Aldehydes and Ketones - carbonyl compounds

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Aldehydes and Ketones - carbonyl compounds

• carbonyl group -
• structure, bonding and physical properties

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Review of methods of preparation of aldehydes and
ketones

• hydration of alkynes
• Friedel-Crafts acylation of aromatic compounds

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Overview of reactions of carbonyl compounds

• reduction to alcohols
• addition of organometallic reagents
• addition of oxygen, nitrogen, sulfur and
  phosphorus nucleophiles
• reduction of carbonyl to methylene (Clemmensen or
  Wolff-Kishner)

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Nucleophilic addition to carbonyls
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Nucleophilic addition to carbonyls
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Synthesis of Alcohols

• Reduction of Carbonyl Compounds

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Synthesis of Alcohols
Reduction of Carbonyl Compounds
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Synthesis of Alcohols
Reduction of Carbonyl Compounds
H2/cat., NaBH4, LiAlH4
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lithium aluminum hydride (LAH)
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sodium borohydride
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Synthesis of Alcohols Using Organometallic
Reagents
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Hydration of aldehydes and ketones
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An example
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Addition of alcohols hemiacetal and acetal
formation
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Addition of alcohols hemiacetal and acetal
formation

• hemiacetal
• or hemiketal

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Addition of alcohols hemiacetal and acetal
formation

• hemiacetal acetal

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Mechanism of acetal formation
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Mechanism of acetal formation
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An example
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Addition of ammonia and amines imine and
enamine formation
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Examples
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Examples
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Examples
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The Wittig Reaction
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An example
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The mechanism
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Mechanism, cont.
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Mechanism, cont.
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Mechanism, cont.
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Formation of cyanohydrins
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Example
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Reduction of carbonyls to alkanes

• Clemmensen reduction
• Wolff-Kishner reduction
• Desulfurization of thioketals

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Nucleophilic Addition to a,b-Unsaturated Carbonyls
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Nucleophilic Addition to a,b-Unsaturated Carbonyls

• Strong nucleophiles add 1,2
• kinetic control
• Weaker nucleophiles add 1,4
• thermodynamic control

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Nucleophilic Addition to a,b-Unsaturated Carbonyls
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Nucleophilic Addition to a,b-Unsaturated Carbonyls
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Nucleophilic Addition to a,b-Unsaturated Carbonyls
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Nucleophilic Addition to a,b-Unsaturated Carbonyls