Question

Which of the following compounds have higher enolic content than keto content?
A.

B.

C.

D.

Answer 1

Hint: Generally the ketone compounds exhibit the conversion of keto form to enol form through keto-enol tautomerism. To exhibit keto-enol tautomerism the carbonyl compound should contain alpha hydrogen atoms in it.

Complete Solution :
- In the question it is given that which compound shows high enolic content when compared to keto form among the given options.
- In the given options all the compounds exhibit keto-enol tautomerism but we have to find which compound will show high enoilc content when compared to keto form.
- The keto-enol tautomerism of all the given options is as follows.
- The keto-enol tautomerism Option A is as follows.

- The keto-enol tautomerism Option B is as follows.

- The keto-enol tautomerism Option C is as follows.

- The keto-enol tautomerism Option D is as follows.

- The option B will show high enolic content due to the presence of hydrogen bond between the alcohol and ketone.
- The presence of hydrogen bond will make high enolic content in the compound B and it is as follows.

- The presence of the hydrogen bonding is the reason behind the high enolic content in option C.
So, the correct answer is “Option C”.

Note: Generally the keto form is more stable at room temperature. But few compounds will exhibit high enolic content at room temperature due to the presence of intramolecular hydrogen bonding means the hydrogen bond is going to form internally in the molecule itself.