Question

Which among the following is haloalkyne?

• A. Chloroethyne
• B. 3 - Chloropropyne
• C. 1 - Chloropent - 2 - yne
• D. 4 - Chloropent - 2 - yne

Hint:

A haloalkyne has the halogen directly on a triple-bonded carbon.

Answer 1

The Correct Option is A

Step 1: Draw the structures
(A) $\text{Cl-C}\equiv\text{CH}$. (B) $\text{HC}\equiv\text{C-CH}_2\text{Cl}$. (C) pent-2-yne with Cl on C-1, an sp$^3$ carbon. (D) pent-2-yne with Cl on C-4, an sp$^3$ carbon.

Step 2: Check where the halogen sits
Only in (A) is the halogen bonded to a carbon of the triple bond, which is the defining feature of a haloalkyne. So (A).

Final Answer:
Only chloroethyne has the halogen on the triple-bonded carbon, option (A). \[ \boxed{\text{Chloroethyne}} \]