naming carboxylic acids and their derivatives gonna be the topic of this first lesson in a whole chapter on carboxylic acids in their derivatives and uh just so we're clear these derivatives include acid halides like acid chlorides and bromides acid anhydrides esters amides and nitriles now one quick thing to note we're only going to be naming these carboxylic acids and derivatives as if they're the highest priority function group in the molecule and that's not necessarily true if you had a carboxylic acid and an amide well the carboxylic acid would be higher priority and the amide would be named as with a prefix as a substituent well we're not going to do that most of you guys are never going to encounter any of these as anything other than the highest priority functional group now for those who take in my premium course if you check out the ochem one final exam review there's a comprehensive or organic nomenclature review and if you check that out the handout there does include those prefixes just from the odd chance some of you see them but i'm not going to include them there again 99 of you are never going to see these function groups named as anything other than the highest priority functional group now this lesson is part of my organic chemistry playlist i'm releasing these lessons weekly throughout the school year so if you want to be notified every time i post a new one subscribe to the channel click the bell notification okay we are going to name these in descending order of priority so these are the head honchos on your your priority list of organic uh functional groups and their nomenclature and so the highest one that's going to be carboxylic acids and that's what we're going to start with first and when you name a carboxylic acid so as with all these derivatives we'll find out they are always anchored to the end of the chain and so as a result when you name them as such so the carboxyl carbon here is going to be carbon number one and because it's carbon number one that is and it has to be at carbon number one that's never going to be included as part of the name here so in this case a three carbon chain is propane and in this case the suffix is oec acid so we're going to start off with propane and because oec acid begins with a vowel sound we'll drop off the e and we'll throw on that suffix oec acid and this is propanoic acid so in just a word to the wise for three carbons sometimes you'll see it written with a common name propionic acid might be worth knowing same thing with two carbons ethanoic acid more commonly called acetic acid and then four carbons butanoic acid also commonly called butyric acid so just in case you see any of those common names now if you've got a carboxylic acid on a ring special case we saw something similar with aldehydes so if this was just an h over here and was an aldehyde this would be cyclopentane carbaldehyde well in this case it's a carboxylic acid so it's cyclopentane carboxylic acid cool just a special case if your carboxylic acid is directly attached to a ring so now we'll move on to acid anhydrides here and uh if you hear the word anhydride that usually means like without water having water removed or something along those lines and we can see why here so if you take a couple of carboxylic acids and put them together you can remove the h on one and the oh on the other to form water and then when you put them together you get this acid anhydride now it's not necessarily how they're formed although they sometimes could be so but not usually so but it is kind of how they're named so this acid anhydride if we go to name it you got three words you're gonna name it based on the carboxylic acids uh it is composed of named in alphabetical order so this is butanoic acid this is propanoic acid so we'll say butanoic first and so this is going to be butanoic and then propanoic second word and then third words just anhydride cool so butanolic propanoic anhydride now this is what we call an asymmetric anhydride where the two sides of of the anhydride are made from two different carboxylic acids so but that's not necessarily going to be the case in fact it's not usually the case you're often going to have symmetric anhydrides and for a symmetrical anhydride like this one right here so if you kind of follow the same thing here well that both sides here come from propanoic acid and you'd say propanoic propanoic anhydride well to kind of you know prevent such redundancy for symmetric ones you only use the name of the carboxylic acid once and so this is just simply propanoic anhydride cool so we've got esters next in a priority ranking so carboxylic acids then anhydrides and now esters are next so and esters are going to be kind of broken up in two parts here and you've got your ester functional group here and there's the carboxyl side which is the carbon chain containing the carbon double bonded to oxygen so it also includes this auction we'll kind of break it up right there if you will so and then this guy right here cool so it turns out there's two words for the ester and the first word is just whatever you know alkyl group is on the other side of that oxygen right there and so in this case that's just going to be an ethyl group and that's the first word so we've got ethyl so and then this guy right here the rest of it is actually named as the conjugate base of this carboxylic acid and so in this case we've got a one two three four carbon carboxylic acid that's butanoic acid but the conjugate base is going to end with an ate so the ick becomes eight kind of like we did with nitric acid and the nitrate ion it's conjugate base same kind of thing so it's if if the four carbon carboxylic acid is butanoic acid well then this conjugate base is the butanoate ion and obviously i know we have a methyl group here we've got to throw in there as well and so in this case this whole thing is 3-methyl so right there and then the butano-8 cool and there's your name as an acid ester here so two words again ethyl three methyl butanoate and i want to make sure i put one that had an extra substituent over here so you could see the difference in why this substituent gets its own separate word but any substituents on the parrot chain itself are going to be named as part of that parent chain too so now we've got acid halides next also called acyl halide same thing so we've got an acid or acyl chloride and an acid or acyl bromide here in this case and gonna work the same way in principle number the longest chain so one two three and that's propane so cool and then your suffix for one of these is oil oil and since that begins with a vowel sound we'll drop the e on propane so propane oil and then either chloride or bromide so this is propanol chloride and the second one here propanol bromide cool all right so we've got amides next on the list so again carboxylic acids anhydrides esters acid halides and now amides so here we've got a very simple amide here primary amide we say in this case it's got three carbon chain so and the suffix for an amide is just amide so we're going to say propane and because the amide suffix begins again with a vowel sound we'll drop that e on propane and just say amide and so this is just propanamide now i want you to see the difference here between these next two here so once again we've got a three carbon chain so one two three and now we've got a methyl group on carbon two and just like with any other functional group we'll put those uh substituents named them out front and so here we've got 2-methyl propanamide cool and didn't really care about the second one truth be told but i wanted to see the contrast with this last one here so one two three so i've got a three carbon chain again and we've got this extra methyl group right here so and this nitrogen even has room for another carbon you know bond if we had another alkyl group we call this a secondary amide so and what happens when you've got an alkyl group coming off your nitrogen here as well so well we've got to say that we've got a methyl somewhere but it's not attached to one of the carbon numbers of the parent chain it's attached to the nitrogen and so this is a case where we actually use the nitrogen as the chain locator and so this is going to be n-methyl the capital ends that actually functions as a chain locator typically your chain locators are numbers but here it's going to be a capital n so and then again propanamide cool that's what you need to know about naming amides all right so the last carboxylic acid derivative we've got here are the nitriles so they've got that carbon nitrogen triple bond the hallmark and when they're not drawn out you see that cyano group pretty easily but these are nitriles and once again they're always going to be located at number one they're always going to be at the end of the chain and i just want to make sure you've seen it both when the carbon nitrogen triple on is formally drawn out or when it's not so it's the same either way in this case your longest continuous chain and you have to include that carbon oftentimes when you draw it like this students will only count the carbons that aren't explicitly drawn and forget that no no that counts as one of the carbons of the carbon chain as well in that cyano groups that's why i wanted you to see it both ways and so in this case we've got three carbons that's propane if i can spell here cool and it turns out that the suffix for nitrile is just nitrile now nitrile begins with a consonant and so as a result we're not actually going to drop the e there on propane but this is simply just propane nitrile simple as that if you found this lesson helpful would you consider giving me a like and a share best thing you can do to make sure that other students get to see this lesson as well if you're looking for the study guide that goes to this lesson if you're looking for practice problems in naming carboxylic acids and their 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