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18.15: Reductions of Ketones and Aldehydes

  • Page ID
    183104
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    Carbonyl Reduction Reactions

    Aldehydes and ketones can be partially reduced to alcohols with sodium borohydride or Raney nickel. Of course, LiAlH4 could be used in stead of NaBH4. However, LiAlH4 is a stronger reducing agent so some benefits of selectivity are lost. Depending on the presence of more than one functional group within a single molecule, reaction selectivity can be useful. Aldehydes and ketones can be fully reduced to alkanes the Wolff-Kishner or Clemmensen Reduction.

    ch 19 sect 15 example 1.png

    Hydride Reduction Mechanism

    The hydride reduction mechanism follows the pattern we have learned for other nucleophilic addition reactions.

    ch 19 sect 15 hydride mechanism.png

    Exercise

    27. Complete the reaction map below.

    ch 19 sect 15 exercise expanded.png

    Answer

    27.

    ch 19 sect 15 exercise solution.png

    Contributors and Attributions


    18.15: Reductions of Ketones and Aldehydes is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.

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