Cyclohexylamine when treated with nitrous acid yields (P). On treating (P) with PCC results in (Q). When (Q) is heated with dil. NaOH we get (R) The final product (R) is :

Options

A.
B.
C.
D.

Answer

To solve the given question step by step, we will analyze the reactions involving cyclohexylamine and the reagents mentioned.

### Step 1: Identify the structure of Cyclohexylamine
Cyclohexylamine is a six-membered carbon ring with an amine group (-NH2) attached to it. The structure can be represented as follows:

```
NH2
|
C1 - C2
/ \
C6 C3
\ /
C5 - C4
```

### Step 2: Treat Cyclohexylamine with Nitrous Acid (HNO2)
When cyclohexylamine is treated with nitrous acid (HNO2), it undergoes a diazotization reaction. The amine group (-NH2) is converted into a hydroxyl group (-OH), resulting in the formation of cyclohexanol (P).

**Reaction:**
Cyclohexylamine + HNO2 → Cyclohexanol (P)

### Step 3: Treat Cyclohexanol (P) with PCC
Pyridinium chlorochromate (PCC) is a mild oxidizing agent. When cyclohexanol (P) is treated with PCC, it gets oxidized to cyclohexanone (Q), which is a ketone.

**Reaction:**
Cyclohexanol (P) + PCC → Cyclohexanone (Q)

### Step 4: Heat Cyclohexanone (Q) with Dilute NaOH
When cyclohexanone (Q) is heated with dilute sodium hydroxide (NaOH), it can undergo an aldol condensation reaction. However, since we are dealing with a cyclic ketone, it will not undergo aldol condensation in the traditional sense. Instead, it can lead to the formation of a product through a rearrangement or elimination reaction.

In this case, heating cyclohexanone with dilute NaOH can lead to the formation of cyclohexene (R) through dehydration.

**Reaction:**
Cyclohexanone (Q) + Dilute NaOH (heat) → Cyclohexene (R)

### Final Product (R)
The final product (R) is cyclohexene, which is an alkene.

### Summary of Reactions:
1. Cyclohexylamine + HNO2 → Cyclohexanol (P)
2. Cyclohexanol (P) + PCC → Cyclohexanone (Q)
3. Cyclohexanone (Q) + Dilute NaOH (heat) → Cyclohexene (R)

### Final Answer:
The final product (R) is **cyclohexene**.

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