Question

• A. Piperidine>Pyridine>Pyrrole
• B. Pyrrole>Pyridine>Piperidine
• C. Pyridine>Piperidine>Pyrrole
• D. Pyrrole>Piperidine >Pyridine

Answer 1

Answer: (A)

Piperidine>Pyridine>Pyrrole

Answer 2

Explanation: The basicity of a compound depends on the availability of the lone pair of electrons on nitrogen for protonation. The order of basic strength is:

N(sp3, localized lone pair) > N(sp2, localized lone pair) > N(sp2, delocalized lone pair, aromatic).

1. Piperidine: Contains an sp3-hybridized nitrogen atom with a localized lone pair, making it the strongest base.
2. Pyridine: Contains an sp2-hybridized nitrogen atom with a localized lone pair, making it moderately basic.
3. Pyrrole: Contains an sp2-hybridized nitrogen atom with a delocalized lone pair due to its involvement in the aromatic ring, making it the least basic.

Thus, the order of basic strength is:

Piperidine > Pyridine > Pyrrole.
Thus the correct answer is Option 1.