Question

a) 3-oxo butanoic acid treated with LiAlH4 gives?
b) 3-oxo butanoic acid treated with NaBH4 gives?
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Answer 1

Answer:

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

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Example

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Possible Mechanism

1) Deprotonation

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2) Nucleopilic attack by the hydride anion

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3) Leaving group removal

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4) Nucleopilic attack by the hydride anion

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5) The alkoxide is protonated