Naming Amides Using IUPAC Nomenclature for Organic Chemistry LEAH FISCH: Leah here from leah4sci.com. And, in this video, I will show you how to name amides. An amide is a molecule that has a carbonyl or a carbon double bound to an oxygen attached to a nitrogen group such as NH2. Don't confuse the amide with a carbonyl bound to an OH, which is a carboxylic acid, or a molecule that has a nitrogen bound to the R group without a carbonyl, which is simply an amine. The amide functional group is a carboxylic acid derivative. That means, if you start with a carboxyl, remove the OH, and simply replace it by something like NH2 or NR2, you get your amide. When naming amides, you simply drop the oic acid from the carboxyl naming and replace it with the suffix amide. We'll start with the simple example by identifying and highlighting the parent chain. The amide is understood to be a primary functional group, which means it shows up in the beginning of the molecule and gets the number 1. I have two carbons in my parent chain for a first name of eth. Only single bonds gives me a last name of ane. And the carbonyl bound to the NH2 gives me the suffix amide. I don't include the number because it's understood to be number 1. And, since amide starts with a vowel, I drop the E in ane for a final name of ethanamide. When you have a substituted amide, you treat it the same way and break it down using my puzzle piece approach. We first identify and highlight the parent chain and number it so that the amide gets your number 1. Having four carbons gives you a first name of but, and only single bonds gives you a last name of ane. We have a one-carbon substituent on number 3, which gives me the prefix 3-methyl. And the carbonyl bound to nitrogen gives me the suffix amide. Drop the E in ane for a final name of N-methylbutanamide. When the substituent occurs on the nitrogen, rather than the parent chain, you treat it the same way, but, instead of having a number of preceding your substituent, you have the letter N. For this molecule, we have a total of five carbons, which gives me a first name of pent. Only single bonds gives me a last name of ane. Carbonyl bound to a nitrogen gives me the suffix amide. And the one carbon group attached to the nitrogen gives me the prefix N-methyl. I drop the E in ane for a final name of N-methylpentanamide. When you have multiple substituents off your nitrogen, you treat it the same way. Just be sure to include the appropriate prefix. For this molecule, we have a total of three carbons in the parent chain for a first name of prop. Only single bonds gives me a last name of ane. Carbonyl bound to nitrogen functional group gives me the ending amide. Since I have two methyl groups coming off of the end, I add the prefix N comma N-dimethyl to show that both methyl groups come off the end and di because I have two. I drop the E in ane for a final name of N,N-dimethylpropanamide. Notice that we have a comma between the two N's and a dash between the N and the name. And that's because, even though the letter N is not a number, we treat it as if it's a number to show where the substituents are attached. So think of this as the number N, rather than the letter N. In this example, we have a methyl group coming off the parent chain and off the functional group. We start by highlighting and identifying the parent chain and get a total of six carbons for a first name of hex. Only single bonds in the parent chain gives me a last name of ane. And the carbonyl bound to N functional group gives me a suffix of amide. I have two methyl substituents, one coming off the nitrogen and one coming off the carbon chain. And so I include the prefix 5 comma N-dimethyl. This is to show that I have one methyl group on the parent chain and one methyl group on the amide substituent. Numbers always precede letters, and that's why you have the 5 followed by the N. You drop the E in ane for a final name of 5,N-dimethylhexanamide. When you have more than one amide, you treat it the same way, but simply include the prefix di before the functional group to show that you have two. Since this is a symmetrical molecule, I can number from the right or the left. I have a total of eight carbons for a first name of oct and only single bonds in the parent chain for a last name of ane. Given that the amide is a terminal functional group, if we have two in the molecule, we assume it shows up on the first and last carbon. And so both numbers can be omitted. And so we add the suffix diamide, simply indicating that we have two amides on this molecule. Putting the pieces together, we get a final name of octanediamide, omitting numbers for the functional groups and, also, keeping the E in ane because the consonant D in di separates between the two vowels. We'll end with an interesting example. At first glance, we appear to have a symmetrical molecule. However, on the right, we have a carbonyl next to the NH2, but, on the left, we only have an NH2. The parent chain for this molecule contains a total of five carbons where the amide is higher priority and, therefore, gets the lower number. A total of five carbons gives me a first name of pent. Only single bonds gives me a last name of ane. A carbonyl bound to an NH2 on the first carbon gives me the suffix amide. The NH2 group or the amine is not the highest priority here. And so, in place of the suffix amine, we demote it from functional group down substituent with a prefix of 5-amino. We drop the E in ane for a final name of 5-aminopentanamide. In upcoming videos, I will show you how to name aromatic compounds. Are you struggling with organic chemistry? Are you looking for information to guide you through the course and help you succeed? If so, download my ebook, 10 Secrets to Acing Organic Chemistry using the link below, or visit leah4sci.com/orgosecrets. That's O-R-G-O secrets. For information regarding online tutoring, visit leah4sci.com/orgotutor. That's O-R-G-O tutor. If you enjoyed this video, please give it a thumbs up and even share it with a friend or two. If you have any questions regarding this video, leave a comment below or contact me through my Facebook page at facebook.com/Leah4sci. There will be many related videos posted over the course of the semester. So go ahead and click the Subscribe button to ensure that you don't miss out.