Leaving group

Definition

A leaving group in organic chemistry is an atom or group that detaches from the parent molecule during a nucleophilic substitution (SN2) reaction, forming a lone pair or negative ion. The ease with which a leaving group departs affects the rate and success of the reaction.

Related terms

Nucleophile:

A chemical species that donates an electron pair to an electrophile to form a chemical bond in relation to reaction mechanisms.

SN2 Reaction:

A type of nucleophilic substitution where a bond forms and a bond breaks simultaneously, resulting in the inversion of configuration at the carbon atom.

Electrophile:

An electron-deficient atom or molecule that tends to accept an electron pair from a nucleophile during chemical reactions