In the Fries rearrangement, phenyl acetate is heated with anhydrous to yield a mixture of ortho- and para-hydroxyacetophenone. What is the minimum number of stoichiometric equivalents of required per

Question

In the Fries rearrangement, phenyl acetate is heated with anhydrous $AlCl_3$ to yield a mixture of ortho- and para-hydroxyacetophenone. What is the minimum number of stoichiometric equivalents of $AlCl_3$ required per mole of ester to drive this specific reaction to completion, considering its complexation behavior?

Prashant Kotian · Accepted Answer

Correct answer: 1. Similar to Friedel-Crafts acylation, the Lewis acid strongly coordinates with the oxygen atoms of both the starting ester and the resulting ketone/phenoxide products. Because the catalyst is tied up in these stable coordination complexes and not efficiently regenerated during the reaction cycle, at least 1 full stoichiometric equivalent is required, rather than just a trace catalytic amount.

💡 Solution & Explanation

Practice 22,000+ questions like this