Question

Name the following compound.

• A. 3-methyl-4-formyl-but-2-ene
• B. 2-methyl-but-3-en-1-al
• C. 2-methyl-but-2-en-1-al
• D. None of these

Answer 1

The correct option is C 2-methyl-but-2-en-1-al

Let us look at the longest chain with maximum functional groups first.

Since aldehyde has to get first priority, the double bond will be number 2

So, suffix here would be -al and we have an -en- at position 2 and a methyl at position 2

Word root is but

So, name would be 2-methyl-but-2-en-1-al