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The Mannich reaction is one of the few three-component reactions in organic chemistry. In this reaction, a ketone, an aldehyde and an amine react together under acid catalyzed conditions to form the final product. The mechanism involves the following steps: 1. Following initial protonation of the carbonyl oxygen, nucleophilic attack by the amine forms a protonated carbinolamine 1; 2. Proton transfer and elimination of water forms iminium ion 2; 3. The enol form of the ketone attacks the iminium ion to form adduct 3; 4. Deprotonation of adduct 3 leads to the final product. Write out the mechanism on a separate sheet of paper and then draw the structure of iminium ion 2.

User Bector
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Answer:

Step 1, formation of the iminium ion

2) enol reaction with iminium ion to form beta-amino enone

Step-by-step explanation:

Please find attached the detailed reaction mechanism and the structure of iminium ion separately

The Mannich reaction is one of the few three-component reactions in organic chemistry-example-1
The Mannich reaction is one of the few three-component reactions in organic chemistry-example-2
User Chrispitzer
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