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Question
Arrange the following in the increasing order of their reactivity towards nucleophilic addition reaction:
C6H5COCH3, CH3-CHO, CH3COCH3
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Solution
Aldehydes are generally more reactive than ketones in nucleophilic addition reactions because of steric and electronic reasons. In case of ketones, aromatic ketones are more susceptible to nucleophilic attack than aliphatic ketones.
CH3COCH3 < C6H5COCH3 < CH3CHO
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CH3CHO, \[\begin{array}{cc}
\ce{(CH3)3C-C-CH3}\\
\phantom{....}||\\
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| (i) |  |
| (ii) |  |
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||\phantom{.........}\\
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