1. Pyridine And Its Reactions
M. Sc. II
S.M. Joshi College
Prof. Pawar A.A.

2. Aromatic Six-Membered-Ring Heterocycles

3. Pyridine reacts like a tertiary amine:
The pyridinium ion is a stronger acid than a typical
ammonium ion
Pyridine reacts like a tertiary amine:

4. Pyridine Is Aromatic
The nitrogen lone pair is not released into the aromatic system because it is perpendicular to the  system.
The nitrogen withdraws electrons by resonance, resulting in an electron-deficient ring system.

5. Pyridine undergoes electrophilic aromatic substitution at

7. The pyridine nitrogen is a meta director:

8. Pyridine is reactive toward nucleophilic aromatic substitution because of the presence of the electronegative nitrogen:

9. Pyridine undergoes nucleophilic aromatic substitution at
C-2 and C-4:

10. If the leaving groups at C-2 and C-4 are different, the
incoming nucleophile will preferentially substitute for
the weaker base:

11. Bromination and Oxidation of
Substituted Pyridine

12. Diazotization of Aminopyridine

13. The a-hydrogens of alkyl substituents can be removed by base to generate anionic nucleophiles:
Pyridine a-hydrogen acidity is similar to that of ketone a-hydrogens

14. Quinoline and isoquinoline are ring-fused pyridine derivatives:

15. Reactions of pyridine-based anionic nucleophiles:

16. Thank You