Pyrrole is less basic than pyridine. The orbital having the lone pair ...
Pyridine, on the other hand, already has a stable conjugated system of 3 double bonds in the aromatic hexagonal ring, like benzene. Hence the lone pair electrons on the N atom in pyridine can be easily donated to a H+ ion or a Lewis acid. Therefore, pyridine is a stronger base than pyrrole.
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Pyrrole is less basic than pyridine. The orbital having the lone pair ...
Explanation:
Introduction:
Pyrrole and pyridine are both heterocyclic aromatic compounds that contain nitrogen. Pyrrole contains a five-membered ring with four carbon atoms and one nitrogen atom, while pyridine contains a six-membered ring with five carbon atoms and one nitrogen atom. The lone pair of electrons on the nitrogen atom in both pyrrole and pyridine is responsible for their basicity.
Less basic nature of pyrrole:
Pyrrole is less basic than pyridine because the lone pair of electrons on the nitrogen in pyrrole is involved in delocalization with the aromatic ring. This delocalization of electrons makes the lone pair less available for donation to a proton, reducing the basicity of pyrrole.
Orbital having the lone pair of electrons on nitrogen in pyrrole:
The lone pair of electrons on nitrogen in pyrrole is in an sp2 hybrid orbital. In pyridine, the lone pair of electrons on nitrogen is in an sp3 hybrid orbital. The sp2 hybrid orbital has a higher percentage of s-character than the sp3 hybrid orbital, making it more electronegative and less basic. Additionally, the sp2 hybrid orbital is involved in the delocalization of electrons with the aromatic ring, further reducing the basicity of pyrrole.
Pyrrole is less basic than pyridine. The orbital having the lone pair ...
Correct answer will be b because nitrogen in pyrrole is sp2 hybridise and lone pair on nitrogen are used to form pi bond so it will be definitely in p orbital