Question

The increasing order of reactivity of the following compounds towards reaction with alkyl halides directly is :

(1) (B) < (A) < (D) < (C)
(2) (B) < (A) < (C) < (D)
(3) (A) < (C) < (D) < (B)
(4) (A) < (B) < (C) < (D)

• A. $1$
• B. $4$
• C. $2$
• D. $3$

Answer 1

The correct option is C $2$

The lone pair pair of electrons on N of compound A and B is delocalised with the carbonyl group to form resonating structures, whereas, in compound (C) & (D), lone pair is delocalised in benzene ring but it is readily available for nucleophilic reaction compare to others. Hence, A and B are less nucleophilic than C and D.

Since, in compound B, lone pair is delocalised between two carbonyl group, hence it is least nucleophilic than others.

Also, in compound C, the electron withdrawing group, CN reduce the electron density on N.

Hence, correct nucleophilic order is: