When tertiary butyl alcohol is passed over reduced copper, the reaction taking placed is

Options

A. primary alcohol
B. secondary alcohol
C. tertiary alcohol
D. dihydric alcohol

Explanation

To solve the question, we need to understand the reaction that occurs when tertiary butyl alcohol is passed over reduced copper. Here’s a step-by-step breakdown of the process:

### Step 1: Identify the Reactant
The reactant in this case is tertiary butyl alcohol, which has the structure:
\[ \text{(CH}_3)_3\text{C-OH} \]
This means it has three methyl groups (CH₃) attached to a central carbon atom that is also bonded to a hydroxyl group (OH).

### Step 2: Understand the Role of Reduced Copper
Reduced copper acts as a dehydrating agent when heated with alcohols. This means it can facilitate the removal of a water molecule (H₂O) from the alcohol.

### Step 3: Analyze the Structure of Tertiary Butyl Alcohol
Tertiary butyl alcohol does not have any alpha hydrogen atoms (hydrogens on the carbon adjacent to the carbon bearing the hydroxyl group). This is important because the absence of alpha hydrogens influences the type of reaction that occurs.

### Step 4: Reaction Mechanism
When tertiary butyl alcohol is heated in the presence of reduced copper:
1. The hydroxyl (OH) group is removed.
2. A hydrogen atom is removed from one of the methyl groups (CH₃) to form water (H₂O).
3. A double bond forms between the central carbon atom and the adjacent carbon atom.

### Step 5: Product Formation
The product of this reaction is an alkene, specifically isobutylene (or 2-methylpropene), which has the structure:
\[ \text{CH}_2=C(CH_3)_2 \]
This shows that the reaction results in the formation of a double bond.

### Step 6: Conclusion
The overall reaction can be summarized as:
\[ \text{(CH}_3)_3\text{C-OH} \xrightarrow{\text{Cu, heat}} \text{CH}_2=C(CH_3)_2 + \text{H}_2\text{O} \]
This process is known as a dehydration reaction because water is removed.

### Final Answer
When tertiary butyl alcohol is passed over reduced copper, the reaction taking place is a dehydration reaction that converts tertiary butyl alcohol into isobutylene (2-methylpropene) and water.