# Esters of catechol - Fries rearrangement

Esters of catechol undergo the Fries rearrangement

But one product is formed more than the other.

I believe it is due to the electron withdrawing nature of the $\ce{OCOCH3}$ group which prefers the attack on meta position.I was able to write a reaction mechanism for the product which is minor in this case. But I couldn't write one for the major product. I wonder how it is formed?

Does the minor product itself rearrange to give the major product or are both of the products formed directly in this reaction?

• Your products appear to have lost an acyl group compared to the reactants. Is this intentional? – bon Jul 9 '15 at 14:26
• The last step is hydrolysis after which an acyl group is lost. – yasir Jul 9 '15 at 15:20

The key step in the reaction is thought to involve the interaction of a lewis acid with a phenyl ester to generate an acylium ion ($\ce{[R-C=O]^+}$). Once the acylium ion is generated the reaction proceeds like any other electrophilic aromatic substituion. The phenolic oxygen is a strong ortho-para director, so both ortho- and para-products are produced by the same mechanism. The $\ce{OCOR}$ group does not play a role in "directing" the substitution pattern.