Primary alcohols can be obtained can be obtained from the reaction of the RMgX with

Options

A. `CO_(2)`
B. HCHO
C. `CH_(3) CHO`
D. `H_(2) O`

Answer

To obtain primary alcohols from the reaction of RMgX (Grignard reagent), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Grignard Reagent**:
The Grignard reagent is represented as RMgX, where R is an alkyl or aryl group, Mg is magnesium, and X is a halogen (like Cl, Br, or I).

2. **Understand the Reaction with Carbonyl Compounds**:
Grignard reagents react with carbonyl compounds through nucleophilic addition. The carbonyl group (C=O) is polarized, making the carbon atom electrophilic and susceptible to attack by the nucleophilic R group from the Grignard reagent.

3. **Select the Appropriate Carbonyl Compound**:
To obtain a primary alcohol, we need to react RMgX with an aldehyde. Specifically, we want to use formaldehyde (HCHO), which is the simplest aldehyde and has only one carbon.

4. **Nucleophilic Attack**:
When RMgX reacts with formaldehyde, the R group (from RMgX) acts as a nucleophile and attacks the electrophilic carbon of the carbonyl group (C=O). This results in the formation of a tetrahedral intermediate.

5. **Protonation**:
After the nucleophilic addition, the intermediate is treated with water (or an acid) to protonate the alkoxide ion (the negatively charged oxygen), leading to the formation of the primary alcohol.

6. **Final Product**:
The final product of this reaction is a primary alcohol, specifically RCH2OH, where R is the alkyl group from the Grignard reagent.

### Conclusion:
The primary alcohols can be obtained from the reaction of RMgX with formaldehyde (HCHO).