Ethylamine can be prepared by the action of bromine and caustic potash on

Options

A. Acetamide
B. Propionamide
C. Formamide
D. Methyl cyanide.

Explanation

To prepare ethylamine through the action of bromine and caustic potash (potassium hydroxide), we will utilize the Hoffmann Bromamide Degradation method. Here’s a step-by-step solution:

### Step 1: Identify the Reaction
The reaction involves bromine (Br2) and potassium hydroxide (KOH) acting on an amide to produce a primary amine. The general reaction can be summarized as:
\[ \text{Amide} + \text{Br}_2 + \text{KOH} \rightarrow \text{Primary Amine} + \text{By-products} \]

### Step 2: Determine the Amide to Use
To produce ethylamine (C2H5NH2), we need to start with an amide that has one more carbon atom than the desired amine. Ethylamine has 2 carbon atoms, so we will use propionamide (C2H5CONH2), which has 3 carbon atoms.

### Step 3: Write the Reaction Equation
The reaction of propionamide with bromine and potassium hydroxide can be represented as follows:
\[ \text{C2H5CONH2} + \text{Br}_2 + \text{KOH} \rightarrow \text{C2H5NH2} + \text{By-products} \]
Here, the carbonyl (C=O) group from the amide is eliminated, and the remaining part forms ethylamine.

### Step 4: Conclusion
Thus, the correct reactant for the preparation of ethylamine by the action of bromine and caustic potash is propionamide.

### Final Answer:
Ethylamine can be prepared by the action of bromine and caustic potash on **propionamide**.

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