Which of following reagents will furnish ambident nucleophile?

(A) $AgCN$
(B) $KCN$
(C) $AgNO_2$
(D) $KNO_2$

Choose the correct answer from the options given below:

(A), (B), (C) and (D)

The correct answer is Option (1) → (A), (B), (C) and (D)

An ambident nucleophile is a species that can attack an electrophile (e.g., alkyl halide) from two different atomic sites, potentially leading to different products.

• (A) AgCN: Provides CN⁻ in a partially covalent form (Ag bonded preferentially to C). The lone pair on N is available → attacks mainly through N to give alkyl isocyanide (major) + some nitrile. Hence, ambident behavior.
• (B) KCN: Highly ionic → provides free CN⁻ ion. CN⁻ can attack through C (major, giving alkyl cyanide/nitrile) or N (minor, isocyanide). Hence, CN⁻ is a classic ambident nucleophile.
• (C) AgNO₂: Partially covalent (Ag bonded to O). Lone pair on N is more available → attacks mainly through N to give nitroalkane (major) + some alkyl nitrite. Hence, ambident behavior.
• (D) KNO₂: Ionic → provides free NO₂⁻ ion. NO₂⁻ can attack through O (major, giving alkyl nitrite) or N (minor, nitroalkane). Hence, NO₂⁻ is an ambident nucleophile.