The reaction of RCN with R'MgX, followed by hydrolysis gives

Options

A. an aldehyde
B. a ketone
C. `2^@` alcohol
D. `3^@` alcohol

Answer

To solve the problem, we will analyze the reaction of RCN (a nitrile) with R'MgX (a Grignard reagent) followed by hydrolysis step by step.

### Step 1: Identify the Reactants
The reactants are:
- RCN, which is a nitrile (RC≡N).
- R'MgX, which is a Grignard reagent.

### Step 2: Understand the Mechanism of Reaction
In the reaction, the Grignard reagent (R'MgX) will react with the nitrile (RCN). The carbon atom in the nitrile is electrophilic, while the alkyl group (R') from the Grignard reagent is nucleophilic.

### Step 3: Nucleophilic Attack
The nucleophilic alkyl group (R') from R'MgX attacks the electrophilic carbon of the nitrile (RC≡N). This leads to the formation of an intermediate:
- The carbon of the nitrile becomes a double bond with the alkyl group (R') and the nitrogen becomes bonded to the magnesium halide (MgX).

The reaction can be represented as:
\[ RCN + R'MgX \rightarrow RCR' = N \cdots MgX \]

### Step 4: Hydrolysis of the Intermediate
Upon hydrolysis (usually with water or an acid), the intermediate undergoes a reaction where the nitrogen atom is protonated, and the bond between the carbon and nitrogen breaks. This results in the formation of a ketone and a byproduct.

The hydrolysis can be represented as:
\[ RCR' = N \cdots MgX + H_2O \rightarrow RC(=O)R' + Mg(OH)X + NH_2 \]

### Step 5: Identify the Product
The final product after hydrolysis is a ketone (RC(=O)R') along with byproducts (Mg(OH)X and NH2).

### Final Answer
The reaction of RCN with R'MgX followed by hydrolysis gives a ketone.

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