Question

10. Chlorine substituent is
a) o,p- director b) m-director c) both (a) and (b) ) None of these​

Answer 1

Answer:

It’s one thing to learn about electrophilic aromatic substitution reactions of benzene itself. But once you move beyond benzene, that’s when things start getting really interesting.

Today we’ll describe the two main patterns by which substituents “direct” electrophilic aromatic substitution. In one pattern, substituents direct the reaction to give either the “ortho” (1,2) or “para” product, with a slight preference for “para” (1,4). In the second pattern, a different family of substituents direct the reaction to give primarily the “meta” (1,3) product.

Table of Contents

ortho-, para- Directors

meta- Directors

How Well Do “ortho-, para” And “meta“- Directors Correlate With “Activating” and “Deactivating” Groups?

The Key To Understanding ortho-, para- Directors And meta- Directors Is To Understand The Stability of The Carbocation Intermediate

1. ortho-, para- Directors

Here’s a fascinating observation.

Start with a monosubstituted benzene. Then perform some kind of electrophilic aromatic substitution (nitration, halogenation, sulfonylation – turns out it doesn’t matter).

Two important reaction patterns are observed.

It’s important to note that these two patterns are wholly a function of the substituent and not the reaction itself.

In one pattern, ortho- and para– products dominate, and the meta- product is an extremely minor byproduct.