Learning Objective: To learn about the three ways carbanion intermediates are generated.
Skill Level - Intermediate
Prerequisites:
Chapter: Reactive Intermediates
Sub-topic: Carbanion
Author's Note: Since, like most things in the universe where opposites exist, the carbanions, a negative counterpart of carbocations, were found much later in 1907. Post discovery, it remains a crucial intermediate to organic chemistry and is used to form various carbon-carbon or carbon–heteroatom bonds. In this section, I will cover different ways commonly used for carbanion formation, illustrated with the curved arrows how charge transfer resides on the carbon atom.
Formation of Carbanion
A) Heterolytic Bond Cleavage
The carbanions are formed due to heterolytic bond cleavage, a type of bond breaking.
In heterolytic bond cleavage, the two electrons covalent bond joining two atoms breaks unequally. Post breakage, the two bond electrons rest only with one atom (carbanion), leaving the other atom electron deficient.

The leaving group is usually a proton (H+), removed with the help of a strong base, enabling the formation of a carbanion. ......
If the leaving group is....
In reactions involving alkyl halides and...
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