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5446102 
Journal Article 
Kinetics of the Friedel-Crafts acylation of benzene with alkanoyl chlorides 
Hashimoto, I; Kawasaki, A; Ogata, Y 
1972 
Tetrahedron
ISSN: 0040-4020 
28 
217-225 
English 
The Friedel-Crafts acylation of benzene with some alkanoyl chlorides has been kinetically studied in ethylene dichloride. At higher initial concentration of the RCOCl-AlCl3 addition complex, simple second-order kinetics are observed, and the relative rates of studied alkanoyl chlorides fit Taft's equation with ϱ* of 3·26 and δ of 0·39. A sequence of reactivities, β-chloropropionyl > phenylacetyl > acetyl > propionyl > n-butyryl > isobutyryl > cyclohexanecarbonyl chloride, is observed at 10°. But at lower initial concentration of RCOCl-AlCl3 complex, the second-order rate constant increases with initial concentration of complex. A mechanism involving a pre-equilibrium in the formation of the complex between RCOCl and AlCl3 is presented and discussed.