1 - Methylcyclohexene on addition of HCl produces

Options

A. 1 - chloro -1- methylcyclohexane
B. `(pm)`-trans -2- chloro -1- methylcyclohexane
C. `(pm)` cis -2- chloro -1- methylcyclohexane
D. 1 - chloro -2- methylcyclohexane

Answer

To solve the problem of the reaction of 1-Methylcyclohexene with HCl, we can follow these steps:

### Step 1: Identify the Structure of 1-Methylcyclohexene
1-Methylcyclohexene is a cyclohexene ring with a methyl group attached to the first carbon. The double bond in the cyclohexene makes it an alkene.

### Step 2: Understand the Reaction with HCl
When 1-Methylcyclohexene reacts with HCl, the double bond acts as a nucleophile and will attack the hydrogen ion (H⁺) from HCl. This leads to the formation of a carbocation.

### Step 3: Determine the Possible Carbocations
There are two possible sites for the formation of the carbocation:
- **Carbocation A**: Formed when H⁺ adds to the carbon atom of the double bond that is attached to the methyl group (C1).
- **Carbocation B**: Formed when H⁺ adds to the carbon atom of the double bond that is not attached to the methyl group (C2).

### Step 4: Analyze the Stability of the Carbocations
- **Carbocation A**: This carbocation has a methyl group (CH₃) attached to it, making it a secondary carbocation. It has 3 alpha hydrogens from the neighboring carbons.
- **Carbocation B**: This carbocation has no alkyl groups attached, making it a primary carbocation. It has only 1 alpha hydrogen.

Since carbocation A is more stable due to the presence of the methyl group, it will be the favored product.

### Step 5: Final Product Formation
Once the more stable carbocation (Carbocation A) is formed, the chloride ion (Cl⁻) from HCl will attack this carbocation, leading to the formation of the final product.

### Step 6: Write the Final Product
The final product of the reaction between 1-Methylcyclohexene and HCl is 1-Chloro-1-methylcyclohexane.

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