Page 60 - Org 3 theoritical book 2024-25

Clinical Pharmacy PharmD - 2024/2025 Level 2 Pharmaceutical Organic Chemistry-3 (PC 305)
Pyridine Derivatives

1) Pyridine-N-oxide (pyridine-1-oxide)

Pyridine-N-oxide is a very reactive compound and undergoes many types of

reactions which cannot be given with pyridine. The resonance structures of

pyridine-N-oxide are as follows:

+

+ + +
N N N N
O - O - O - O -

electron-
withdrawing nucleophilic attack
effect

-

+ + - + - +
N N N N
O - O O O
electron-
donating
effect electrophilic attack

Br / oleum Br
2
o
70 C +
N
+ O -
N
SO H
3
O - oleum / HgSO 4
o
240 C +
N
O -

2) Alkyl derivatives:

Methyl derivatives of pyridine are called as follows:

Monomethyl derivatives: picolines

Dimethyl derivatives : lutidines

Trimethyl derivatives : collidines