`R-COOHtoR-CH_(2)OH`. This mode of reduction of an
acid to alcohol can be effected by :

Options

A. `Zn//HCl`
B. Na-alcohol
C. Aluminium isopropoxide and isopropyl alcohol
D. `LiAlH_(4)`

Explanation

To convert a carboxylic acid (R-COOH) to a primary alcohol (R-CH2OH), we can use specific reducing agents. Here’s a step-by-step solution:

### Step 1: Identify the Reactants and Products
- **Reactant**: R-COOH (Carboxylic acid)
- **Product**: R-CH2OH (Primary alcohol)

### Step 2: Determine the Type of Reaction
- This is a reduction reaction where the carboxylic acid is being reduced to a primary alcohol.

### Step 3: Select the Appropriate Reducing Agent
- The most suitable reducing agents for this conversion are:
- **Lithium Aluminium Hydride (LiAlH4)**: This is a strong reducing agent capable of reducing carboxylic acids to alcohols.
- **Diborane (B2H6)**: This is another reducing agent that can also achieve the same conversion.

### Step 4: Write the Reaction
- The reduction can be represented as follows:
\[ \text{R-COOH} + \text{LiAlH}_4 \rightarrow \text{R-CH}_2\text{OH} \]
or
\[ \text{R-COOH} + \text{B}_2\text{H}_6 \rightarrow \text{R-CH}_2\text{OH} \]

### Step 5: Conditions for the Reaction
- The reaction typically requires the presence of an ether solvent to stabilize the reducing agent during the reaction process.
- After the reduction, an acid work-up (like H3O+) is often used to protonate the alkoxide intermediate formed during the reduction.

### Final Answer
The mode of reduction of an acid (R-COOH) to an alcohol (R-CH2OH) can be effectively achieved using **Lithium Aluminium Hydride (LiAlH4)** or **Diborane (B2H6)**.

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