Which of the following reaction does not form an ether ?

Options

A. `C_6H_6OH+RBroverset("aq.NaOH)rarr`
B. `CH_3-underset(CH_3)underset(|)overset(CH_3)overset(|)C-CH=CH_2+ROH+Hg("OOCCF"_3)_2overset(NaBF_4)rarr`
C. `(CH_3)_3"CCl"+C_2H_5O^(-)Na^(+)rarr`
D. `CH_3CH_2OHunderset(413K)overset(H_2SO_4)rarr`

Answer

To determine which of the following reactions does not form an ether, let's analyze each reaction step by step.

### Step 1: Analyzing Reaction 1
**Reaction:** Phenol + RBr + Aqueous NaOH

- Phenol (C6H5OH) reacts with RBr in the presence of aqueous NaOH.
- Aqueous NaOH deprotonates phenol, forming phenoxide ion (C6H5O⁻).
- The phenoxide ion acts as a nucleophile and attacks the alkyl halide (RBr).
- The bromine (Br) leaves as a leaving group, resulting in the formation of an ether (C6H5-O-R).

**Conclusion:** This reaction forms an ether.

### Step 2: Analyzing Reaction 2
**Reaction:** CH3C(CH3)2 + CH2=CH2 + ROH + AgCOOCF3 + NaBF4

- The double bond in CH2=CH2 forms a complex with Hg²⁺ (from AgCOOCF3).
- The alcohol (ROH) acts as a nucleophile and attacks the carbon of the double bond.
- After the reaction, an ether is formed due to the substitution of the double bond.

**Conclusion:** This reaction also forms an ether.

### Step 3: Analyzing Reaction 3
**Reaction:** (CH3)3CCl + C2H5O⁻ (Sodium ethoxide)

- The tertiary alkyl halide (CCl) is sterically hindered.
- Sodium ethoxide can act as a base and abstracts a hydrogen atom rather than acting as a nucleophile.
- This leads to the formation of a double bond (alkene) instead of an ether.

**Conclusion:** This reaction does NOT form an ether.

### Step 4: Analyzing Reaction 4
**Reaction:** Ethanol + Concentrated H2SO4 + Heat

- When two molecules of ethanol react in the presence of concentrated sulfuric acid and heat, water is eliminated.
- The resulting product is an ether (CH3CH2OCH2CH3).

**Conclusion:** This reaction forms an ether.

### Final Answer
The only reaction that does not form an ether is **Reaction 3**.

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