The order of decreasing stability of the following carbanion... | CHEMISTRY - FUNDAMENTAL CONCEPTS IN ORGANIC REACTION MECHANISM | SolveeIt | Solveeit

Today, August 18

Question

The order of decreasing stability of the following carbanions is.

(i) $\left( CH_{3} \right)_{3}C^{-}$ (ii) $\left( CH_{3} \right)_{2}CH^{-}$

(iii) $CH_{3}CH_{2}^{-}$ (iv) $C_{6}H_{5}CH_{2}^{-}$

A

(i) > (ii) > (iii) > (iv)

B

(iv) > (iii) > (ii) > (i)

C

(iv) > (i) > (ii) >(iii)

D

(iii) > (ii) > (i) >(iv)

Answer

(iv) > (iii) > (ii) > (i)

Explanation

Solution

: Stability of carbanions decreases with increase in +I effect. +I effect is maximum in $\left( CH_{3} \right)_{3}C^{-}$ , followed by $\left( CH_{3} \right)_{2}CH^{-}$ and $CH_{3}CH_{2}^{-}.$ in $C_{6}H_{5}CH_{2}^{-},$ resonance effect increases the stability Hence, the order of stability is

(iv) > (iii) > (ii) > (i).