2-Cyclopentyl-1-(2,3-dichloro-4-methoxyphenyl)prop-2-en-1-one → 6,7-dichloro-2-cyclopentyl-5-methoxy-2,3-dihydro-1H-inden-1-one
Reaction equation
[CH:1]1([C:6](=[CH2:19])[C:7]([C:9]2[CH:14]=[CH:13][C:12]([O:15][CH3:16])=[C:11]([Cl:17])[C:10]=2[Cl:18])=[O:8])[CH2:5][CH2:4][CH2:3][CH2:2]1>S(=O)(=O)(O)O>[Cl:17][C:11]1[C:10]([Cl:18])=[C:9]2[C:14]([CH2:19][CH:6]([CH:1]3[CH2:5][CH2:4][CH2:3][CH2:2]3)[C:7]2=[O:8])=[CH:13][C:12]=1[O:15][CH3:16]Participants
3
Reactant 1
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 20 °C
Procedure
4-(2-Cyclopentyl-2-methyleneacetyl)-2,3-dichloroanisole (33.3 g.) is dissolved in 98% sulfuric acid (150 ml.) and stirred at 20° C. for 1.5 hours. The solution then is added dropwise with stirring to ice water. The aqueous phase is decanted from the gummy product and fresh water is added. After 20 hours the gum solidifies and is crystallized from hexane-benzene (3:1) to obtain 6,7-dichloro-2-cyclopentyl-2,3-dihydro-5-methoxy-1H-inden-1-one, m.p. 116°-117° C.