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I've just started with EAS. I wanted to write down a mechanism for acylation of a cyclic anhydride (for some reason the formation of the carbocation is not given in my textbook). So I wish to know whether this mechanism is correct or now. Since this is my first attempt at writing one, I don't know whether it's correct.
The reaction:
What I came up with:
The mechanism shown in the question seems reasonable enough to me. I would note that ring opening before the attack on the $\pi$-system is likely, but not absolutely necessary. Loss of $\ce{AlCl3}$ may not occur until workup. Direct proton transfer seems unlikely, but is a inconsequential detail. Note however, that the electron pushing arrow is drawn opposite to what it needs to be for that transfer.
Your mechanism is almost correct. In your first intermediate, you have a red arrow in the wrong place. Since this ring is opening up, you want the arrow showing movement of the ring electrons (those between the lower carbonyl and the ring oxygen). Ideally, you would show those electrons becoming the new CO double bond of the aluminum carboxylate.
