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35 Cards in this Set
- Front
- Back
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Draw a ketone-enolate-enol equilibrium
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Between enolate and enol, the equilibrium is mostly to the right
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What promotes enol formation?
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Acids
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What promotes enolate formation and what type of solvent is preferred?
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Bases promote enolate formation. Aprotic solvents are preferred to prevent protonation back to aldehyde/ketone or to enol.
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When starting with 100% of one enantiomeric ketone/aldehyde and enol/enolate formation is promoted, what is the ratio of enantiomers after?
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It will be 50:50 because the carbon can attack a proton from above or below.
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Mechanism?
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Mechanism?
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Enol
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Which product is preferred and why?
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The disubstituted one because a tertiary alkyl group is much easier to deprotonate with NaH
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What is LDA, how is it formed and why is it used?
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It is used because it will only monoalkylate enolates. You can also control whether or not kinetic enol are formed.
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How to protect and deprotect an alcohol?
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What is the synthesis for this?
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What are the conditions for forming a kinetic enol? Why does this work?
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LDA/THF/-78C
Because the compounds don't have much energy, LDA will attack the least hindered alpha carbon, becasue it is easier to approach. |
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What are the conditions for forming a thermodynamic enol?
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EtONa/EtOH/RT
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Mechanism?
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Enamines~ What are they good for?
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They are like more stable enols.
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What conditions do you use to hydrolyze enamines?
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H2O and H+
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