Hydroquinone → HCID 12546025, compound

Reaction equation

[CH3:1][O:2][C:3](=[C:6]([CH3:8])[CH3:7])[CH2:4][CH3:5].[CH2:9]([O:11]C(C(C)C)=CC)[CH3:10].[CH:18](C=C)=O.C1(C=CC(O)=CC=1)O>>[CH3:1][O:2][C:3]1([CH2:4][CH3:5])[C:6]([CH3:18])([CH3:8])[CH2:7][CH:10]=[CH:9][O:11]1

Participants

Reactant 4

HCID 785Hydroquinone

HCID 7847Acrolein

HCID 519098HCID 519098, compound2×

HCID 12538066HCID 12538066, compound

Product 1

HCID 12546025HCID 12546025, compoundYield 72%

Conditions

Temperature: 165 °C

Procedure

54 g of a mixture of 3-methoxy-4-methyl-3-pentene (I, with R = CH3) and 3-methoxy-4-methyl-2-pentene (II, with R = CH3), which according to the nuclear resonance spectrum comprises about 95% of I and about 5% of II, 32 g of acrolein and 1 g of hydroquinone are heated at 165° C. for 20 hours. Distillation of the reaction mixture gives 58 g of the desired 2-methoxy-2-ethyl-3,3-dimethyl-2,3-dihydro-4H-pyran of boiling point 64° - 67° C./13 mm Hg. This corresponds to a yield of 72% of theory.