Line-Bond formula of 6-ethyl-2-octyne

The Correct Answer and Explanation is:

Line-Bond Formula of 6-Ethyl-2-octyne

To draw the line-bond (skeletal) structure of 6-ethyl-2-octyne, follow these steps:

Step-by-Step Structure:

Parent Chain Identification:
The parent chain is octyne, which means it has 8 carbon atoms with a triple bond starting at carbon 2.
Numbering the Chain:
Number from the end closest to the triple bond, so the triple bond starts at carbon 2.
Substituent Placement:
A methyl group (-CH₂CH₃) is attached at carbon 6, making it 6-ethyl.
Line-Bond Drawing:
- Start drawing a zigzag line for the 8-carbon chain.
- Insert a triple bond between C2 and C3.
- On the 6th carbon, draw a line for the ethyl group extending outward.

Line-Bond Structure:

CH3–C≡C–CH2–CH(CH2CH3)–CH2–CH3
       |    
      C2≡C3

And as a skeletal (line-bond) diagram, it would look like this:

     CH2CH3
        |
CH3–C≡C–CH2–CH–CH2–CH3

(Note: This representation is simplified for text. A real skeletal structure would be a zigzag line with a triple bond between the second and third carbons and a branch at the sixth carbon.)

Explanation

6-Ethyl-2-octyne is an alkyne with a linear carbon chain of eight atoms and a triple bond starting at the second carbon. The name gives a clear breakdown:

“Octyne” indicates an 8-carbon chain and a triple bond.
“2-” shows the triple bond begins at the second carbon (closest to the chain end).
“6-ethyl” indicates an ethyl group (–CH₂CH₃) is attached to the sixth carbon in the chain.

To draw the line-bond structure, start with a zigzag backbone representing the carbon chain. Each bend or end of a line segment implies a carbon atom. The triple bond is drawn as three parallel lines between the second and third carbons, indicating a carbon-carbon triple bond.

The ethyl substituent is placed at the sixth carbon. It branches off from the main chain as a short line, representing the –CH₂CH₃ group. In line-bond structures, hydrogen atoms bonded to carbon are usually omitted for clarity, assuming each carbon follows the valency of 4.

This structural format helps organic chemists quickly interpret molecular geometry and reactivity. The presence of a triple bond adds linearity and affects the molecule’s physical and chemical behavior. For example, triple bonds are sites of high electron density, making them reactive in addition reactions.

In summary, 6-ethyl-2-octyne combines both unsaturation (alkyne) and branching (ethyl group), and its line-bond structure helps visualize this combination efficiently.