Grignard reagent is obtained when magnesium is treated with

Options

A. Alkyl halide in presence of alcohol
B. Alkyl halide in presence of phenol
C. Alkyl halide in presence of dry ether
D. Alkyl halide in presence of alcoholated ether

Answer

To solve the question regarding how Grignard reagents are obtained, we can break down the process step by step:

### Step-by-Step Solution:

1. **Understanding Grignard Reagents**: Grignard reagents are organomagnesium compounds that are formed when magnesium reacts with alkyl or aryl halides. They are represented as R-Mg-X, where R is an alkyl or aryl group, and X is a halogen (like Cl, Br, or I).

2. **Identifying the Reactants**: The key reactants in the formation of Grignard reagents are magnesium (Mg) and alkyl halides (RX). Alkyl halides can be primary, secondary, or tertiary halides.

3. **Role of Solvent**: The reaction requires a suitable solvent. Grignard reagents are typically prepared in the presence of dry ether. Dry ether is essential because the presence of moisture (water) can lead to the hydrolysis of the Grignard reagent, rendering it ineffective.

4. **The Reaction**: The general reaction can be represented as:
\[ \text{R-X} + \text{Mg} \xrightarrow{\text{dry ether}} \text{R-Mg-X} \]
Here, R-X is the alkyl halide, and R-Mg-X is the Grignard reagent formed.

5. **Conclusion**: Therefore, the correct answer to the question is that Grignard reagents are obtained when magnesium is treated with alkyl halide in the presence of dry ether.

### Final Answer:
Grignard reagent is obtained when magnesium is treated with **alkyl halide in the presence of dry ether**.