Phenol reacts with `CHCI_(3)` and `NaOH` (at 340K) to give .

Options

A. o-chlorophenol
B. salicyladehyde
C. benzaldehyde
D. chlorobenzene

Explanation

To solve the problem of the reaction between phenol and chloroform in the presence of sodium hydroxide at 340 K, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactants in this reaction are phenol (C6H5OH) and chloroform (CHCl3). Sodium hydroxide (NaOH) acts as a base in this reaction.

2. **Understand the Reaction Type**:
- This reaction is known as the Reimer-Tiemann reaction. It involves the ortho-formylation of phenols using chloroform and a strong base.

3. **Write the Reaction Equation**:
- The reaction can be represented as follows:
\[ \text{C}_6\text{H}_5\text{OH} + \text{CHCl}_3 + \text{NaOH} \rightarrow \text{C}_6\text{H}_4(\text{OH})(\text{CHO}) + 3 \text{NaCl} + 2 \text{H}_2\text{O} \]
- Here, C6H4(OH)(CHO) represents salicylaldehyde (ortho-hydroxybenzaldehyde).

4. **Product Formation**:
- The main product formed from this reaction is salicylaldehyde (C6H4(OH)(CHO)). This compound has both a hydroxyl group (–OH) and an aldehyde group (–CHO) attached to the aromatic ring.

5. **By-products**:
- The by-products of this reaction include sodium chloride (NaCl) and water (H2O).

6. **Final Answer**:
- Therefore, the final product of the reaction between phenol and chloroform in the presence of sodium hydroxide at 340 K is salicylaldehyde.

### Summary of the Reaction:
- **Reactants**: Phenol (C6H5OH), Chloroform (CHCl3), Sodium Hydroxide (NaOH)
- **Product**: Salicylaldehyde (C6H4(OH)(CHO))
- **By-products**: Sodium Chloride (NaCl), Water (H2O)