Question

The increasing order of basicity of the following compounds is:

• A. (d)<(b)<(a)<(c)
• B. (a)<(b)<(c)<(d)
• C. (b)<(a)<(c)<(d)
• D. (b)<(a)<(d)<(c)

Answer 1

The correct option is D (b)<(a)<(d)<(c)

Here, (c) is the most basic because its conjugate acid is stabilized by equivalent resonance. Out of (a) and (d), (d) is more basic due to +I effect. (b) is less basic than (a) and (d) because the $N$ atom is $s{p}^2$ hybridised.