Teritary alcohols can be prepared using R mg X with :

Options

A. Formaldehyde
B. Acetaldehyde
C. Acetone
D. Acetic acid

Answer

To prepare tertiary alcohols using Grignard reagents (R-MgX), we need to consider the types of carbonyl compounds that can react with them. Here's a step-by-step solution:

### Step 1: Understand Grignard Reagents
Grignard reagents are organomagnesium compounds represented as R-MgX, where R is an organic group and X is a halogen. They are highly reactive and can add to carbonyl compounds.

### Step 2: Identify the Type of Carbonyl Compounds
Grignard reagents react differently with various carbonyl compounds:
- **Formaldehyde (RCHO)**: Reacts to form primary alcohols.
- **Aldehydes (R'CHO)**: React to form secondary alcohols.
- **Ketones (R'CO-R'')**: React to form tertiary alcohols.

### Step 3: Reaction with Formaldehyde
When a Grignard reagent reacts with formaldehyde, the product is a primary alcohol:
\[ R-MgX + HCHO \rightarrow R-CH_2OH \] (Primary alcohol)

### Step 4: Reaction with Aldehydes
When a Grignard reagent reacts with an aldehyde, the product is a secondary alcohol:
\[ R-MgX + R'CHO \rightarrow R-CH(R')OH \] (Secondary alcohol)

### Step 5: Reaction with Ketones
When a Grignard reagent reacts with a ketone, the product is a tertiary alcohol:
\[ R-MgX + R'CO-R'' \rightarrow R-C(R')R''OH \] (Tertiary alcohol)

### Step 6: Identify the Correct Option
To prepare a tertiary alcohol using a Grignard reagent, we need to choose a ketone as the carbonyl compound. Among the options provided, we need to identify which one is a ketone.

### Conclusion
The correct answer is the option that contains a ketone, as it will yield a tertiary alcohol when reacted with the Grignard reagent.