Cyclohexanol can be converted into cyclohexylamine by following two routes. Which of the following methods is expected to give good yield of cyclohexylamine ?

Options

A.
B.
C. both are equally suitable
D. neither of the two

Answer

To determine which method is expected to give a good yield of cyclohexylamine from cyclohexanol, we can analyze the two proposed routes step by step.

### Step-by-Step Solution:

1. **Identify the Starting Material**:
- The starting material is cyclohexanol (C6H11OH).

2. **Route 1: Oxidation followed by Reduction**:
- In the first method, cyclohexanol is oxidized using potassium dichromate (K2Cr2O7), a strong oxidizing agent. This oxidation converts cyclohexanol to cyclohexanone (C6H10O).
- The reaction can be represented as:
\[ \text{C6H11OH} \xrightarrow{\text{K2Cr2O7}} \text{C6H10O} \]
- Following this, cyclohexanone is treated with ammonia (NH3) in the presence of nickel (Ni) to produce cyclohexylamine (C6H11NH2).
- The reaction can be represented as:
\[ \text{C6H10O} + \text{NH3} \xrightarrow{\text{Ni}} \text{C6H11NH2} \]
- However, this process involves multiple steps and the reagents used (K2Cr2O7 and Ni) are toxic, which can complicate the reaction and reduce the overall yield.

3. **Route 2: Halogenation followed by Amine Formation**:
- In the second method, cyclohexanol is first converted to cyclohexyl bromide (C6H11Br) using phosphorus tribromide (PBr3).
- The reaction can be represented as:
\[ \text{C6H11OH} \xrightarrow{\text{PBr3}} \text{C6H11Br} \]
- Then, cyclohexyl bromide is treated with ammonia (NH3) to produce cyclohexylamine.
- The reaction can be represented as:
\[ \text{C6H11Br} + \text{NH3} \rightarrow \text{C6H11NH2} + \text{HBr} \]
- This method is more straightforward, involves fewer steps, and uses non-toxic reagents.

4. **Comparison of Yields**:
- The first route involves toxic reagents and multiple steps, which can lead to lower yields and complicate the process.
- The second route is simpler, involves fewer reagents, and is expected to give a better yield of cyclohexylamine due to the direct conversion from cyclohexyl bromide to cyclohexylamine.

5. **Conclusion**:
- Based on the analysis, **Route 2** (halogenation followed by amine formation) is expected to give a better yield of cyclohexylamine.

### Final Answer:
**Route 2 is expected to give a good yield of cyclohexylamine.**