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  • Alpha Halogenation of Enols and Enolates - Chemistry Steps
    The role of the acid is to promote a tautomerization of the carbonyl to the corresponding enol which is nucleophilic enough to react with the halogen Overall, the reaction is a substitution of H by a halogen on the ɑ carbon Let’s summarize these two parts of the acid-catalyzed halogenation mechanism below:
  • Alpha Halogenation - Chemistry LibreTexts
    Acid Catalyzed Mechanism Under acidic conditions the reaction occurs thought the formation of an enol which then reacts with the halogen Step 1: Protonation of the carbonyl Step 2: Enol formation Step 3: S N 2 attack Step 4: Deprotonation
  • Enol Reactions: Acid-Catalyzed Aldol, Halogenation, and . . .
    Enols are the key nucleophilic intermediate in halogenation, the acid-catalyzed aldol reaction, and the Mannich reaction Acid catalyzes keto-enol tautomerism; the alpha-carbon of the protonated carbonyl is considerably more acidic than that of the neutral aldehyde or ketone
  • Acid-Catalyzed Alpha-Halogentation Explained: Definition . . .
    What is the role of the enol tautomer in acid-catalyzed alpha halogenation? The enol tautomer plays a crucial role in acid-catalyzed alpha halogenation as it acts as the nucleophile in the reaction The enol is formed from the keto form of the carbonyl compound under acidic conditions
  • Enols and Enolates - Alpha Carbon Chemistry | Organic Chemistry 3
    The halogenation occurs through nucleophilic attack by a halogen source, such as bromine or chlorine, on the enol intermediate, followed by deprotonation to yield the alpha-halogenated carbonyl compound
  • Chapter 20: Enols and Enolates - Vanderbilt University
    Mechanism of α-halogenation goes through an acid bromide intermediate An acid bromide enolizes more readily than a carboxylic acid Mechanism is analogous to the α-halogenation of aldehydes and ketones The α-halo carboxylic acid can undergo substitution to give α-hydroxy and α -amino acids
  • Chapter 22 Alpha Substitution and Condensations of Enols and . . .
    Chapter 22 * Mechanism of Acid-Catalyzed α Halogenation The mechanism of acid-catalyzed halogenation involves attack of the enol form of the ketone on the electrophile halogen molecule Loss of a proton gives the haloketone and the hydrogen halide


















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