hi friends in this video I'm going to make our upse naming of organic compounds really easy for you questions on naming of organic compounds always comes in exams so I'm going to share some tips and tricks of how to write the IU pack name I hope after this video you will find the IU pack name as easy as writing your own name and if you like this video do share it out with your friends and don't forget to try the quiz and the top three questions on this topic links are given below the video there are some important rules that we need to follow for IUPAC naming I'll show you the rules with the help of some examples I recommend you to sit with a pen and paper so let's go ahead and do this are you PSE naming together let's start with this simple example so what do we have here to name this compound you need to first find the longest continuous carbon chain which is this two carbons here now go ahead and number it forward and backward now why do we do the backward numbering we'll discuss that later in the video as you can see this compound has two carbons so what is its name going to be remember there's a table if there's one carbon then the name starts with met two carbons the name starts with Earth three carbons it'll start with prop four carbons buuuut and so on so the name of this compound will start with Earth and what type of bonds are there in this hydrocarbon so you need to look at the bonds between the carbon atoms and as you can see there's only a single bond here so this hydrocarbon is an alkane so the name will be eat-in so that is the IU pack name of this compound it's Ethan so what we have to do look for the longest carbon continuous carbon chain number eight forward and backwards and find the name based on it it was earth and since there are only single bonds it's an alkane so it's going to be eat-in now let's go ahead and take a look at this example so let's apply the same rules we are going to find the longest continuous carbon chain which are these three carbons and we'll number it forward and backwards so three carbons means the name is going to start with that's right prompt and is this a propane no because there's a double bond here so there's a single bond between these two carbon atoms but there's a double bond between these two carbon atoms so it's an alkene so the name is going to be drop-in and if we had a triple bond here instead of a double bond what will the name be that's right it would have been prop I mean okay so what we learnt here is that you need to look at the longest continuous carbon chain look at the number of carbon atoms once you've numbered it forward and backward find the name based on the number of carbon atoms and also the type of bond for these hydrocarbons let's take a look at this example what will be the IUPAC name of this compound again let's find the longest continuous carbon chain which is this one and let's number it forward and backwards so it's a five carbon chain and we are going to do the forward and backward numbering so five carbon means the name is going to start with pent right and since there are only single single bonds between the carbon atoms this is an alkane so what is the name it's to be pentane right so this is a simple one but now let's say the five carbon atoms are arranged in a cyclic structure something like this and to fill in the let's fill in the hydrogen's so that carbon has all the four bonds satisfied so one two and two hydrogen's same way here so what will be the name of this cyclic compound so the cyclic compound the name starts with the word cyclo so remember it's going to be cyclo not psycho and since there are five carbon atoms here again it's going to be cyclo pentene paint because five carbon atoms and only single bonds so it's a cyclo pentene now let's take a look at this compound so this also has five carbon atoms but remember we need to find the longest continuous carbon chain so it's going to be this one you can't go up like this and come down so let's number the longest continuous carbon chain and as you can see there are four carbon atoms here so if we ignore this attachment of ch3 for a moment what's the name going to be four carbon means it's going to be Butte and since there are only single bond between the carbon atoms it's a butane so that's simple now let's look at this ch3 so ch3 as you may know is an alkyne because the definition of alcohol is it's an alkane minus one hydrogen so if this had been ch4 but we've removed the hydrogen so we have ch3 so if it was a ch4 the name would have been methane one carbon atom right but this will be now called me time right because it's an alkyne and the alkyl name comes in the prefix so you have to put it over here in the beginning of this name so we have basically a meat aisle butane here but now this methyl could have been here or it could have been here or here so we also need to give its position and the position is based on this numbering that we have done so what number should we give it it's on number 2 or 3 but you need to choose the smallest number so it's going to be 2 methyl butene okay so that's the name of this compound but let's say we had another ch3 over here so can you guess what it'd be the name here so let's work it out again first the trick is ignore these attachments so it's basically a butane and we have two methyls in here so that's going to be a diamond time and we also need to specify the positions of the methyl groups so here you can't say I can't choose 2 & 2 because I want to choose the smallest number you either have to go with the top the forward numbering or the backward numbering so it's going to be 2 comma 3 or if you use the backward numbering it will be 2 comma 3 so both the numbers are same we chose we have to choose the smallest number so it's same anyways so we are going to write it's 2 comma 3 dimethyl butane now note some important points here between the number and the letter there's always a dash as you can see here or here so between the number and a letter and if you have two numbers like here there's a comma in there can you see the comma so this one would be 2 comma 3 dimethyl beauty that's the are you pack name of this compound now let's take a look at this compound so what's interesting here is that there is a chlorine in here but again first ignore the chlorine and look at the law this continuous carbon chain so let's go edit number it forward and backward and we have one two three four five carbons and I am going to number it backwards also so if you know chlorine what is the basic name here it's five carbon so that's a pent and as you can see there are only single bonds here so it's a pentane now this chlorine is a halogen and so that's our functional group here so we have the halogen functional group and remember for halogens and for the al Kyle's that we had done the name goes in the prefix so it's going to be a chloro pentane not chlorine pentane it's chloro painting so that's the way are you pick-ups a name is done and we also need to give the position so what position of chloro should i give you is it going to be five Torro no it's one chloro because we choose the nearest number the smallest number here but there's no need to actually write one chloro here because the number one is not necessary so simply the name is going to be chloro pentane but if the chlorine was here then the name would have been too - chloro pentane right now let's take a look at another example so let's say again we have five carbons here and we have a chlorine in here a chlorine in here and let's say bromine in here I'm not drawing all the other hydrogen's so again we'll number our carbon chain forward and backwards so it's five carbon we ignore this for a moment so that's a simple way to do it so you'll have a pent and only single bonds pentane now again we have some halogens in here so there are two chloros and a bromo right now there's another rule that comes in here when you have a bromo and and a chloro you need to go in alphabetical order so B comes before C you shouldn't consider the dichloro the D is not important we are comparing bromo and chloro so the name bromo will come here first so there's a bromo and there's a plural sorry dichloro right so there's a bromo and dichloro but we also need to get the numbering and remember we need to choose the smaller numbers so we won't go for this scheme we'll go for the backward scheme so you can see that there's a 1 comma 2 dichloro and a 3 bromo so I'm going to rewrite this name again as so let's cancel this out it's going to be 1 comma sorry it's going to be 3 bromo right so the bromo is at position number 3 and after that we have 1 comma 2 dichloro correct and 19 so note these things carefully that between the number and the letter you can see there's a dash between the numbers there's comma and there's a number and a letter here so again a dash and we went alphabetical order bromo be came before plural so you can see it's a three bromo one comma two dichloro pentane all right let's try the next one here so what's the name gonna be again let's number the longest continuous carbon chain so we have four carbons here so the name will definitely have Butte in it and there's a double bond so is this compounds name going to be beauty no because the double bond is not at the first position or over here if you counted the one from here so we also need to give the position of the double bond so how do we do that the double bond is between two and three so we'll choose the smaller number and say the double bond is at position two so the name is going to be Butte to in because we are giving the position of the double bond sometimes you may see this compound written as 2 butene also but usually this is the recommended style where we give the number in the middle here so it's 2 in Butte two in okay now let's try this compound so here what do we have we have a five carbon chain and there are some interesting triple bonds here so you can see that there are two triple bonds so is this going to be a pen tine no because they're two bonds so first the names going to start with pent because there are five carbon atoms here and it's a die ein because they're two triple bonds so I'm going to write that here it's a pent die I'm but I need to specify the position of triple bonds so what's the position going to be we can say the triple bond is between two and three and four and five but that's using the bigger numbers so let's go for the smaller numbers so we'll start counting from here so the triple bond is between one and two and three and four so we will use this position numbers because we are saying the triple bond is at position 1 and position 3 so the name is going to be paint 1 comma 3 III and again between the letter and the number there's a dash and between two numbers there's a comma in here alright let's name this guy now now what's interesting here is there's the H functional group so this is an alcohol but again to simplify things we are going to ignore which and look at the longest carbon chain here so let's number it here forward and backwards so they have four carbons so basically the name is going to be a butte it's going to start with butte and if the alcohol wasn't there the name would have been butane but you know that alcohol and other functional groups that we are going to talk about their name comes in the suffix the prefix was for al Kyle's and the halogens so this alcohol name will come in the suffix and the name isn't ends with oil now when you add oil you need to remove the e so this oil gets added to the name and the name basically becomes butanol so remember the is removed and we attach the suffix om and what is the position of butanol it's at position 4 but we'll choose the number 1 here because that's the smallest number so it's basically butan 1 all or basically butanol because we don't have to write the number 1 now let's say the H was at a different position so let's say we had something like this and the witch was here and rest of course our hydrogens so what will be the name of this compound again we number our longest carbon chain right so this will be Butte it will start with Butte and the name would have been butanol but the position of H is on two because will not take three that's the larger number so it's basically a butan two all or sometimes you might find it written as 2 butanol but usually this is the preferred way of numbering it butan 2 all now let's try to name these two compounds earlier we had seen the alcohol functional group here also there's a functional group so do you know the name of this functional group which has C double bond o NH that's right it's called aldehydes and what is the functional group on this compound this is a functional group and it's called ketone so both the functional groups have C double bond o on them so what's the main difference here the aldehyde group is always at the end so either on this carbon or it could have been here okay because it ends with an H but the ketone group is interesting because the ketone group must have at least one carbon on both the sides so that's an important difference to remember because the functional group decides the property of the compound and of course its name so let's try to name this guy so again we'll apply the rule and look at the longest carbon chain and one important point to remember is even the functional group carbon needs to be included in the counting okay so it's five carbons including this one and we'll also reverse number it so this functional group wasn't there it would have been a pentane right the compound would have been five carbon paint and only single bonds are there if we ignored the functional group so it would have been pentane but the rule is to delete the e and add the suffix in the name for this function group and it's an aldehyde so we add the al to it so what will be the name of this compound then terminal and it's at position one the smallest number so it's basically Penton one eye or simply fentanyl okay is that clear now let's take a look at this compound so here we have three carbons and will include the carbon of the functional group so it's a three carbon chain so the name will be propane right if ignore the functional group but again the rule is will remove the letter e and add for the ketone we need to add own so what's the name going to be proper known now you might be thinking we need to include the number also right because the functional group is at position two so you might be thinking the name will be proper to own or to proper known but know the name is simply proper known why because one propanone or three properly known is not possible because if I move this ketone group to this side or this side if it becomes on the end carbon what will you become it'll be an aldehyde so only possibility with three carbon is to propanone so we simply write it as proper known now let's take a look at this example I have written this in the condensed form because the whole structure with the hydrogen's is not expanded here again you should look for the functional group and can you see it it's COOH so this is a carboxylic acid I'm just going to write simply acid here and again let's count all the carbons in our longest carbon chain so we have five carbons and remember we need to include the carbon in the functional group also and let's reverse number eight here okay so if we ignore the functional group the name would have been pent because five carbons and all have single bonds between the carbons so it would have been pentane right but this functional groups name will come in the suffix and for acid it's going to be the suffix is going to be weak acid that gets added so we are going to delete the e and add weak acid here so what is the name of this compound it's going to be pentanoic acid right and we don't have to give the position of this functional group because it's at position 1 so it's Penton 1 oak acid or simply pentanoic acid now let's say we have a chlorine over here so I'm going to remove one edge and let's add a chlorine in here so what is the name of this compound B so it's basically a pentanoic acid and the halogen comes in the prefix so it would be a chloro pentanoic acid but we need to do the numbering right so what number should we choose if we look at the smallest number we will think of writing as 2-chloro pentanoic acid but that's the wrong answer let me explain you why because in this compound can you see that there are two functional groups an acid and a halogen and then there's an important priority order that we need to follow so let me write down the priority list here so what is the priority list that you need to know so we have on the top priority we have the assets so that's co h then we have aldehydes followed by ketones then alcohols then you have the triple bond double bond okay and then you have the halogens so things like chloro bromo right and then you have the alkynes so things like methyl ethyl so these are the highest priority so this is our priority list here and the top ones are at higher priority than though and this one is at the lowest priority and easy to remember is this one has the most atoms one two three four so that's the top priority here this has three this has two and this one doesn't have carbon and you know in organic chemistry carbon is the king so that's alcohol then you have the triple and double bond followed by this functional group of halogens and then the al-qaeda's and remember these guys were added as prefix in the name so the prefix fellows come down at the priority list and all of these affect the suffix of the name so you can note down this important priority list and the numbering will be based on that so let's apply this for our compound here so we have acid and a halogen so according to our priority list acid gets the top priority so he wants position number one right so we need to follow this numbering scheme not this one and the halogen is at position 4 so basically what is this compound it's a 4 chloro Penton 1 auric acid right so we can simply write that us instead of a 2-chloro it's going to be a 4 chloro pent an but i won't write one because it's not needed so it will just be for chloro pentanoic acid so this is an important thing we've learned that when there are multiple functional groups we need to apply a priority list to determine the numbering here here's another example for you why don't you pause the video and try writing the IU pack name yourself for this one so what is the answer you got is it to Ethel and three metal one two three four five six hexane so is this your answer actually this answer is wrong so what is the right answer here let's take a closer look so if you look carefully this is not the longest continuous carbon chain why because this one has six carbons but if you go like this then can you see there'll be two three four five six seven carbons so the longest continuous carbon chain is this one so it's easier if we expand this one and write it as right so just expanded the a tile there for you and let's number our longest carbon chain here so four five six seven and again backwards one two three four five six seven right so this is not basically your hexane it's a heptane right and what are the attachments in front of this name because you can see the attachments or the substituent's we have here are two ch3 s right so that's basically and you know CH 3 is the alkyl group so it's a dimethyl so we have a dimethyl in front of the name here the prefix part and what are its positions it's at position 1 2 3 & 4 if we number this way so 3 & 4 here and if we go this way it said 4 & 5 so again we will choose the smallest number which is 3 & 4 so the name is going to be 3 comma 4 dimethyl heptane so that's our correct answer here ok let's try this one now here we have folk and can you see the functional group here what is the functional group that's right it's a ketone because you have C double bond o and carbon on both sides right so let's number our longest carbon chain 1 2 3 4 and reverse 1 2 3 4 ok so if you ignore the functional group it would have been a butane right but there's a functional group in there so I'm going to delete the e and you know in ketone the own gets added so it becomes a butanone and what is the position of the functional group it's at position 2 so that would make it a butan 2 own right but there's something interesting here if you write this name it's probably fine but strictly speaking if you look here if I shift the double bond over here then what will the main be it's not going to be butane 3 on again now we will take the smaller name a smaller number I mean so it's again going to be butan 2 own so just like propanone 4 4 carbons also only one ketone is possible which is butan to own or simply butanone so this is the best answer here that the name is just butyl because you can't have the double bond all at carbon 1 or 4 because then it will become an aldehyde it will be at the end carbons and if you put it at 2 or 3 it doesn't matter the name is the same butan to own or simply butanone and here's our final example for this one I want you to write the IU pack name yourself so do let me know your answer by putting it in the comments below I hope the IU pack naming is crystal clear to you now here is Marie of the rules that we learnt the first thing is to find the longest continuous carbon chain and remember to number it forwards and backwards then you should check for functional groups whether they are double bonds or triple bonds present in the compound and add the name as the prefix or the suffix and remember to use the priority list that we talked about the alphabetical order and using the smallest number to give the position numbers so go ahead and use all these rules and find the answer for this compound and do let me know your answer by putting it in the comments below and if you found this video useful to share it out with your friends and if you haven't subscribed to my youtube channel already hit the subscribe button right now you can also check my Facebook page and do check out my website mono chai academy.com for the quiz and the top three questions on this video I'll put the links in the description below thanks for watching