Name the compounds below.
(the CH3 is above the CCH2, the O is above the C, and for the second its O above the C)
CH3 O O
l ll ll
There are specific rules set out by the IUPAC (International Union of Pure and Applied Chemistry) for the naming of organic molecules. You always start by identifying the longest carbon chain in the molecule and number it so that the first substituent has the lowest number. For the first compound, the carbon chain is six carbons long and it has a carboxylic acid on one end. So we number the chain with the acid on the first carbon. That would put the methyl group on the fourth carbon. So the name would be 4-methylhexanoic acid.
For the second compound, we can see that it is an ester. The longest unbroken carbon chain is seven carbons long. We number so that the ester is on carbon number one. The other end of the ester has three carbons on it. We can name this one of two ways. It could be called either n-propyl 1-heptanoate or 1-heptanoic acid n-propyl ester.