Search results
Results From The WOW.Com Content Network
However, enols can be stabilized kinetically or thermodynamically. [citation needed] Some enols are sufficiently stabilized kinetically so that they can be characterized. [citation needed] Diaryl-substitution stabilizes some enols. [12] Delocalization can stabilize the enol tautomer. Thus, very stable enols are phenols. [13]
In the protonation of an enolate ion, the kinetic product is the enol and the thermodynamic product is a ketone or aldehyde. Carbonyl compounds and their enols interchange rapidly by proton transfers catalyzed by acids or bases, even in trace amounts, in this case mediated by the enolate or the proton source.
Many carbonyl compounds exhibit keto–enol tautomerism. This effect is especially pronounced in 1,3-dicarbonyl compounds that can form hydrogen-bonded enols. The equilibrium constant is dependent upon the solvent polarity, with the cis -enol form predominating at low polarity and the diketo form predominating at high polarity.
By contrast, stable solutions of pure enolate ions are easily prepared from most carbonyl compounds by reaction with a strong base. Second, enolate ions are more reactive than enols and undergo many reactions that enols don't. Whereas enols are neutral, enolate ions are negatively charged, making them much better nucleophiles.
The loss of antiaromaticity can sometimes be the driving force of a reaction. In the following keto-enol tautomerization, the product enol is more stable than the original ketone even though the ketone contains an aromatic benzene moiety (blue). However, there is also an antiaromatic lactone moiety (green).
The Santa Ynez Reservoir, a 117-million-gallon water resource near the Pacific Palisades, was under renovation and empty when fires tore through the Los Angeles neighborhood last week and ...
Booze makers are getting an early hangover after the US surgeon general called for the addition of a warning label to alcoholic drinks. On Friday, shares of beer and alcohol giants sank across the ...
In organic chemistry an enol ether is an alkene with an alkoxy substituent. [1] The general structure is R 2 C=CR-OR where R = H, alkyl or aryl. A common subfamily of enol ethers are vinyl ethers, with the formula ROCH=CH 2. Important enol ethers include the reagent 3,4-dihydropyran and the monomers methyl vinyl ether and ethyl vinyl ether.