Question

Following are structural formulas and common names for four molecules that contain both a carbon-carbon double bond and another functional group. Give each an IUPAC name.

Short answer

Answer: The IUPAC name of CH3CH2CH(CH3)CHO is 3-Methylbutanal.

Step-by-step solution

Identify the longest carbon chain containing the highest priority functional group

In this molecule, the longest carbon chain has 4 carbon atoms: CH3CH2CH(CH3)CHO. The functional group present in this molecule is an aldehyde (CHO) which has higher priority over the carbon-carbon double bond.

Number the carbon atoms

We will number the carbon atoms in the chain starting from the end at which the aldehyde group is present, assigning it the lowest possible number. The numbering of the carbon atoms will be: 1 -CHO 2 3 4 -CH3

Name the substituents and their positions on the carbon chain

There is a methyl (CH3) group attached to the third carbon atom in the chain. Therefore, it is called 3-methyl.

Assemble the IUPAC name for the molecule

Now, we can assemble the IUPAC name for the molecule, using the substituents' names and the positions. The name will be: 3-Methylbutanal