Which of the following compounds produces an optically inactive compound on hydrogenation?

Options

A.
B.
C.
D.

Explanation

To determine which of the given compounds produces an optically inactive compound upon hydrogenation, we will analyze each compound step by step.

### Step 1: Understanding Optical Activity
Optical activity is determined by the presence of a plane of symmetry in a molecule. If a molecule has a plane of symmetry, it is considered optically inactive. Conversely, if it lacks a plane of symmetry, it is optically active.

### Step 2: Analyzing Each Compound
We will analyze each compound provided in the options to see if the product formed after hydrogenation has a plane of symmetry.

#### Compound 1:
- Structure: Alkene with two methyl groups on one side and a hydrogen on the other.
- Upon hydrogenation, the double bond is converted to a single bond.
- Check for plane of symmetry: The left side has two methyl groups, while the right side has a hydrogen. Thus, there is no plane of symmetry.
- Conclusion: This compound is optically active.

#### Compound 2:
- Structure: Similar to the first compound but arranged differently.
- Upon hydrogenation, the double bond is converted to a single bond.
- Check for plane of symmetry: The left and right sides are still not identical.
- Conclusion: This compound is also optically active.

#### Compound 3:
- Structure: Contains two methyl groups on either side of a double bond.
- Upon hydrogenation, the double bond is converted to a single bond.
- Check for plane of symmetry: If we draw a plane through the center of the molecule, both sides are identical (two methyl groups on both sides).
- Conclusion: This compound has a plane of symmetry and is optically inactive.

#### Compound 4:
- Structure: Similar to the previous compounds but with a different arrangement.
- Upon hydrogenation, the double bond is converted to a single bond.
- Check for plane of symmetry: The left and right sides are not identical.
- Conclusion: This compound is optically active.

### Final Conclusion
From the analysis, **Compound 3** is the only one that produces an optically inactive compound upon hydrogenation due to the presence of a plane of symmetry.