Question

Rank the following radicals in order of decreasing stability.

Rank the following radicals in order of decreasing stability.

Answer 1

Concepts and reason

An organic (alkyl) radical is a highly reactive chemical species that contains a single unpaired electron in unhybridized p-orbitals.

It can be represented as a dot (). Organic radicals are classified as primary, secondary, or tertiary, based on the number of alkyl groups attached to the carbon-containing radical. The stability of organic radicals increases with the increasing alkyl substituents at radical carbons. It can be affect by the nature of substituents, resonance and inductive effect.

Fundamentals

The organic radicals can be classified based on the number of alkyl substituents present on the carbon radical.

Primary organic radicals:

Secondary organic radicals:

Tertiary organic radicals:

Resonance:

In a conjugated molecule, the lone pair of electrons or pi electrons move through sigma bonds within a molecule. It leads to different arrangements of electrons (resonance contributor) for the same molecules. It is called a resonance. For example,

Stability of organic radicals:

The stability of organic radicals increases with increasing substitution at the radical carbon. It can also be increased by resonance (more double bond conjugation is a more stable structure)

The primary radical is given below:

The secondary radical is given below:

The tertiary radical is given below:

The allylic radical is given below:

Ans: