IUPAC Name of `C_(6)H_(5)COC_(2)H_(5)`

Options

A. Ethyl phenyl methanone
B. 1-Phenyl propan-1-one
C. 3-Phenyl propanone
D. None of these

Answer

To determine the IUPAC name of the compound with the molecular formula \( C_6H_5COC_2H_5 \), we can follow these steps:

### Step 1: Identify the structure of the compound
The molecular formula \( C_6H_5COC_2H_5 \) can be broken down into two parts:
- \( C_6H_5 \) corresponds to a phenyl group (a benzene ring minus one hydrogen).
- \( C_2H_5 \) corresponds to an ethyl group.

The structure can be represented as:
- A phenyl group (C6H5) attached to a carbonyl group (C=O), which is then connected to an ethyl group (C2H5).

### Step 2: Determine the functional groups
In this compound, the key functional group is the carbonyl group (C=O), which indicates that this compound is a ketone. The phenyl group is a substituent on the aliphatic chain.

### Step 3: Number the carbon chain
When naming the compound, we need to start numbering from the carbonyl group because it has the highest priority as a functional group. The carbonyl carbon is considered carbon 1. The ethyl group will be on carbon 2.

- Carbon 1: Carbonyl carbon (C=O)
- Carbon 2: Ethyl group (C2H5)
- Carbon 3: Connected to the phenyl group (C6H5)

### Step 4: Write the IUPAC name
Now that we have identified the structure and numbered the carbon chain, we can write the IUPAC name. The compound consists of:
- A phenyl group at position 1.
- A three-carbon chain (propane) with a carbonyl group at position 1.

Thus, the IUPAC name can be written as:
- **1-Phenylpropane-1-one**

### Final Answer:
The IUPAC name of \( C_6H_5COC_2H_5 \) is **1-Phenylpropane-1-one**.

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