Aromaticity

Question 1

Despite their – I effect, halogens are o- and p-directing in haloarenes. Explain.

Answer 1

Halogens on benzene rings have a -I and a +R effect. The -I effect deactivates the ring, but the +R effect increases the electron density on ortho and para positions. Hence, halogens are ortho and para directing.

Question 2

How is Benzene more stable than

Question 3

Which Inductive effect groups decrease reactivity?

Answer 3

The +I groups increase the electron density at carbonyl carbon. Hence their reactivity towards nucleophiles decreases.

Question 4

Why is benzene not a cyclohexatriene?

Answer 4

However, the structure of benzene shows that all the bonds have the same length, and so cyclohexa-1,3,5-triene can’t be used to describe this structure as it has both double and single bonds which vary in length.

Question 5

Which Director are they
(I)CH3

Answer 5

(I)Ortho

Question 6

What do Activators do? Are they EWG or EDG’s?

Answer 6

They make Atom stable thus decreasing the Energy of molecule as a a whole.
EDG

Question 7

Why are activators classified into weak and strong?

Answer 7

Strong activators have lone pairs and if they battle, then the directors of strong group is where the incoming attacking molecule will go

Question 8

Use of Anhy AlCl3

Answer 8

It is used as a catalyst for halogenation of aromatic hydrocarbons and Friedel crafts alkylation and acylation reactions.