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What are the only exceptions to deactivating groups that are ortho-para directors?

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Final answer:

Halogens are exceptions to deactivating groups as ortho-para directors because they contribute to resonance despite their electronegativity.

Step-by-step explanation:

The exceptions to deactivating groups that are ortho-para directors in chemistry typically involve halogens such as fluorine, chlorine, bromine, and iodine. While halogens are electronegative and deactivate the benzene ring towards electrophilic aromatic substitution due to their inductive effect, they are still ortho-para directors. This is because halogens have lone pairs that can be donated into the π-system of the benzene ring, contributing to resonance stabilization of the intermediate carbocation formed during the substitution process, thus directing the incoming electrophile to the ortho and para positions rather than the meta position.

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