CH3−C|CH2−CH3=CH−CH2−CH2−CH3
3-Methyl-3-heptene
Let`s take a guess.
Do you think it is 2-Ethyl-2-hexene?
No, it is not
The correct answer is 3-methyl-3-heptene.
Why?
Because parent chain is
Word root →Hept
So, double bond at C3⇒3-heptane
Methyl at C3⇒ 3-Methyl-3-heptane