Question

The correct order of decreasing basic strength of the given amines is:

Options

• N-methylaniline > benzenamine > ethanamine > N-ethylethanamine

• N-ethylethanamine > ethanamine > benzenamine > N-methylaniline

• N-ethylethanamine > ethanamine > N-methylaniline > benzenamine

• Benzenamine > ethanamine > N-methylaniline > N-ethylethanamine

Answer 1

N-ethylethanamine > ethanamine > N-methylaniline > benzenamine

Explanation:

The stability of the conjugate acid formed after protonation and the availability of the lone pair of electrons on the nitrogen atom are the determinants of the fundamental strength of amines. The basicity of aqueous solutions is influenced by factors such as the inductive effect, steric effect, and solvation effects. Alkyl groups enhance the basic potency of amines, while the phenyl group decreases their basicity through resonance.

Therefore the correct order of decreasing basic strength of amines is:

N-ethylethanamine > ethanamine > N-methylaniline > benzenamine