Compounds (A) and (C ) in the following reactions are
`CH_(3)CHO overset((i)CH_(3)MgBr)underset((ii)H_(2)O)to(A) overset(H_(2)SO_(4),Delta)to(B)overset("Hydroboration oxidation")to (C)`

Options

A. identical
B. positional isomers
C. functional isomers
D. optical isomers.

Explanation

To solve the problem step-by-step, we will analyze the reactions involving compound (A) and compound (C) based on the provided information.

### Step 1: Identify Compound A
1. **Starting Compound**: The reaction starts with acetaldehyde (CH₃CHO).
2. **Reaction with Grignard Reagent**: When acetaldehyde reacts with the Grignard reagent (CH₃MgBr), the nucleophile (CH₃⁻) attacks the electrophilic carbon of the carbonyl group (C=O) in acetaldehyde.
3. **Formation of Alcohol**: This results in the formation of a magnesium alkoxide intermediate. Upon hydrolysis (reaction with water), this intermediate converts to a secondary alcohol.
- **Resulting Compound A**: The product is 2-butanol (CH₃CH(OH)CH₂CH₃).

### Step 2: Identify Compound B
1. **Dehydration of Compound A**: The secondary alcohol (2-butanol) is then treated with sulfuric acid (H₂SO₄) and heated. This leads to dehydration, where water is removed.
2. **Formation of Alkene**: The dehydration of 2-butanol results in the formation of butene (specifically, 2-butene).
- **Resulting Compound B**: The product is 2-butene (CH₃CH=CHCH₃).

### Step 3: Identify Compound C
1. **Hydroboration-Oxidation of Compound B**: The next step involves hydroboration-oxidation of 2-butene.
- **Hydroboration**: In this step, 2-butene reacts with diborane (B₂H₆) in tetrahydrofuran (THF), leading to the formation of trialkyl borane.
- **Oxidation**: This is followed by oxidation with hydrogen peroxide (H₂O₂) in a basic medium, resulting in the addition of -OH across the double bond.
2. **Anti-Markovnikov Addition**: According to the anti-Markovnikov rule, the hydroxyl group (-OH) will add to the less substituted carbon, leading to the formation of a primary alcohol.
- **Resulting Compound C**: The product is butanol (specifically, 1-butanol, CH₃CH₂CH₂OH).

### Summary of Compounds
- **Compound A**: 2-butanol (CH₃CH(OH)CH₂CH₃)
- **Compound C**: 1-butanol (CH₃CH₂CH₂OH)

### Final Answer
- Compound (A) is 2-butanol.
- Compound (C) is 1-butanol.

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