Question

Find out the correct order of basic strength among the given compounds.

• A. $III>IV>I>II$
• B. $IV>III>I>>II$
• C. $IV>III>II>I$
• D. $IV>I>II>>III$

Answer 1

The correct option is A $III>IV>I>II$

Basic strength can be attributed to the lone pair availability for donation.

(III) Acetimidamide is the most basic due to increase in electron density at nitrogen by other nitrogen in conjugation.
(IV) Lone pair of nitrogen in phenylmethanamine is available to donate.
(I) Lone pair of nitrogen in aniline is involved in resonance and is less available.
(II) Lone pair of nitrogen in acetamide is involved in resonance. The delocalisation is strong so it is the least basic