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Questions
Why is the α-hydrogens of aldehydes and ketones are acidic in nature?
Account for the following:
The alpha (α)-hydrogens of aldehydes and ketones are acidic in nature.
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Solution
Because of the strong electron-withdrawing nature of the carbonyl groups and the resonance stabilisation of the conjugate base, aldehydes and ketones are acidic in nature.
| \[\begin{array}{cc} \ce{R}\phantom{..........}\\ \backslash\phantom{........}\\ \ce{C = O}\\ /\phantom{........}\\ \ce{H}\phantom{..........}\\ \end{array}\] |
\[\begin{array}{cc} \ce{R}\phantom{..........}\\ \backslash\phantom{........}\\ \ce{C = O}\\ /\phantom{........}\\ \ce{R}\phantom{..........}\\ \end{array}\] |
| Aldehyde | Ketone |
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RELATED QUESTIONS
What is meant by the following term? Give an example of the reaction in the following case.
Aldol
Which of the following compounds would undergo aldol condensation, which the Cannizzaro reaction and which neither? Write the structures of the expected products of aldol condensation and Cannizzaro reaction.
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How will you convert ethanal into the following compound?
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Why are carboxylic acids more acidic than alcohols or phenols although all of them have hydrogen atom attached to a oxygen atom \[\ce{(-O-H)}\]?
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