Favorskii rearrangement is one the important reactions in organic chemistry. Let us have some prior understanding of its mechanism and its applications.
2. Outline
• Principle
• Some reactions
• Mechanism ( Cyclic Ketone )
• Mechanism ( Open chain Ketone )
• Applications
9/21/2013 11:30 AMPrepared by Sagar Divetiya
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3. Principle
• α-Halogenated ketone undergoes rearrangement in
the presence of a base like hydroxide, alkoxide or
amine to give a carboxylic acid or its derivative i.e.
ester, amide. The reaction is known as Favorskii
rearrangement.
• The halogen may be a chloride, bromide or iodide.
9/21/2013 11:30 AMPrepared by Sagar Divetiya
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4. 9/21/2013 11:30 AMPrepared by Sagar Divetiya
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Some
reactions
Ester
Ketone
Carboxylic acid
Carboxylic acid
Ester
Alkoxide
Hydroxide
α-halogenated
5. Mechanism ( Cyclic Ketone )
Cl O
H
Cl O
RO
O
RO
ORO
RO H
H
O
OR
9/21/2013 11:30 AMPrepared by Sagar Divetiya
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- H
- Cl
1 2 3
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6. Mechanism ( Open Chain Ketone)
9/21/2013 11:30 AMPrepared by Sagar Divetiya
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H X
O
R’ RO
X
O
R’ O
RO
O OR
RO H
O
OR
R’
R’R’
O OR
R’
Favorskii
Rearrangement
H
1 2 3
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