Mannich reaction M.Pharmacy 1st Semester 2022 (2021-2022) Previous Year's Question Papers/Notes Download - HK Technical PGIMS

TABLE OF CONTENTS

• Introduction
• Reaction
• Mechanism
• Example
• Application Of mannich reaction

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INTRODUCTION

• When a ketone containing active hydrogen (enolizable ketone) undergo condensation
with formaldehyde (non-enolizable aldehyde ) and amine ( mostly Sec. Amine) in the
presence of HCL to form Beta-amino carbonyl compounds ( mannich base).
• This kind of Condensation reaction is Known as Mannich Reaction.
• In the Mannich reaction, primary or secondary amines or ammonia, are employed for the
activation of formaldehyde.
• The Mannich reaction is an example of nucleophilic addition of an amine to a carbonyl
group followed by dehydration to the Schiff base.

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REACTION

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MECHANISM OF MANNICH REACTION

• Step 1 Formation of Iminium ion.

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STEP 2 FORMATION OF CARBANION.
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STEP 3 COMBINATION OF CARBANION AND
IMINIUM ION.

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EXAMPLE

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APPLICATION OF MANNICH REACTION

1. Formation of Amino methyl derivatives form symmetrical and Unsymmetrical ketones.
2. Formation of Quaternary ammonium salts.
3. Formation of terminal Alkenes (Vinyl ketones).
4. Formation of Gramine (Amino alkyl indole).
5. Formation of Pyrrole derivatives.
6. Formation of Phenol derivatives.
7. Formation of 2- methyl Furan derivatives.

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FORMATION OF AMINO METHYL DERIVATIVES

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FORMATION OF QUATERNARY AMMONIUM SALTS

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FORMATION OF PYRROLE DERIVATIVES
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FORMATION OF PHENOL DERIVATIVES