Questions tagged [enolate-chemistry]
Enolates are anions derived from the deprotonation of carbonyl compounds. This tag must be used while dealing with the enolates or its derivatives including its resonance forms.
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Why aren't aldehydes more acidic than saturated alcohols?
Aldehydes (pKa ~17-20) and ketones (pKa >20) are worse acids than alcohols (pKa ~15-16). I have seen that the equilibrium of aldehydes (and ketones) with their hydrates greatly decreases pKa values ...
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Selective formation of enolates
I saw the following reaction on Modern methods of Organic Synthesis by Carruthers. The reaction is about the selective alkylation of trimethylsilyl enolates, and is shown below.
However, I have some ...
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Mechanism of deprotection of enol thioether
I was reading some enolate chemistry from Carruthers textbook and came across the selective alkylation of unsymmetrical ketones. The reaction involves blocking one alpha-position of the ketone using ...
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Reaction mechanism of enolate formation [closed]
In this reaction, KOtBu is supposed to be used to form an enolate first and then ethyliodide is added. I just can't figure out the reaction mechanism of this reaction, can someone help?
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how does enolate affect an elimination reaction?
From my class:
But why wouldn't the reaction proceed through this way, which makes more sense? Since the reaction above generates an enolate bearing a negative charge first, making the molecule less ...
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Aldol Cyclization Cascade Reaction between Two Ketones in Basic Alcoholic Solution
My professor gave a hint that the reaction scheme is a multiple carbonyl reaction which involves cyclization. He emphasizes that the reactivity of carbonyl compound in terms of C-H acidity and ...
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stereoselectivity in aldol reactions
in "Advanced Organic Chemistry, part B" fifth edition book, page:103, the authors compare between aldol reactions where 1-substituted nucleophile is used. They stated that when the 1-...
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Nucleophilicity of sterically hindered enolates
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Here $\ce{KH}$ obviously acts as a base, and forms the enolate from the ketone, which subsequently act as nucleophiles causing an SN2 reaction on the $\ce{CH3I}$. When this ...
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What is the reaction mechanism between acetophenone and ethyl phenylpropiolate to form a 2-pyrone?
I am looking for the mechanism of the following reaction (I believe it is a type of Michael reaction), which is in the textbook "Advanced Organic Chemistry Part B: Reaction and Synthesis" by ...
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Acidity of alpha hydrogens in enolate formation
I am interested in why the most right alpha hydrogen is removed to form the carbanion prior to intermolecular aldol condensation (2nd row first molecule).
Why is it that the alpha hydrogen from the ...
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Which of the following compounds possess more than one percent enol content? [closed]
Which of the following compounds possess more than one percent enol content?
I understood that stability of enols are dependent on the hydrogen bonding in the compounds. But here, what is the ...
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Why can't the N- end of the nitrile anion attack the alkyl halide in an SN2 fashion during an alkylation reaction when OH- can?
I'm reading my Clayden textbook and something keeps nagging me. It says that when we're carrying out alkylation reactions with an enol attacking an alkyl halide with strong base catalysis (with ...
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Selectivity in Thermodynamically-Driven Silyl Enol Ether Formation, and Optimistic Avoidance of Protecting Group Chemistry
I am aware of the regioselectivity of silyl enol ether formation at an unsymmetrical ketone under 'thermodynamic conditions'.
Does this selectivity extend to systems containing more than one ketone ...
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Regioselective enolate formation, choosing major and minor products
This question came in my organic chem assignment. The options highlighted are the answers.
The end carbon(adjacent to the carbonyl group) should have more acidic alpha-hydrogen and the alkene formed ...
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Mechanism of acid-catalyzed Robinson annulation?
My professor posed my organic chemistry class a challenge problem for bonus points and I've been racking my brain over the last three days trying to work it out and I want to know if my solution is ...
