What is the IUPAC name of the following substance?

3,3—Dimethyl—1—butyne

OR

3,3—Dimethylbut—1—yne

Explanation:

The structure of the compound can also be in this form:

HC≡C—C(CH3)2—CH3

So to name the compound we:

1. Locate the longest continuous carbon chain i.e butene

2. Identify the substituents attached to the chain i.e two CH3 group

3. Since the functional group here is the triple bond, we start counting from the side that gives the triple bond the lowest low count i.e from the left side. We must also indicate the position of the triple bond in the name.

4. Now we combine all from the above to get the name.

So, the name of the compound is 3,3—Dimethyl—1—butyne. This can also be written as 3,3—Dimethylbut—1—yne

Any of the two is correct.