What does enamine mean?
An enamine is an organic compound in which an amino group is attached to one of the carbons of a carbon–carbon double bond, making it the nitrogen-containing counterpart of an enol. The name itself encodes this relationship, combining 'ene' from alkene and 'amine'. Enamines are not typically isolated as stable end products; instead, they are prized as reactive intermediates in organic synthesis. Formed when a secondary amine condenses with an aldehyde or ketone, enamines act as nucleophiles at the carbon next to nitrogen, allowing chemists to alkylate or acylate carbonyl compounds under mild conditions — most famously through the Stork enamine reaction. They also play a central role in modern organocatalysis, including proline-catalysed asymmetric reactions. Though strictly a specialist term of laboratory chemistry, the word occasionally surfaces in science journalism covering advances in drug synthesis and green catalysis.
nounAn organic compound containing a carbon–carbon double bond directly adjacent to an amino group, i.e. an alkene substituted with an amine; enamines are the nitrogen analogues of enols and are important reactive intermediates in organic synthesis.
- An organic compound in which an amino group is bonded to an alkene carbon — a C=C double bond adjacent to nitrogen, formally the nitrogen analogue of an enol.
"The chemist formed an enamine in situ from cyclohexanone and pyrrolidine to carry out the alkylation."
"The Stork enamine reaction exploits the nucleophilicity of enamines to alkylate carbonyl compounds under mild conditions."
"Because enamines hydrolyse readily back to their parent ketone and amine, they are usually generated and used in a single step."
Standard regular plural; countable, as in references to multiple such compounds.
"Chiral secondary amines generate enamines that react stereoselectively with electrophiles."
Enamines are the unsung heroes of organic chemistry — the Stork enamine reaction built around them won Gilbert Stork a place among the giants of synthetic chemistry.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of enamine
The word enamine was coined in the early twentieth century by blending 'ene', the suffix denoting a carbon–carbon double bond in alkene nomenclature, with 'amine', denoting a nitrogen-bearing compound. Both elements trace back further: 'amine' derives from 'ammonia', ultimately from Latin sal ammoniac via Greek, while 'ene' comes from the '-ene' ending used systematically for unsaturated hydrocarbons. The term arose alongside related coinages such as 'enol' (alkene plus alcohol), reflecting the systematic naming of functional-group analogues in organic chemistry.
How enamine is actually used
A technical term used almost exclusively in organic and physical organic chemistry. It appears in textbooks, journal articles, and advanced coursework rather than everyday language.
Easily confused with enamine
An imine has a carbon–nitrogen double bond (C=N), whereas an enamine has a nitrogen attached by a single bond to a carbon that participates in a carbon–carbon double bond.