3-Phenyl-prop-2-enoic acid is IUPAC name of

Options

A. Mendallic acid
B. Pivallic acid
C. Succinic acid
D. Cinnamic acid.

Explanation

To determine the common name of 3-Phenyl-prop-2-enoic acid, we will follow these steps:

### Step 1: Understand the IUPAC Name
The IUPAC name "3-Phenyl-prop-2-enoic acid" indicates that we have:
- A propene backbone (3 carbon atoms) with a double bond.
- A phenyl group (C6H5) attached to the third carbon.
- A carboxylic acid functional group (-COOH) indicating it's an acid.

### Step 2: Draw the Structure
1. Start with the propene backbone:
- The carbon chain is: C1=C2-C3 (where C1 and C2 are involved in the double bond).
2. Add the phenyl group at the 3rd carbon (C3).
3. Add the carboxylic acid group (-COOH) at C1.

The structure can be represented as:
```
C6H5
|
H2C=C-COOH
```

### Step 3: Identify the Common Name
Now that we have the structure, we can identify the common name. The structure we have drawn corresponds to:
- C6H5-CH=CH-COOH, which is known as "Cinnamic acid."

### Conclusion
The common name for 3-Phenyl-prop-2-enoic acid is **Cinnamic acid**.

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