Single Choice

Which of the following statement is not true about carbanions?

AStability of carbanions increases with increase in s- character of orbital
BElectron withdrawing groups like $$ -NO_{ 2 },\,-CN,\,\underset{/\,\,\,}{\overset{\backslash\,\,\,}C}=O$$ increase the stability of carbanions.
COrder of stability of carbanions is $$ 3^o\,>\,2^o\,>\,1^o $$
Correct Answer
DThe negativity charged carbon is $${ sp }^{ 3 }$$ hybridised and tetrahedral.

Solution

Increase in number of +I groups increases electron density and higher electron density on negatively charged carbon destabilizes the carbanion.
The tertiary carbanion has 3 +I group, secondary has 2 +I and primary has 1 +I group. Thus, the correct order of stability is $$1^{o}>2^{o}>3^{o}$$.
Thus given order of stability is incorrect.

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