Compound A on oxidation with `OsO_4//NaHSO_3` following by reaction with `HIO_4` gives hexane 1,6 - di al .The structure of compound A can be given as

Options

A.
B.
C.
D.

Answer

To determine the structure of compound A, we will follow the steps outlined in the problem statement.

### Step-by-Step Solution:

1. **Identify the Reaction Conditions**:
- The problem states that compound A is oxidized using `OsO4` followed by `NaHSO3`, and then reacts with `HIO4`.
- `OsO4` is known for oxidizing alkenes to form diols (glycols).

2. **Understanding the Final Product**:
- The final product after the reactions is hexane 1,6-diol. This indicates that the original compound A must have a structure that allows for the formation of two hydroxyl (OH) groups at the 1st and 6th carbon positions after the reactions.

3. **Determine the Structure of Compound A**:
- Since `OsO4` is used, compound A is likely an alkene. The presence of two hydroxyl groups after oxidation suggests that compound A should have a cyclic structure to allow for the formation of a six-membered ring during the reaction with `OsO4`.
- The most suitable candidate is cyclohexene, which is a six-membered ring containing a double bond.

4. **Reactions Involved**:
- When cyclohexene reacts with `OsO4`, it forms a cyclic osmate ester. Hydrolysis of this intermediate leads to the formation of 1,2-hexanediol (two hydroxyl groups on adjacent carbons).
- The subsequent reaction with `HIO4` cleaves the diol, leading to the formation of hexane 1,6-diol, which confirms that the structure of compound A must allow for this transformation.

5. **Conclusion**:
- Therefore, the structure of compound A is cyclohexene.

### Final Answer:
The structure of compound A is cyclohexene.

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