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NEET levelSingle correct optionDifficulty 1 of 3o4131

3-Hydroxybutanal is heated with dilute aqueous alkali. The product is

Abut-3-enal
Bbutanal
Cbut-2-enal
Dbuta-1,3-diene

Answer: C

The base removes the alpha-hydrogen (acidic because it is next to

C = O

) to give an enolate. The enolate expels

OH X^{-}

by E1cB, giving the conjugated alkene

CH X_{3} - CH = CH - CHO

, but-2-enal.

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