Acetyl chloride → 5,8-Dimethoxy-2-acetyl-3,4-dihydronaphthalene

反応式

[CH3:1][O:2][C:3]1[CH:12]=[CH:11][C:10]([O:13][CH3:14])=[C:9]2[C:4]=1[CH2:5][CH2:6][CH:7]=[CH:8]2.[C:15](Cl)(=[O:17])[CH3:16].[Cl-].[Cl-].[Cl-].[Al+3]>>[C:15]([C:6]1[CH2:7][CH2:8][C:9]2[C:4](=[C:3]([O:2][CH3:1])[CH:12]=[CH:11][C:10]=2[O:13][CH3:14])[CH:5]=1)(=[O:17])[CH3:16]

参加物

反応物 3

HCID 6367Acetyl chloride

HCID 2676515,8-Dimethoxy-1,2-dihydronaphthalene2 回

HCID 6451240Aluminum(III) Chloride2 回

生成物 1

HCID 110642935,8-Dimethoxy-2-acetyl-3,4-dihydronaphthalene

実験手順

In spite of the fact that in literature the attempts of acylating the compound II were reported as fruitless or non interesting because of the low yields, the 5,8-dimethoxy-3,4-dihydronaphthalene II is treated with acetyl chloride in the presence of an excess of aluminium trichloride, preferably 5-9 moles of aluminium trichloride for one mole of acyl chloride, at the temperature of −35°+25° C., preferably at 0° C. After the usual work-up and crystallisation with ethyl acetate, the product, 2-acetyl-5,8-dimethoxy-3,4-dihydronaphthalene is obtained in yields higher than 70%.