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alpha-carbon chemistry

9 videos
5D: Aldol condensations are one of the most important, frequently seen reactions in biochemistry. In fact, the very first reaction of the Krebs (TCA) cycle is an aldol condensation in which acetyl CoA condenses with oxaloacetate, forming citrate. You will learn the mechanism of these reactions formed as we extend this concept to predict the products of aldol condensations.

Keto-enol tautomerization

VIDEO 11:29 minutes
Mechanisms for acid and base catalyzed keto-enol tautomerization. By Jay.

Enolate formation from aldehydes

VIDEO 6:12 minutes
How to form enolates from aldehydes using sodium ethoxide and sodium hydride

Enolate formation from ketones

VIDEO 10:18 minutes
Forming enolates from ketones using LDA and sodium ethoxide

Kinetic and thermodynamic enolates

VIDEO 8:19 minutes
How to form different enolates from ketones

Aldol condensation

VIDEO 11:23 minutes
Base-catalyzed mechanism for aldol addition and aldol condensation

Mixed (crossed) aldol condensation

VIDEO 9:25 minutes
How to find the product of a mixed (crossed) aldol condensation

Mixed (crossed) aldol condensation using a lithium enolate

VIDEO 9:01 minutes
How to direct a mixed aldol condensation using a lithium enolate

Retro-aldol and retrosynthesis

VIDEO 11:13 minutes
How to think about the aldol condensation using retrosynthesis

Intramolecular aldol condensation

VIDEO 12:02 minutes
How to determine the product of an intramolecular aldol condensation