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What is a carbocation? How to identify carbocation? Explain the types with examples.

A carbocation is a positively charged, electron-deficient carbon atom that acts as a reactive intermediate in many organic reactions.

 

What is a carbocation with examples

 

The carbon at the positive center of the carbocation is electron deficient and has only 6 valence electrons instead of the preferred 8. As a result, a carbocation can form only three covalent bonds; therefore, it is trivalent.

 

shape and hybridization of carbocation

 

The central carbon is sp2 hybridized. The three substituents of carbon are oriented to the three corners of an equilateral triangle. Therefore, the geometry of the carbocation is trigonal planar, and the bond angle between the substituent is 1200.

Based on the number of alkyl substituents on the central carbon, carbocations are of three types: Primary, secondary, and tertiary.

 

Primary Carbocation:

The central, positively charged carbon is bonded to one alkyl substituent, and the other two are H atoms.

For example,

What is a primary carbocation

 

Secondary Carbocation:

The central carbon in a secondary carbocation is bonded to two alkyl substituents and one H atom.

For example,

What is a secondary carbocation

 

Tertiary Carbocation:

The positively charged, trivalent carbon in a tertiary carbocation is bonded to three alkyl substituents.

For example,

What is a tertiary carbocation

 

Methyl Carbocation:

The central carbon in a methyl carbocation has no alkyl substitutions. All three substituents are H atoms. It is the simplest, highly unstable carbocation.

What is a methyl carbocation?

 

Related Reading:

Definition of a Carbocation 

Difference Between Carbocation and Free Radical

Difference Between Carbocation and Electrophiles

Difference Between Carbocation and Carbanion

Reactive Intermediates
Organic Chemistry - Drawing Structures, Concepts, and Examples

Organic Chemistry Tutorials - CurlyArrows Premium

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