Enamine
An enamine is an unsaturated compound derived by the condensation of an aldehyde or ketone with a secondary amine.[1][2] Enamines are versatile intermediates.[3][4]
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Condensation to give an enamine.[5]
The word "enamine" is derived from the affix en-, used as the suffix of alkene, and the root amine. This can be compared with enol, which is a functional group containing both alkene (en-) and alcohol (-ol). Enamines are considered to be nitrogen analogs of enols.[6]
If one of the nitrogen substituents is a hydrogen atom, H, it is the tautomeric form of an imine. This usually will rearrange to the imine; however there are several exceptions (such as aniline). The enamine-imine tautomerism may be considered analogous to the keto-enol tautomerism. In both cases, a hydrogen atom switches its location between the heteroatom (oxygen or nitrogen) and the second carbon atom.
Enamines are both good nucleophiles and good bases. Their behavior as carbon-based nucleophiles is explained with reference to the following resonance structures.
References [edit]
- ^ Clayden, Jonathan (2001). Organic chemistry. Oxford, Oxfordshire: Oxford University Press. ISBN 0-19-850346-6.
- ^ Smith, Michael B.; March, Jerry (2007), Advanced Organic Chemistry: Reactions, Mechanisms, and Structure (6th ed.), New York: Wiley-Interscience, ISBN 0-471-72091-7
- ^ Enamines: Synthesis: Structure, and Reactions, Second Edition, Gilbert Cook (Editor). 1988, Marcel Dekker, NY. ISBN 0-8247-7764-6
- ^ R. B. Woodward, I. J. Pachter, and M. L. Scheinbaum (1974), "2,2- (Trimethylenedithio)cyclohexanone", Org. Synth. 54: 39; Coll. Vol. 5: 1014
- ^ R. D. Burpitt and J. G. Thweatt (1968), "Cyclodecanone", Org. Synth. 48: 56; Coll. Vol. 5: 277
- ^ Imines and Enamines | PharmaXChange.info
