Which one of the following -compounds does not react with nitrous acid ? .

Options

A.
B.
C.
D.

Explanation

To determine which compound does not react with nitrous acid (HNO2), we need to identify the presence of alpha hydrogen atoms in each compound. Compounds that lack alpha hydrogen will not undergo a reaction with nitrous acid.

Let's analyze the compounds step by step:

### Step 1: Identify the Compounds
We have four compounds to analyze. Let's denote them as:
- A: CH3CH2CH2NO2
- B: CH3CH2C(CH3)NO2
- C: (Compound with no alpha hydrogen)
- D: (Another compound)

### Step 2: Analyze Compound A (CH3CH2CH2NO2)
- This compound has the structure: CH3-CH2-CH2-NO2.
- The alpha hydrogen is present on the carbon adjacent to the nitrogen (the CH2 group).
- When treated with nitrous acid, the alpha hydrogen will be replaced by the nitroso group (ONO).
- **Product**: CH3-CH2-CH(NO2)-OH (and possibly tautomerization).

### Step 3: Analyze Compound B (CH3CH2C(CH3)NO2)
- This compound has the structure: CH3-CH2-C(CH3)-NO2.
- The alpha hydrogen is present on the CH2 group adjacent to the nitrogen.
- Similar to compound A, the alpha hydrogen will be replaced by the nitroso group.
- **Product**: CH3-CH2-C(CH3)(NO2)-OH.

### Step 4: Analyze Compound C
- This compound does not have an alpha hydrogen (for example, it could be a tertiary amine or a compound like CH3C(NO2)2).
- Since there are no alpha hydrogens, it will not react with nitrous acid.
- **Product**: No reaction.

### Step 5: Analyze Compound D
- This compound has a structure that allows for the presence of alpha hydrogen.
- The alpha hydrogen will be replaced by the nitroso group when treated with nitrous acid.
- **Product**: CH3-C(=O)-C(CH3)-O2 (and possibly tautomerization).

### Conclusion
Based on the analysis, the compound that does not react with nitrous acid is **Compound C**, as it lacks alpha hydrogens.

### Final Answer
**C** (the compound without alpha hydrogen) does not react with nitrous acid.

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