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Here is my proposed mechanism, something tells me that the intramolecular deprotonation happens after, and that this is not concerted. Is my mechanism correct? My[![Friediel Crafts Acylation mechanism

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    $\begingroup$ Don’t draw it concerted. It is a stepwise process; the attack of the aromatic electrons onto the electrophile first with a delocalised carbocation as intermediate followed by deprotonation and rearomatising. $\endgroup$ – Jan May 2 '16 at 12:58
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The reactivity of acid chlorides and acid anhydrides are actually quite similar. It may be helpful for you to think of an acid anhydride like this:

Comparison between anhydride and acyl chloride

When we do, the acylation reaction is almost identical to that of an acid chloride, where an acylium cation $\ce{R-C#O+}$ is generated:

Acylation mechanism

The subsequent proton exchange restores aromaticity:

Proton exchange

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