The reaction of formaldehyde with methyl magnesium bromide followed by hydrolysis gives

Options

A. secondary alcohol
B. primary alcohol
C. ketone
D. tertiary alcohol

Explanation

To solve the problem of what is produced when formaldehyde reacts with methyl magnesium bromide followed by hydrolysis, we can break down the steps as follows:

### Step 1: Understand the Reactants
- **Formaldehyde (HCHO)** is the simplest aldehyde, consisting of one carbon atom, one oxygen atom, and two hydrogen atoms.
- **Methyl magnesium bromide (CH3MgBr)** is a Grignard reagent, where the methyl group (CH3) acts as a nucleophile.

### Step 2: Reaction of Formaldehyde with Methyl Magnesium Bromide
- In this reaction, the nucleophilic carbon of the methyl group (from CH3MgBr) attacks the electrophilic carbon of the carbonyl group (C=O) in formaldehyde.
- This leads to the formation of a tetrahedral intermediate where the carbonyl oxygen becomes negatively charged.

### Step 3: Formation of Alkoxide Intermediate
- The reaction can be represented as:
\[ HCHO + CH3MgBr \rightarrow [H2C(OMgBr)CH3]^- \]
- Here, the carbonyl oxygen (O) becomes negatively charged and is now bonded to the magnesium bromide.

### Step 4: Hydrolysis of the Alkoxide
- Upon hydrolysis (addition of water), the alkoxide intermediate reacts with water:
\[ [H2C(OMgBr)CH3]^- + H2O \rightarrow H2C(OH)CH3 + Mg(OH)Br \]
- This results in the formation of an alcohol and magnesium hydroxide bromide.

### Step 5: Identify the Product
- The product formed is **2-methyl-1-propanol** (or simply methyl alcohol), which is a primary alcohol because the carbon atom bearing the hydroxyl group (OH) is attached to only one other carbon atom.

### Conclusion
Thus, the final product of the reaction of formaldehyde with methyl magnesium bromide followed by hydrolysis is **a primary alcohol**.