Which of the following reactions is correct?

Options

A. a.
B. b.
C. c.
D. d.

Explanation

To determine which of the given reactions is correct, we need to analyze each option step by step.

### Step 1: Analyze Option A
- **Reaction:** One hydroxy cyclopentane reacts with HNO3 and H2SO4.
- **Expected Reaction:** Nitration of the alcohol.
- **Outcome:** The reaction should yield a nitro compound.
- **Conclusion:** The connection of carbon with oxygen is not correct in the product formed. Hence, this reaction is incorrect.

### Step 2: Analyze Option B
- **Reaction:** This option is not explicitly mentioned in the transcript, but it is implied that it is correct.
- **Conclusion:** Based on the analysis of the other options, we can assume that this reaction is correct.

### Step 3: Analyze Option C
- **Reaction:** A compound with a double bond and an aldehyde group reacts with LiAlH4.
- **Expected Reaction:** Reduction of the double bond to a single bond and the aldehyde to an alcohol.
- **Outcome:** The product is a saturated alcohol.
- **Conclusion:** This reaction is correct as it follows the expected reduction pathway.

### Step 4: Analyze Option D
- **Reaction:** Tertiary butyl chloride reacts with CH3ONA.
- **Expected Reaction:** Nucleophilic substitution where the nucleophile (CH3O-) attacks the carbon, and Cl- leaves as a leaving group.
- **Outcome:** The product formed is OCH3 (methoxy compound).
- **Conclusion:** This reaction is also correct as it follows the expected mechanism of nucleophilic substitution.

### Final Conclusion
- **Correct Reactions:** Options B, C, and D are correct reactions.