Identify structure of trans-2-hexenal.

Options

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Answer

To identify the structure of trans-2-hexenal, we can follow these steps:

### Step 1: Understand the Name
The compound is named "trans-2-hexenal." The prefix "hex" indicates that the main chain has six carbon atoms. The "enal" suffix indicates that it is an aldehyde with a double bond (alkenal), and the "trans" indicates the geometric isomerism of the double bond.

**Hint:** Break down the name into parts to understand the structure: "hex" for six carbons, "enal" for an aldehyde with a double bond, and "trans" for the geometric configuration.

### Step 2: Draw the Carbon Chain
Start by drawing a straight chain of six carbon atoms (C1 to C6). This will be the backbone of our molecule.

**Hint:** Remember that "hex" means six; draw six carbon atoms in a row.

### Step 3: Identify the Double Bond
The "2" in "trans-2-hexenal" indicates that the double bond is located between the second and third carbon atoms (C2=C3).

**Hint:** The number before the name indicates the position of the double bond in the carbon chain.

### Step 4: Add the Aldehyde Group
Since it is an aldehyde (as indicated by "enal"), we need to add a carbonyl group (C=O) at the end of the carbon chain. This will be on C1, making it an aldehyde.

**Hint:** Aldehydes have the functional group -CHO at the end of the carbon chain.

### Step 5: Determine the Geometric Configuration
For the "trans" configuration, the substituents on the double bond must be on opposite sides. On C2 and C3, we will have:
- On C2: a hydrogen (H) and a CH3 group (from C1).
- On C3: a hydrogen (H) and a CHO group (from C1).

**Hint:** Visualize the double bond; for trans, the larger groups (in this case, CHO and CH3) should be on opposite sides.

### Step 6: Complete the Structure
Now, let's complete the structure:
- C1: CHO (aldehyde)
- C2: H and CH3
- C3: H and CH
- C4: CH2
- C5: CH2
- C6: CH3

The complete structure can be represented as:
```
CH3
|
CHO-C=C-CH2-CH2-CH3
```
Where the double bond is between C2 and C3, and the aldehyde group is at C1.

**Hint:** Make sure to check that the groups on the double bond are correctly positioned for the trans configuration.

### Final Structure
The final structure of trans-2-hexenal is:
```
CH3
|
CHO-C=C-CH2-CH2-CH3
```