Propanal and pentan-3-one are the ozonolysis products of an alkene? What is the structural formula of the alkene?

Explanation

To determine the structural formula of the alkene that yields propanal and pentan-3-one as ozonolysis products, we can follow these steps:

### Step 1: Identify the Products
The products of ozonolysis given are:
- Propanal (an aldehyde)
- Pentan-3-one (a ketone)

### Step 2: Write the Structures of the Products
- **Propanal (C3H6O)**: The structure is CH3-CH2-CHO.
- **Pentan-3-one (C5H10O)**: The structure is CH3-CO-CH2-CH2-CH3.

### Step 3: Understand Ozonolysis
Ozonolysis of an alkene involves breaking the double bond and forming carbonyl compounds (aldehydes and ketones). The general reaction can be represented as:
\[ R_1R_2C=C(R_3R_4) \xrightarrow{O_3} R_1R_2C=O + R_3C=O + \text{other products} \]

### Step 4: Determine the Alkene Structure
To find the alkene that would yield these products upon ozonolysis, we need to consider how the double bond in the alkene would split to form propanal and pentan-3-one.

1. **Constructing the Ozonide**:
- The ozonide structure would have the carbonyl groups in the positions where the double bond was.
- The carbon skeleton must accommodate both products.

2. **Connecting the Products**:
- The carbonyl from propanal (C1) and the carbonyl from pentan-3-one (C3) suggest that the double bond must be between C2 and C3 of a 5-carbon chain.

### Step 5: Write the Alkene Structure
Based on the above deductions, the alkene that would yield propanal and pentan-3-one upon ozonolysis can be represented as:
\[ \text{CH}_3-\text{CH}=\text{C}(\text{CH}_2\text{CH}_3)-\text{CH}_2\text{CH}_3 \]
This can be simplified to:
\[ \text{CH}_3-\text{CH}=\text{C}(\text{CH}_2\text{CH}_3)-\text{CH}_3 \]
This indicates that the alkene is 3-pentene.

### Final Answer
The structural formula of the alkene is:
\[ \text{CH}_3-\text{CH}=\text{C}(\text{CH}_2\text{CH}_3)-\text{CH}_3 \]

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