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Question
Give plausible explanation for the following:
Cyclohexanone forms cyanohydrin in good yield but 2, 2, 6 trimethylcyclohexanone does not.
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Solution
Due to the presence of three methyl groups at α-places, nucleophilic attack of CN– ions does not occur. This steric hindrance is absent in cyclohexane. Hence, nucleophilic attack of CN– ions occurs quickly. Hence, cyclohexanone cyanohydrin is obtained in good yield.
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