Answer:
If carbonyl oxygen of 4-hydroxypentanal is enriched with , then the oxygen label appears in the water .
Explanation:
- In the first step, -OH group at C-4 gives intramolecular nucleophilic addition reaction at carbonyl center to produce a cyclic hemiacetal.
- Then, one equivalent of methanol gives nucleophilic substitiution reaction by substituting -OH group in cyclic hemiacetal to produce cyclic acetal.
- If carbonyl oxygen of 4-hydroxypentanal is enriched with
, then the oxygen label appears in the water produced at the end of reaction.
- Full reaction mechanism has been shown below.
