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12.8: Conversion of carboxylic acids to alcohols using LiAlH4

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    170523
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    Carboxylic acids can be converted to 1o alcohols using Lithium aluminum hydride (LiAlH4). Note that NaBH4 is not strong enough to convert carboxylic acids or esters to alcohols. An aldehyde is produced as an intermediate during this reaction, but it cannot be isolated because it is more reactive than the original carboxylic acid.

    General reaction

    1.jpg

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    Example

    3.jpg

    Possible Mechanism

    1) Deprotonation

    4.jpg

    2) Nucleophilic attack by the hydride anion

    supplement nuc attack hydride.svg

    3) Leaving group removal

    6.jpg

    4) Nucleophilic attack by the hydride anion

    7.jpg

    5) The alkoxide is protonated

    8.jpg

    Contributors


    12.8: Conversion of carboxylic acids to alcohols using LiAlH4 is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.

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