Question

The stability of carbanions in the following

i) $RC\equiv \stackrel{\ominus }{C}$

ii)

iii) $R_{2}C=\stackrel{\ominus }{CH}$

iv) $R_{3}C-\stackrel{\ominus }{C{H}_2}$

is in the order of

• A. (i) > (ii) > (iii) > (iv)
• B. (ii) > (iii) > (iv) > (i)
• C. (iv) > (ii) > (iii) > (i)
• D. (i) > (iii) > (ii) > (iv)

Answer 1

The correct option is A

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

The carbanion with more s-character is more stable. Thus, the order of stability is

$RC\equiv \stackrel{\ominus }{C}>C_6{H}_5^{\ominus }>R_{2}C=\stackrel{\ominus }{CH}>R_{3}C-\stackrel{\ominus }{C{H}_2}$