Water → 2-Cyclopenten-1-one, 4-hydroxy-3-methyl-2-(2-propen-1-yl)-

Reaction equation

O[C:2]1([CH3:11])[CH:6]([CH2:7][CH:8]=[CH2:9])[C:5](=[O:10])[CH:4]=[CH:3]1.[Cl-].[Na+].[OH2:14]>>[CH2:7]([C:6]1[C:5](=[O:10])[CH2:4][CH:3]([OH:14])[C:2]=1[CH3:11])[CH:8]=[CH2:9]

Participants

Reactant 3

HCID 962Water

HCID 5234Sodium Chloride

HCID 128798724-Hydroxy-4-methyl-5-(prop-2-en-1-yl)cyclopent-2-en-1-one

Product 1

HCID 110832-Cyclopenten-1-one, 4-hydroxy-3-methyl-2-(2-propen-1-yl)-

Procedure

In an autoclave, 4-hydroxy-4-methyl-5-allyl-2-cyclopentenone (20 g) and water (400 ml) were charged, and the resultant mixture was stirred at 180° C. for 6 hours in a nitrogen atmosphere. After cooling, sodium chloride (50 g) was added to the reaction mixture, and the resulting mixture was extracted with methyl isobutyl ketone. The extract was concentrated under reduced pressure to give 2-allyl-3-methyl-4-hydroxy-2-cyclopentenone (19 g). Yield, 95%. M.P. 130°-132° C./1.2 mmHg.