8]=[CH:9][O:10]1)[CH3:12]

Participants

Reactant 3

HCID 785Hydroquinone

HCID 8023Ethyl vinyl ether

HCID 637511Cinnamaldehyde

Product 1

HCID 2801772-Ethoxy-4-phenyl-3,4-dihydro-2h-pyranYield 87.2%

Procedure

313 g (2.37 Mole) of cinnamic aldehyde, 290 g (4.03 Mole) of ethyl vinyl ether and 45 g of hydroquinone were heated at 200° for 16 hours in a 1 l stainless steel autoclave (pressure about 20 atm.). After fractional distillation of the crude material thus obtained, there were isolated 422 g (87% yield) of 2-ethoxy-4-phenyl-3,4-dihydro-2H-pyran, b.p. 89°/0.02 Torr;