What does nucleophilic mean?
Nucleophilic is a technical adjective used in chemistry to describe a species with an affinity for electrons. More specifically, a nucleophilic atom, ion, or molecule can donate a pair of electrons to an electrophilic centre, often the positively polarized carbon of a carbonyl group or another carbon bonded to a leaving group. The term is central to descriptions of reactions such as nucleophilic substitution and nucleophilic addition. It may also characterize catalysts that promote reactions by increasing the nucleophilicity of a reactant. The word is not a general synonym for “attractive” or “friendly”; outside chemistry, its use is uncommon and usually technical or metaphorical. Its counterpart, electrophilic, describes species that accept an electron pair.
adjectiveHaving a strong affinity for electrons and capable of donating an electron pair in a chemical reaction. In organic chemistry, nucleophilic species are described as attacking an electrophilic centre.
- Chemically having an affinity for electrons and able to donate an electron pair to an electrophilic centre.
"The hydroxyl group acts as a nucleophile in the substitution reaction."
"The reaction proceeded through a nucleophilic attack on the carbonyl carbon."
"Many negatively charged ions are highly nucleophilic."
Nucleophilic comes from the same roots as nucleus and the Greek for “loving,” reflecting the electron-loving character of these chemical species.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of nucleophilic
The word is formed from Latin nucleus, meaning “kernel” or “nut,” and the combining form -philic, derived from Greek philos, meaning “loving.” The same Latin root gives nuclear and nucleate, while the related noun nucleophile denotes an electron-pair-donating species.
Related word forms
How nucleophilic is actually used
This is primarily a technical chemistry term. It is usually applied to an atom, ion, molecule, or functional group that donates an electron pair, especially in substitutions and additions. Its opposite is electrophilic.
Easily confused with nucleophilic
A nucleophilic species donates an electron pair, whereas an electrophilic species accepts one.