For the formation of phenylethanone from benzene: Name and explain the mechanism, write an overall equation and write an equation for the formation of the electrophile.
Overall equation:
C6H6 + CH3COCl ---> C6H5COCH3 + HCl
Equation for formation of the electrophile:
CH3COCl + AlCl3 ---> [CH3CO]+ + [AlCl4]-
Name of mechanism:
Electrophilic substitution
Explanation of mechanism:
The electron-deficient CH3CO+ electrophile ion is attacked by the delocalised pi electron system in the benzene ring breaking the aromaticity of benzene to form [C6H6COCH3]+. The residual proton may then be accepted by a residual chloride ion in the remaining [AlCl4]- to form the residual HCl product and re-form the AlCl3 catalyst and retain the aromaticity of the product.
