Write the IUPAC name of
` CH_3- underset(NH_2) underset(|) (CH_2) -CHO`

Options

A. 1-Aminopropanaldehyde
B. 2-Aminopropanal
C. 1-Aminoethan-1-al
D. None of the above

Explanation

To write the IUPAC name of the compound `CH3-CH(NH2)-CH2-CHO`, we will follow these steps:

### Step 1: Identify the longest carbon chain
The structure provided has three carbon atoms in the longest chain, which is `CH3-CH-CH2-CHO`.

### Step 2: Identify the functional groups
In the structure, we have two functional groups:
1. An aldehyde group (`-CHO`)
2. An amine group (`-NH2`)

### Step 3: Determine the principal functional group
According to IUPAC nomenclature rules, the aldehyde group has a higher priority than the amine group. Therefore, the aldehyde will be considered the principal functional group.

### Step 4: Number the carbon chain
We will number the carbon chain starting from the end closest to the aldehyde group:
- The carbon with the aldehyde group is carbon 1.
- The next carbon (attached to the amine) is carbon 2.
- The last carbon is carbon 3.

So, the numbering is as follows:
1. `CHO` (carbon 1)
2. `CH(NH2)` (carbon 2)
3. `CH3` (carbon 3)

### Step 5: Name the substituents
The amine group (`NH2`) is located on carbon 2. We will denote it as "2-amino".

### Step 6: Combine the names
Now we can combine the names:
- The longest chain is a three-carbon chain with an aldehyde, which is called "propanal".
- The amine substituent is "2-amino".

Putting it all together, the IUPAC name of the compound is **2-amino-propanal**.

### Final Answer:
**2-amino-propanal**

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