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Electrophilic aromatic substitution of furan favors addition to the 2-position because the intermediate cation is more stable than addition to the 3-position. Draw the mechanism arrows for the Friedel-Crafts acylation of furan. In steps 1-3 draw the curved arrows to show the formation of the acyliumion electrophile and acylation of furan. In steps 4 and 5 draw all resonance structures for the intermediate cation, then showing reaction of the last resonance structure with FeCl4 to generate the final product. Make sure to draw lone pairs of electrons for all species and nonzero formal charges.

User Harrakiss
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Answer:

See picture below

Step-by-step explanation:

In the attached picture, you have the mechanism of all this reaction.

In the first step, as this is Friedel Craft acylation, we need to use either AlCl₃ or FeCl₃. So, this compound (I will use FeCl₃) will attach to the Chlorine group of the CH₃COCl.

In the second step, the whole CH₃CO is attached to the furan, because of the attack of the double bond of the ring.

After this, it occurs several resonance structure, to give a more stable structure, and the Hydrogen in the 2 position is substracted to give the final product of acylation.

Hope this helps.

Electrophilic aromatic substitution of furan favors addition to the 2-position because-example-1
User Mdarwi
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