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

Options

A.
B.
C.
D.

Answer

To determine which nitro-compound does not react with nitrous acid, we can follow these steps:

### Step 1: Understand the Reaction of Nitro-Compounds with Nitrous Acid
Nitrous acid (HNO2) reacts differently with various types of amines. It is important to know the types of nitro-compounds we are dealing with. Generally, primary (1°) and secondary (2°) nitro-compounds will react with nitrous acid, while tertiary (3°) nitro-compounds do not.

### Step 2: Identify the Types of Nitro-Compounds
We need to classify the nitro-compounds in the options provided (not specified in the question but typically include primary, secondary, and tertiary nitro-compounds).

- **Primary Nitro-Compounds (1°)**: These will react with nitrous acid to form nitrous acid derivatives.
- **Secondary Nitro-Compounds (2°)**: These will also react with nitrous acid but may yield different products.
- **Tertiary Nitro-Compounds (3°)**: These do not react with nitrous acid.

### Step 3: Analyze the Reaction Products
- **Primary Nitro-Compounds**: React to form nitrolic acid.
- **Secondary Nitro-Compounds**: React to form a product known as CO2 nitrole.
- **Tertiary Nitro-Compounds**: Do not react at all with nitrous acid.

### Step 4: Conclusion
From our analysis, we conclude that the tertiary nitro-compound is the one that does not react with nitrous acid.

### Answer
The nitro-compound that does not react with nitrous acid is the **tertiary nitro-compound**.

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