Substitution reaction

Chemical reaction in which one functional group in a compound is replaced by another

A substitution reaction (also known as single displacement reaction or single substitution reaction) is a chemical reaction during which one functional group in a compound is replaced by another functional group. Substitution reactions are of prime importance in organic chemistry. Substitution reactions in organic chemistry are classified either as electrophilic or nucleophilic depending upon the reagent involved, whether a reactive intermediate involved in the reaction is a carbocation, a carbanion or a free radical, and whether the substrate is aliphatic or aromatic.

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