The order of reactivity of the following compounds with PhMgBr is: (I) PhCOPh (II)CH3CHO(III) CH3COCH3
Correct answer: D. (II) > (III) > (I)
- A. (I) > (II) > (III)
- B. (III) > (I) > (II)
- C. (II) > (I) > (III)
- D. (II) > (III) > (I)
Explanation
Reactivity of carbonyl compounds with any nucleophile is based on the electrophilicity of the carbonyl carbon and steric crowding around it. Based on electrophilicity and crowding, CH3CHO is the most reactive. The least reactive would be PhCOPh due to excessive steric crowding.
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About Aldehydes and Ketones
Aldehydes and ketones contain the polar carbonyl group, but aldehydes are generally more readily oxidised and more reactive than ketones. Coverage includes preparation by oxidation or reduction routes, nucleophilic addition of reagents such as hydrogen cyanide and bisulfite, and tests that distinguish aldehydes from ketones.
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