Question

Which of the following carbanion is most stable?

• A. Methyl
• B. Primary
• C. Secondary
• D. Tertiary

Answer 1

The correct option is A Methyl

$\underset{1^o}{\underset{\text{Methyl}\text{carbanion}}{C{H}_3^{-}}>R-C{H}_2^{-}>R-\underset{\underset{\underset{2^o}{R}}{|}}{C}{H}^{-}}>R-\underset{\underset{\underset{3^o}{R}}{|}}{\stackrel{\stackrel{R}{|}}{C^{-}}}|$

As the number of alkyl $\left(R\right)$ groups increases, the carbanion becomes more unstable because of the electron donating nature of the alkyl $\left(R\right)$ group.