What compounds can form enolates?

What compounds can form enolates?

Some bases that have been used for enolate anion formation are: NaH (sodium hydride, pKa > 45), NaNH2 (sodium amide, pKa = 34), and LiN[CH(CH3)2]2 (lithium diisopropylamide, LDA, pKa 36). Ether solvents like tetrahydrofuran (THF) are commonly used for enolate anion formation.

What compounds Cannot form enolates?

q Since carbonyl compounds which do not have alpha hydrogens can not form an enolate, they cannot undergo the aldol reaction. Therefore the simplest aldehyde, methanal (formaldehyde) cannot undergo the aldol reaction.

Why are enolates more useful than enols?

Enolates are synthetically much more useful than enols (although they react analogously). Imine anions and eneamines are synthetic equivalents of enolate anions. By knowing the pKa values of the relevant acidic protons it is possible to predict suitable bases for forming the corresponding enolates.

What does LDA and THF do?

Ether solvents like tetrahydrofuran (THF) are commonly used for enolate anion formation. Because of its solubility in THF, LDA is a widely used base for enolate anion formation.

Can aldehydes form Enolates?

The reaction involves an aldehyde enolate reacting with another molecule of the aldehyde. Remember enolates are good nucleophiles and carbonyl C are good electrophiles. Since the pKa of an aldehyde is close to that of NaOH, both enolate and aldehyde are present simultaneously.

Are enols alcohols?

Enols are derivatives of vinyl alcohol, with a C=C-OH connectivity. Deprotonation of organic carbonyls gives the enolate anion, which are a strong nucleophile.

Can aldehydes form enolates?

Is LDA a stable base?

Lithium diisopropylamide (commonly abbreviated LDA) is a chemical compound with the molecular formula [(CH3)2CH]2NLi. It is used as a strong base and has been widely utilized due to its good solubility in non-polar organic solvents and non-nucleophilic nature.

Does LDA react with THF?

Ether solvents like tetrahydrofuran (THF) are commonly used for enolate anion formation. With the exception of sodium hydride and sodium amide, most of these bases are soluble in THF. Because of its solubility in THF, LDA is a widely used base for enolate anion formation.