Which of the following is an example of conjugated diketone ?

Options

A. `CH_3overset(O)overset(||)C-CH_2-CH_2-CH_2-overset(O)overset(||)(C)-CH_3`
B.
C.
D.

Answer

To determine which of the following is an example of a conjugated diketone, let's first understand what a conjugated diketone is.

### Step 1: Define Conjugated Diketone
A conjugated diketone is a compound that contains two carbonyl groups (C=O) that are separated by a double bond (C=C). The general structure can be represented as R1C(=O)-C=C-R2C(=O), where R1 and R2 can be hydrogen or hydrocarbon groups.

### Step 2: Identify Examples
Now, let's look at some common examples of diketones:
1. **2,3-Butanedione (Diacetyl)**: This compound has the structure CH3C(=O)C(=O)CH3. The two carbonyl groups are adjacent to a double bond, making it a conjugated diketone.
2. **1,3-Butanedione**: This compound has the structure CH3C(=O)CH2C(=O)CH3. The carbonyl groups are separated by a single bond, so it is not conjugated.
3. **Cyclopentane-1,3-dione**: This compound has two carbonyl groups that are separated by a single bond in a cyclic structure, so it is not conjugated.

### Step 3: Conclusion
From the examples, **2,3-Butanedione (Diacetyl)** is a conjugated diketone because it has the required structure of two carbonyl groups separated by a double bond.

### Final Answer
The example of a conjugated diketone is **2,3-Butanedione (Diacetyl)**.

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