An enol ether is an alkene with an alkoxy substituent. The general structure is R₁R₂C = CR₃ − O − R₄ with R an alkyl or an aryl group. Enol ethers and enamines are so-called activated alkenes or electron rich alkenes because the oxygen atom donates electrons to the double bond by forming a resonance structure with the corresponding oxonium ion. This property makes them reactive substrates in certain organic reactions such as the Diels-Alder reaction. An enol ether can be considered the ether of the corresponding enolate, hence the name. Two simple enol ethers are ethyl vinyl ether and 2,3-dihydrofuran. An alkene in organic chemistry is an unsaturated hydrocarbon containing at least one carbon to carbon double bond. ... In chemistry, the alkoxyl group is an alkyl group linked to oxygen thus: R-O- In this function, R represents the alkyl group. ... In organic chemistry, a substituent is an atom or group of atoms subsituted in place of a hydrogen atom on the parent chain of a hydrocarbon. ... An Alkyl is a univalent radical containing only carbon and hydrogen atoms arranged in a chain. ... In the context of organic molecules, aryl refers to any member of the set of functional groups or substituents that are derived from a simple aromatic ring. ... An enamine is an unsaturated compound derived by the reaction of an aldehyde or ketone with a secondary amine followed by loss of H2O. Form Categories: Functional groups | Stub ... Resonance structures are diagrammatic tools in organic chemistry to symbolize resonant bonds between atoms in molecules. ... Organic reactions are chemical reactions between organic compounds. ... The Diels-Alder reaction is an organic chemical reaction (specifically, a cycloaddition) between a conjugated diene and a substituted alkene, commonly termed the dienophile to form a substituted cyclohexene system. ... Ether is the general name for a class of chemical compounds which contain an ether group — an oxygen atom connected to two (substituted) alkyl groups. ... Enol (or, more officially, but less commonly: alkenol) is an alkene with hydroxyl group on one of the carbon atoms of the double bond. ...