Solveeit Logo
Login

Question

Question: Number of deutorium (D) present in final product obtained on prolong treatment with NaOD/D₂O...

Number of deutorium (D) present in final product obtained on prolong treatment with NaOD/D₂O

A

6

B

9

C

10

D

5

Answer

10

Explanation

Solution

In basic conditions with NaOD/D₂O, deuterium exchange occurs at positions alpha to the carbonyl and at vinylic positions, especially under prolonged treatment. The structure is 4,5-dimethylcyclohex-2-en-1-one.

  1. Hydrogens alpha to the carbonyl:
    • C6 (CH₂): 2 hydrogens exchange for deuterium.
    • C2 (vinylic, alpha to carbonyl): 1 hydrogen exchanges for deuterium.
  2. Vinylic hydrogens:
    • C3 (vinylic, beta to carbonyl): 1 hydrogen exchanges for deuterium due to conjugation.
  3. Hydrogens on methyl groups:
    • The two methyl groups (at C4 and C5) have a total of 6 hydrogens. Under prolonged treatment, these can also be exchanged.

Total exchangeable hydrogens = 2 (from C6) + 1 (from C2) + 1 (from C3) + 6 (from methyl groups) = 10. Therefore, 10 deuterium atoms are present in the final product.