Now when it comes to naming compounds with multiple functional groups, we're going to say that priorities must be considered. And we're going to say that the functional group with the highest priority is named as the parent chain, and all other functional groups will be named as substituents. When it comes to functional group priorities, this is the order that you need to keep in mind. So carboxylic acids reign supreme. They have the highest priority of all the functional groups, followed by aldehydes, then ketones, then alcohols, then amines, and then ethers. These are the functional groups that we've curated because they're the ones that are usually mixed together within a multifunctional group compound. Now the memory tool we can use here is that cool alligators keep all animals excited. So this will help us remember cool for carboxylic acids, alligators for aldehydes, keep for ketones, all for alcohols, animals for amines, and then excited for ethers. Right. So just remember, the highest priority functional group forms the end of the name as the parent chain. All other functional groups will be substituents.
Functional Group Priorities - Online Tutor, Practice Problems & Exam Prep
Functional Group Priorities Concept 1
Video transcript
Functional Group Priorities Example 1
Video transcript
Here it says to provide parent chain names for each compound. In A, we have two functional groups present. We have an amine here and then we have an alcohol. Remember, the priority when it comes to functional groups has alcohols having higher priority than amines. Because of that, the parent chain is the one that's going to include the alcohol. And if we just name the alcohol within a vacuum, meaning we're not paying attention to the amine portion, what would the alcohol chain be called? Well, we'd start numbering from the end closest to the OH, so 1, 2, 3, 4, 5, 6, 7. The alcohol is on carbon number 1, so that'd be 1, and then 7 carbons is hept, and then it's an alcohol, so heptanol.
For the next one, we have a carboxylic acid group here and then we have a ketone group here. Remember, carboxylic acids reign supreme. They are the highest priority functional group. So, we're going to pay attention to that. So, if we're just looking at the carboxylic acid part and ignoring the ketone because we're just concerned with the parent chain, what would it be called? So we would say it'd be 1, 2, 3, 4. Four carbons here would be butanoic acid. Now we have a methyl group attached, we have a ketone attached. They also be incorporated into the name as well. But for right now, we're just concerned with what the parent chain would be. So again, remember, the highest priority functional group forms the parent chain name. Everything else will be a substituent.
Substituent Prefixes Concept 2
Video transcript
Now we're going to say if a functional group is named as a substituent, then it must use the prefixes listed below. So let's say that we have an ether portion that is a substituent. It'll be called an alkoxy group. Now, what do I mean by that? Well, let's say that the ether portion was an OCH3. CH3 is methyl, but because of the oxygen present, it would become methoxy. If we had an ethyl group attached to the oxygen, it's no longer ethyl; it's ethoxy. So that's what we mean by an alkoxy. Next, if we had an amine group, it'd be called amino as a substituent. And alcohol as a substituent is called hydroxy. And then finally, if we had an aldehyde or ketone as a substituent, they would be oxo. So keep these names in mind when each of these functional groups becomes a substituent.
Substituent Prefixes Example 2
Video transcript
So here it says provide the systematic name for the given molecule. Remember our memory tool. We're going to say here, "Cool alligators keep all animals excited." Here, that would mean that our ketone here would have higher priority than our alcohol. So our alcohol will be a substituent. Because the ketone has higher priority, we're going to start numbering from the end closer to it. So, we're going to say here 1, 2, 3, 4, 5, 6, 7, 8. Oh, when it's a substituent, it's called hydroxy. It's on carbon 7, so this would be 7-hydroxy. The ketone carbonyl is on carbon 3, so it would be 3. It is an 8 carbon chain, so it's octen, and then remember it's not octane anymore, since it's a ketone, we change the 'e' ending to -one, so it becomes octano. So the IUPAC name or systematic name of this structure would be 7-hydroxy-3-octanone.
Provide IUPAC name for following.
4-amino-3,3-dimethylpentanoic acid
4-amine-3-dimethylpentanoic acid
2-amino-3-dimethylpentaneoic acid
2-amine-3,3-dimethylpentanoic acid
Provide IUPAC name for following.
4-propoxypentanal
3-ethoxybutanal
2-ethoxypentanol
4-ethoxypentanal
Draw a structure for 7-oxoheptanoic acid.