`C_2H_5CNoverset(HNO_(2))toAoverset(PCl_(5))toBoverset(NH_(3))toC` end product in the given sequence is

Options

A. `C_2H_5CN`
B. `CH_3NH_2`
C. `C_2H_5NH_2`
D. `CH_3CONH_2`

Answer

To solve the problem step by step, we will analyze each reaction in the sequence provided:

### Step 1: Reaction of Ethyl Cyanide with Nitrous Acid

**Reaction:**
Ethyl cyanide (C₂H₅C≡N) reacts with nitrous acid (HNO₂) at low temperatures (0 to 5 degrees Celsius).

**Product:**
This reaction leads to the formation of an unstable diazonium compound (A). The diazonium compound is not stable and will undergo hydrolysis.

### Step 2: Hydrolysis of the Diazonium Compound

**Hydrolysis:**
The unstable diazonium compound (A) is hydrolyzed in the presence of water.

**Product:**
The hydrolysis of the diazonium compound yields a carboxylic acid, specifically ethanoic acid (acetate) or ethyl carbamate (C₂H₅COOH). However, in this context, we will focus on the formation of ethyl chloride (C₂H₅Cl) as we proceed to the next step.

### Step 3: Reaction of Ethyl Chloride with PCl₅

**Reaction:**
The ethyl chloride (C₂H₅Cl) is then treated with phosphorus pentachloride (PCl₅).

**Product:**
This reaction will convert the ethyl chloride into a more reactive intermediate, which is typically an alkyl chloride. However, in this case, it is important to note that PCl₅ can also facilitate the conversion of the alcohol or amine derivatives.

### Step 4: Reaction of the Intermediate with Ammonia

**Reaction:**
The product from the previous step (B) is then reacted with ammonia (NH₃).

**Product:**
This reaction leads to the formation of ethyl amine (C₂H₅NH₂) as the final product (C). During this reaction, hydrochloric acid (HCl) is released as a by-product.

### Final Product

After analyzing all the steps, the end product (C) in the given sequence is ethyl amine (C₂H₅NH₂).

### Summary of Steps:
1. Ethyl cyanide reacts with nitrous acid to form an unstable diazonium compound (A).
2. The diazonium compound undergoes hydrolysis to yield ethyl chloride (B).
3. Ethyl chloride reacts with PCl₅ to form a reactive intermediate.
4. The intermediate reacts with ammonia to produce ethyl amine (C).

### Final Answer:
The end product in the given sequence is **ethyl amine (C₂H₅NH₂)**.

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