Transcript for:
IUPAC Naming Masterclass

Hello guys, this is Play Chemistry and you are watching IUPAC Naming Masterclass. In this video, our task is to cover the complete IUPAC naming in just one video. We will cover A to Z rules step by step without skipping anything. We will do everything, naming of branch chains, complex chains, multiple bonds, functional groups, poly functional groups, cyclic compounds, aromatic compound. Everything in this single video. We have optimized this topic to such an extent that everything can be completed in just 1-1.5 hours. So let's start the most important part of Organic Chemistry, IUPAC Nomenclature. First example, we will first name this compound. So look at this compound. This compound has 4 carbons, 1 chlorine and 1 OH. And all the bonds in its carbon chain are single bond. So let's do its naming step by step. For 4 carbons, we use butane, meth for 1 carbon, eth for 2 carbons, prop for 3 and butane for 4. Here we have 4 carbons, so we will use butane. Now look at the carbon chain of this compound. All the bonds in this carbon chain are single bonds. And for single bond, we use ane. If all the bonds in the carbon chain are single bonds, then use ane. If there is at least one double bond, use ene. And if there is even one triple bond, then use ane. So here we will use ane. So but plus ane gives butane. Now there are two functional groups in this compound. Which alcohol? and Cl is Chloro. Alcohol and Chloro are considered as main function group and Chloro is a substituent. For main function group we use suffix and for substituent we use prefix. Suffix is the part which we put at the end of the name. And prefix is the part which we put at the beginning of the name. For alcohol we use suffix Ol and for chlorine we use prefix Chloro. So Ol will be at the end of the name. And Chloro will be used at the very beginning of naming. There is a rule in naming that if the functional group starts with vowel, then we have to remove the E from the end. Because we can't use two vowels together. So remove the E from the end. Chlorine and alcohol, where are they used in the compound, that can make a difference in naming. Suppose Chlorine is used here, or Chlorine is used here. So we consider it as a separate compound. And if it is a separate compound, then its name should also be different. So, after doing numbering, it is important to tell us where is the Chlorine and where is the Alcohol. So, what is the method of numbering? So, let's do the numbering of this compound. Alcohol and Chlorine have higher priority. So, we have to do numbering in such a way that we take the Alcohol at the lowest location. So, let's do its numbering. First of all, we do numbering of the main chain's Carbons. And the numbering of the main chain's starting Carbons. It starts from the ending point or from the starting point. And we have to do numbering in such a way that the main function group gets the lowest locant. So here alcohol is the main function group. So according to this, we have to start numbering from this end. We will do numbering thoroughly in this chapter, but for this example, you just need to keep these things in mind. So this is correct numbering. Now look at the positions of all the substituent and functional groups. Here chlorine is in 3rd position, so we will use 3-chloro. And alcohol is in 1st position, so we will use 1-ol. So we will write its name as 3-chloro-butane-1-ol. Now one more important thing that you need to keep in mind. In naming, first letter is 1. always be capital. So C in Chloro is the first letter, so it will be capital. And apart from this, no other letter should be capital. So in all the upcoming names, you have to remember this. And this compound you can also write 3-chlorobutanol. This is because, if we don't mention the position of the ole, then by default, it will be considered as 1-ole only. So 3-chlorobutanol is equal to 3 chlorobutane 1 ole. So this was the naming. Now let's analyze this IUPAC name. Look at this naming. First of all, we mentioned substituent. After substituent, we mentioned number of carbons. And after number of carbons, nature of bond. And finally, function group. We will follow this order in all the organic compound naming. And if we simplify it further, So, this part is called prefix, this part is called word root and this part is called suffix. While naming, we will follow this order. Now, one more important example. This is a cyclic compound. Now, in this example and the previous example, there was only one difference. The previous compound was an open chain and this compound is a cyclic compound. Everything else is the same. So, first of all, let's understand this cyclic structure. If you write this compound by expanding, it will look something like this. Every corner of this cyclic structure represents a carbon. Here is the total. Total 6 corners means this compound has total 6 carbons. Now look at the edges of this cycle. The edge of this cycle tells us what type of bond is there in this compound. Single line means single bond, double line means double bond, and three lines means triple bond. Here, single lines are applied on all the edges. Means, there are only single bonds on this. So, the first structure is called bond line structure. and the second structure is called expanded form. So this structure has 6 carbons, all the bonds are single, and it also has alcohol and chlorine. So this is exactly like the previous one, but this time it is cyclic. First of all, we do its numbering, just like the previous example. So we have to do numbering with the carbon which has the main function group. And here the main function group is alcohol. So let's do the numbering. So, alcohol is at 1 and Cl is at 4. So, we will name it in proper order. First, prefix, then word root, then suffix. For chlorine, we use chloro. And since chloro is at 4th position, so we will write 4-chloro. And since it is a cyclic compound, so we will write cyclo for it. Now, since this compound has total 6 carbons, and for 6 carbons, we use hex, so write hex. Since in this compound, all the... All the bonds are single bond, so we will use ane. And since alcohol is the main function group, so we will use ole here. So the structure of this name is 4-chloro plus cyclo plus hex plus ane plus ole. So ultimately we will write it 4-chloro cyclo hexanol. So this is a typical IUPAC name. In this compound, there are all the components which can be in an IUPAC name. So the middle one is hex. We call it word root. Word root tells us how many carbons are there in the compound. There is a complete list of word roots which I will tell you later. After hex, we have ane. This part is called primary suffix. Primary suffix tells us whether there is a single bond in the compound, double bond or triple bond. For single bond, we use ane. For double bond, we use ine. And for triple bond, we use ine. After ane, we have and this part is called secondary suffix. Secondary suffix tells us which function group is used in compound. Before word root hex, we have written cyclo. Cyclo is primary prefix. Cyclo word tells us whether compound is cyclic or non-cyclic. If compound is cyclic, then use cyclo. And if compound is not cyclic, it is open chain, then don't write anything. Before cyclo, we have written chloro. And chloro is here secondary suffix. Prefix. Secondary prefix tells us which substituents are used in compound and which side chains are used. Chloro is a substituent in this compound so we have written it in the very beginning. So in coming compounds, you will observe this order. First we will tell side chains and substituents. And then cyclo if compound is cyclic. And then we will tell number of covens. And then we will tell if compound has single bond, double bond or triple bond. Or number of covens. In the last part, we will tell which function group is used in the compound. So, we are going to follow this order. Secondary prefix plus primary prefix plus word root plus primary suffix plus secondary suffix. And we can't alter this order. We can't change anything. Now in the next part, we will see the list of all word roots, prefix and suffix. So, let's see complete list of word roots, prefix and suffix in this section. So, first, we will see the list of all word roots, prefix First of all, let's see the complete list of word roots. If there is only one carbon in our chain, then we will use myth. If there are two carbons, then we will use ith. If there are three carbons, then we will use prop. If there are four, then we will use bute. 5 is pent, 6 is hex, 7 is hept, 8 is oct, 9 is non, 10 is dec, 11 is undec, 12 is dodec. You will only need 12. If you want to go beyond that, you can check this list. Next is primary suffix. So it is clear. It is ein, een or ein, based on number of bonds. Next is secondary suffix list. Secondary suffix is for function groups. So let's discuss complete list of function groups here. So first of all, COH means carboxylic acid. You will use Oic acid for it. CS3, CS2, COOH. Here you have to keep in mind that we will count the carbon of carboxylic as well. So here we have total 3 carbons and single bond in the chain. So we will use propane and for COH we use Oic acid. Because O starts with O which is a vowel, so we will delete E from AIN. So its correct name is Propanenoic Acid. CHO is Aldehyde and for Aldehyde we use L. So let's see this compound with three carbons, single bond and aldehyde. So this compound we will call Propanel. Now CO, so this is Ketone and for this we will use One. So see this compound. Both compounds have 5 carbons and all the single bonds are in the carbon chain and one is ketone. But the position of ketone is different in both. So let's do the numbering. In the first one, ketone is at second position. So we will name it as pentane 2-one. And in the second case, ketone is at third position. So it will be named as pentane 3-one. Now let's move to OH. You know it, it's alcohol and we use OL for it. We have used it in the previous examples. So we will not do it here. Now some new ones, which you might not have done in the 10th class. It is CONH2. This function group is called acetamide. and we use amide suffix for it. So, CS3, CS2, CO and H2. Again, 3 carbon and in carbon chain, single bonds and 1 acid amide. So, it will be written as propane amide. COCl, this is called acid chloride and we use oil chloride for it. CS3, CS2, COCl. So, what will be its name? Propanoyl chloride. Now next one is COOR. This is ester group. It has two parts. COO and R. So what is R? This is alkyl group. Let's see how it's named. 1 carbon alkyl, methyl. 2 carbon alkyl, ethyl. 3 propyl. 4 butyl. I hope you get this pattern. So, in ester, this R is alkyl. Now, let's come to the nomenclature. Look at this compound. This is ester. It has two parts. This part is written as alkyl and this part is written as alkanoid. The complete name will be alkyl alkanoid. So, look at this. This alkyl part, it has only one carbon. So we will call it methyl. Now look at this alkanoate part. This part has total 4 carbons. So we will use butanoate for this part. Combining both, we get methyl butanoate. So this is how we will name the ester. Let's do one more example. CS3COO CS2CS3. So divide this compound too. This time, there are 2 carbons in the alkyl part. So this part is called ethyl. Now look at the alkanoid part. Here there are two carbons. So it will be called ethanoid. So this compound is ethyl ethanoid. So this was ester. Now next functional groups. CN and NC. First one is cyanide and other is isocyanide. Both look the same but they are different. Look at these two compounds. One is cyanide and other is isocyanide. Cyanide is bonding with carbon. And isocyanide is nitrogen. So that's the difference between both of them. Now let's come to naming. Cn means cyanide. For this we use the suffix nitrile. So CS3, CS2, Cn. This compound has total 3 carbons. And due to cyanide group we will use nitrile. So its IUPAC name is propane nitrile. Now because nitrile starts with n, which is not a vowel. That's why we didn't delete e from n this time. So we will use the suffix nitrile. Let's name this isocyanide. There is no name for isocyanide in IOPSA. There is only common name for it. The writing method of this compound is alkyl isocyanide. So here we have two carbon alkyls. So that is ethyl and then right isocyanide. So this compound is ethyl isocyanide. Next is NO2 and ONO. Nitro and nitride group. There is a difference in bonding side in both groups. In Nitro, bonding is done with nitrogen and in Nitrite with oxygen. And both have different structure. Now let's come to the naming. For Nitro group, we use prefix Nitro which will come before the word root. Here we have Nitro and Ethane. So we will call it Nitro Ethane. CS3, CS2, ONO. ONO Nitrite, they also don't have any IUPAC name. But they have a common name. It is named as Alkyl Nitrite. Very similar to Isocyanide group. First part is called Ethyl and other is Nitrite. So it will be called as Nitro. Ethyl Nitrite. Now next is OH and SH. Alcohol and Thiol Alcohol. The way we use Ol for alcohol, similarly we will use Thiol for Thiol Alcohol. Let's do a quick naming. First one is called Ethanol and second one is called Ethanethiol. Now the next one is Primary Amine, Secondary Amine and Tertiary Amine. So what is the difference between all of these? Primary Amine has only one group. Secondary amine has two alkyl groups and tertiary amine has three alkyl groups. Now let's do their nomenclature step by step. Primary amine looks like this and we use suffix amine for it. So CS3, CS2, NS2. Look at this compound. Two carbons, single bond and primary amine. So we will write this compound as ethane amine. Next is secondary amine. Secondary amine has around two alkyl groups of nitrogen. So it's negative. Name is written in this form, analkylylalkenamine. Let's understand it with this compound. Its name is written in this form, analkylylalkenamine. Let's understand it with this compound. There are two parts in this compound. First one is main chain and other is side chain. Main chain is the one which has the most carbon. So, main chain will be this and this will be written as alkenamine. Now the second alkyl group that is left, that will be treated as a side chain. And that side chain will be For that we will write N-alkyl. So now in this compound, there are two carbons and amines in the main chain. So we will write it as Ethenamine. There is only one carbon in the side chain. So we will write it as N-methyl. So the name of this compound will be N-methyl Ethenamine. Now it is the turn of Tertiary Compounds. It is very similar to Secondary Amines. We will write it like this. N-alkyl, N-alkyl, L-keneamine. Secondary Amines have only one side chain. But Tertiary Compounds have only one side chain. There will be two side chains in the sherry amine. That's the difference. Everything else is the same. So again, we will make the main chain first. So the alkyl with 3 carbon is the longest chain. So that will be our main chain. So CS3, CS2, CS2N is our main chain. We will call it propanamine. CS3 and CS3, CS2 are side chains. We will name them as N-methyl and N-ethyl. Now because ethyl starts with E and methyl starts with M, So we will write it in alphabetic order. Ethyl first, methyl later. So the name of the compound is anethyl-anmethyl-propanamine. Now last functional group, anhydride. Let's name this compound. So first of all, count the number of carbon on both sides. On the first side, there are three carbons and on the other side, there are two carbons. So it will be named as ethanoic-propanoic-anhydride. And as you As usual, we have also taken care of the alphabetic order here. So you must have seen this format. Now let's come to the next example. Now there are three carbons on both sides. But we will not write it as propanoic, propanoic anhydride. We will simply write it as propanoic anhydride. Now it's time for secondary prefix. Let's see the complete list of secondary prefix. For whom secondary prefix is used? For side chains and substituents. So in this list, we will discuss about side chains and substituents. So first one is alkyl group R. So kyunki humne abhi kuch hi der pahle kiya hai so we will not go in details again. It is written as methyl, ethyl, propyl. So I hope you understand the pattern. Now the next one is RO. This is called alkoxy. So alkoxy is named like this. CS3O. This is called methoxy. Next one is called ethoxy. And this one is called propoxy. I hope you get this pattern. Now let's move to We use halogen, fluorine, chlorine, bromine, iodine. We use fluoro, chloro, bromo, iodo as a prefix for them. There are some more side chains like phenyl, allyl, isopropyl, isobutyl, secbutyl, tertbutyl. We will use these side chains in this video. Now the next stage is nomenclature. Now, let's talk about the rules of nomenclature. We will divide it into three parts. Main chain selection rules, numbering rules and naming rules. So, let's start with main chain selection rule. The first rule is longest chain rule. That means, whatever the main chain should be, that must be the longest chain. So, let's see this compound. In this compound, we can make the chain like this and like this. But ultimately, which chain should be in which chain? This is the longest chain. Obviously in the second one. So the second one is right and the first one is wrong. So this will be the 5 carbon chain, main chain and the rest side chain. So this one was a little obvious. But in case you get such a chain, then there can be a little confusion here. You can select main chain like this. But this will not be correct. We have to select the longest chain. So this is the longest chain. In the previous chain, there were only 5 carbons but in this one, there are total 7 carbons. So this is the longest chain and the rest will become side chain. Now let's move ahead. How to select main chain when there is double bond, triple bond or any functional group in the compound? Now in this case, this can be the longest chain so this chain should be considered main chain but it is not. Because there is double bond in this compound. So we must include double bond. include that in the main chain. So main chain bhale hi longest chain na bane but it must include double bond. So this is the correct main chain aur baaki sab hai side chain. Same rule tab bhi apply hoga jab compound mein triple bond ya functional group lagao. Let's see this compound. This can be the longest chain but as we know main chain mein functional group aur multiple bonds bhi aane chahiye. So this is the correct main chain. So having all this done, you know how to select main chain. Now look at this compound. This should be the longest chain. But if you make it like this, then it is also the longest chain. Both have 6 6 carbons. Now who do we consider as the main chain? So whenever we have this kind of conflict, then count number of side chains. The one who has the most side chains is the main chain. In the first one, there are two side chains. And in the second one, there is only one side chain. According to this, the first chain is the main chain and we will consider it correct. Second step, numbering. So the first rule is lowest locant rule. Locant, as we know from the name, Locant is location. Here, Locant tells us the location of side chains, substituents, functional group, double bond, triple bond. These locant should be lowest. Only then we will consider numbering correct. Now look at this example. This is our main chain and a side chain is attached on it, methyl. We have to do numbering like this. that methyl gets lowest locant. So let's do the numbering from left to right. In this case, methyl came in second position. Now number this chain in reverse order. In this case, the methyl came in the 4th position. CS3 is getting lowest number when we numbered it from left to right. So this is the correct way of numbering this chain. So in this case, there was only one side chain. Now let's see this case. Obviously, this is the main chain. Now let's start numbering. If we number it like this, then the lock end of both the side chains will be 2 and the lock end of third side chain will be 5. So in this case, the lock ends are 2, 2, 5. Now number it in reverse order like this. Now look at the Locant. The first side chain is on 2 and the other two side chains are on 5. So its Locants will be 2, 5, 5. So in this case, how do we decide which numbering is correct? So first of all, we have to look at the first Locant. If in both cases the first Locant is same, compare the second Locant. And if the second Locant is same in both, then compare the third Locant. So in this example, look at the first Locant. Both of them are getting locant 2. Now move to the next one. First case me locant hai 2 aur second case me hai locant 5. So obviously first one is getting the lowest locant. 2,2,5 is the lowest locant. So pehli wali numbering correct hai. And this is called lowest locant set rule. Now let's move on to the next example. If a compound has multiple bonds or functional groups, then they should get the lowest low end. In this structure, double bond should get the lowest low end. We are giving priority to double bond instead of side chain. So we are going to number it like this. Double bond gets second locant and methyl gets fourth locant. Now let's move on to the next example. This compound has a double bond and a triple bond. Here we will use lowest locant set rule. We have to do numbering in such a way that both of them get lowest locant. So you must have got the idea of where to do numbering by looking at the compound. Do the numbering from the left. Now let's do next example. This also has a double bond and a triple bond. To understand what is special in this, you have to do numbering. Now write its logands after numbering. As you can see, in the first case too, the logand is 1,4 and in the second case too, the logand is 1,4. So whether you do numbering from the left or from the right, you are getting the same set of logands. So this case is called equivalent numbering because both the numberings look the same but they are different. In the first case, logand 1 is going to double bond and in the second case, logand 4 is going to double bond. So this is the same Now, a new rule comes here. While doing numbering, double bond and triple bond have higher priority. So, we will give lowest lock-end to the double bond. So, the first numbering in which double bond got first lock-end and triple bond got fourth, that numbering is correct. I will like to bring your attention to the previous example. In this example, we followed lowest lock-end rule and here triple bond got lowest lock-end. This happened because the lowest locant rule is more important than any other rule. Now look at this example. Here we have not violated the lowest locant rule. Here we had a choice, so we gave the lowest locant to double bond. But if we don't have a choice, then simply follow the lowest locant rule. Now look at this compound. Here we have double bond as well as function group. The priorities of function group are among function group and double bond. So we have to do numbering in such a way that the function group gets the lowest locand. So look at this compound. We have to do numbering in this from the right. Only then alcohol will get the lowest locand. So this is the correct numbering. Chain terminating function group. CHO, COOH, COOR, CN, CONS2, COCL. We call these groups chain terminating function group. Ending means ending. This function group is located at the ending points of the main chain. That's why it's called chain terminating function group. Look at this compound. The first thing to do is to select the main chain. This is the longest chain but it's not main chain. Our function group should also be present in the main chain. Now see the COH. It is at the end point of this chain. So I hope you get the point of terminating group. Now it's the turn of numbering. The process starts from the carbon of the terminating group. So it will be numbered from carbon of COOH. So this is the correct way of numbering. So the numbering rules are done. We have done two parts of the IUPAC rule. Main chain selection and numbering. The next part is naming rules. Now it's time for naming. So let's start with this example. Let's select main chain and do the numbering first. So first of all let's write side chain and then main chain. This compound has two side chains, methyl and ethyl. Now first of all write ethyl or methyl. So here it is written as alphabetic order rule. All our side chains and substituents, we will write them in alphabetic order. Methyl starts with M and Ethyl starts with E. E comes first and then M. So this means that we will write Ethyl first and then Methyl. So we will write it 3 Ethyl 2 Methyl. Now it's time for main chain. Main chain has 6 carbons and all bonds are single. So we will call this hexane. So first we will write side chains and then main chain. So the name of this compound is 3 Ethyl 2 Methyl. Next Compound, select main chain and do numbering. Main chain ke alawa jo bhi bacha that are side chains. So here we have two side chains and both of them are the same. We have two methyl groups. So will we write two methyl, two methyl? No. Whenever side chains are repeated, we use di, tri, tetra for them. If two side chains are repeated, we add di. If three are repeated, we use tri. And tetra for four. So in this case, methyl is repeated twice. So we will add di so it's dimethyl. The correct way of writing this side chain is 2,2-dimethyl. Now we have to write main chain and because main chain has 4 carbons so we will write butane. So the name of this compound is 2,2-dimethyl-butane. Look at this compound let's do its naming quickly. First of all select main chain and do the numbering. Since we have repeated methyl three times, we will use trimethyl. We will write this compound as 2,2,4-trimethyl-5-carbons-pentane. Now look at this compound. First select its main chain. This compound has a methyl and an ethyl. Now how to number it? If you do numbering like this, then methyl will come in 3rd position and ethyl will come in 4th position. Now do numbering in reverse order. Ethyl got 3rd lock end and methyl got 4th lock end. So whether you do numbering from left or right, we are getting same lock end. So now we have a choice that we give methyl 3rd lock end or give ethyl 3rd lock end. So in this case, we will give lowest lock end to ethyl. which comes alphabetically first. So, from Ethyl and Methyl, Ethyl comes first. That means Ethyl should get lowest locant. So, the third locant should go to Ethyl. So, obviously, the second numbering is correct. So, the name of this compound will be 3-ethyl-4-methyl. Now, since there are 6 carbons in the main chain, so we will write it hexane. But keep in mind that from the lowest locant rule and alphabetic order of the compound, The priority of lowest locant rule is more. In this case, we gave the lowest locant rule to Ethyl because we had a choice. But if we don't have such a choice, then we will give priority to lowest locant rule. But don't violate lowest locant rule for alphabetic order. Now look at this compound. First of all, select the main chain and do its numbering. In this case, we have two methyl groups and one ethyl group. So in this question, we have two methyl groups. What is special about this? So let's do it and observe it. Here there are two methyl groups, so we will use dimethyl and the other side chain is ethyl. Now, which of dimethyl and ethyl comes first alphabetically? You can say that dimethyl starts with D and ethyl starts with E. So this means that dimethyl should come first and ethyl later. But this is not the case. Ethyl will come first and dimethyl will come later. This is because While looking at alphabetic order, we don't consider di, tri and tetra. Here in dimethyl, we will not consider the first letter D but M. So, this is why ethyl came first and dimethyl came later. So, for this reason, we will write 3-ethyl-2,5-dimethyl. And because there are 6 carbons in the main chain, so it will be written hexane. So, this is 3-ethyl-2,5-dimethyl-hexane. Now, it is the turn of multiple bonds. You know that for single bond we use IN, for double bond we use IN, and for triple bond we use IN. So, in this compound, there are 4 carbons and a triple bond. For 4 carbons we use Bute, for triple bond we use IN. So, it should be Bute plus IN. And it is important to tell the location of triple bond. So, let's do the numbering. So, triple bond came on the second locand. So, we will call this compound to I now next compound is compound me do do double bonds then to Jessica I'm sight change kill a die try tetra use cut it a to y'all pay me I'm die try tetra use current a is barham double bond killing a knee bulky die in use current a or a good teen double bond with a Tom try in use cut there to sub sepele car late a skin numbering numbering card in a kebab a double bond are a first position pay or do so double bond are a top third position pair so we will write but plus 1 comma 3 die So in this case, Dien is our primary suffix and whenever our primary suffix starts with a consonant, we have to add an a at the end of the word root. Because Dien starts with D, which is a consonant, so we have to add an a at the end of the buta. So the name of this compound is Buta. Now this compound. This compound has double bond and triple bond. So first we have to do its numbering. So we know that who will be given priority? Double bond. So start numbering from left to right. So this was numbering, now it's time for naming. So the way to write name is word root plus primary suffix plus secondary suffix. Now this compound can be written in two ways. As a derivative of alkene and as a derivative of alkyne. If we write it in the form of derivative of alkene, then it will come in the position of primary suffix, and in the position of secondary suffix. And if we write it in the form of derivative of alkyne, then it will come in the position of primary suffix. In will be in the position of suffix and in the position of secondary suffix. So now we have to decide whether we write it in the form of derivative of alkyne or in the form of derivative of alkene. Whenever there is a double or triple bond in the compound, we will write the compound in the form of alkyne derivative. That means in the position of primary suffix will be in and in the position of secondary suffix will be in. Now we have made five cars of alkyne, so for that we will use bent. and then we will write IN and then INE After numbering, double bond comes in first position and triple bond comes in fourth position So it will be written as pent 1 IN 4 INE Till now we have done side chains like methyl, ethyl, propyl But apart from these, there are many other types of side chains So let's see some other types of side chains So look at this one It has one carbon and double bond on linking side So normal one We call this compound as methyl but here there is double bond on linking site. So we call this compound as methylene. Now look at this compound. If this compound was normal then we would have written it as ethene. But here there is a linking site on ethene. So it will be called ethinyl. And we also call this compound as vinyl. So you can use any of these compounds. We call this compound as ethine. Now if a linking site is placed on this compound then what will it become? Ethane. If this is methylene, then what will we call it? Ethylene. But Ethylene is common name of Ethene. So we will not call it Ethylene, we will call it Ethylidene. This is not the exact reason, but you can remember it this way. Now it's time to use these side chains. Let's do this example. This compound has two double bonds and one triple bond. So the first thing is main chain selection. Main chain lock. longest chain and it should have maximum double and triple bond. So you can notice here that both double and triple bond cannot come at the same time in our main chain. But because we have to select the longest chain and it should have maximum double and triple bond in our longest chain, so this should be the main chain. So the side chain that came here is a special type of side chain, whose naming we have just done. Now let's do the numbering. Simply follow the lowest low control. So we have the first one here. So this is the numbering. First of all, we will write side chain. We have just discussed side chain. This side chain is called Ethinyl. So we will write side chain as 4-ethyl-ethyl. Now the name of main chain. There are 7 carbons in main chain. There is a double bond and a triple bond. So it will be named as a derivative of alkyne. So its name will be hapt-1-ene-5-yne. So the name of this compound is 4-ethyl-ethyl-hapt-1-ene-5-yne. Now functional groups. So let's start. with this one, so the first thing to do is to select the main chain so you know that our main chain should be longest and it should have terminating function group so this is the correct main chain and the remaining ones are side chain now it's time for numbering, so there is no confusion in numbering numbering will start from carbon of terminating group so let's do the numbering so this will be the numbering on second log n, there is one ethyl and one methyl so we will write it as 2 ethyl 2-ethyl, 2-methyl. And in the main chain, there are 4 carbons and aldehyde. So we will write it butanel. So the name of this compound is 2-ethyl, 2-methyl, butanel. Now look at this compound. This compound has a function group and a double bond. So in our main chain, double bond and function group should come together. So, this is the correct. Main chain and the remaining is side chain. Now it's time for numbering. We have to do numbering with the carbon which is close to alcohol. So this carbon is close to alcohol. So we will start numbering from here. So let's do the numbering. Here our side chain is ethyl. It is coming at third position. So we will write 3 ethyl. In our main chain, there are 4 carbons, a double bond and a functional group. So we will write but. plus in plus all and since double bond is in third position so we will use 3 in and here alcohol is in first position so we will write 1 all as you know that you can omit 1 so you can write 3 ethyl but-3 enol now last compound is this one it contains alcohol twice only and since alcohol is repeated here so we have to add ditrite tetra here as well If there was one alcohol, we would have used OL. But because there are two alcohols here, we will use DI-OL. So first of all, do its numbering. So, we have two alcohols in first and second position. So, we will write 1,2 diol. We have three carbons in our chain and single bonds. So, we will use prop and ane. So, this compound is written as propane 1,2 diol. Now, you can notice that we have not removed the e from ane. Why? Because diol starts with d and d is a consonant. Now let's talk about complex chains. We have done normal side chains till now. But now look at these side chains. Look at this one. Here there is a side chain on the side chain. Look at this one. Here there is a substituent on the side chain. And look at this one. Here there is a functional group on the side chain. And look at this one. Here there is a double bond on the side chain. So these side chains are not normal side chains. These are called complex side chains. In this section, we will learn to name complex chains. In these compounds, we have to name them twice. First of all, the complex chain and then the entire compound. So let's do some example and understand it. So start with this one. So the first thing is to select the main chain. So this is going to be the main chain. And this time the side chain is a complex chain. So let's do this. First, we have to name a complex chain. So, we will use the same rules that are used for normal organic compounds. So, let's start its naming. So, the first thing to do is to select a main chain in this complex chain. So, the first rule is that the main chain should start from the linking side. And it should be the longest chain. So, according to this, this is our main chain. And the remaining ones are the side chains. So, the side chains are here. 2 side chains. Now it's time for numbering. In complex chain, numbering always starts from linking side. So, no need to think much here. Number 1 goes to this carbon which is connected to linking side. Now it's time for naming. First of all, we will write side chain then main chain. So, here are 2 methyls at first locant. So, for them we will write 1,1 dimethyl. Now we will do naming of main chain. Main chain has two carbons, so we will use ith for it. And since it is a side chain, we will use i for suffix. So its name will be ethyl. So the name of this complex chain is 1,1-dimethyl-ethyl. Now next rule. Complex chains are always written inside a bracket. So put a bracket around it. So this is how we named the complex chain. Now its time to name the entire compound. So the first thing is numbering, and for numbering we will follow lowest, low and true. So this is the numbering, so complex chain came on 4th log end. So first of all we will write complex chain as 4,1,1 dimethyl ethyl. Now we will write main chain. Now here there is 7 carbon on main chain, so we will use heptane for this. So the name of this compound is 4,1,1 dimethyl ethyl heptane. Now next example, there is nothing different in this compound, but this time only 2 complex chains are used in compound and both complex chains are same. So you must remember what we used for normal side chains. For example, we used to write dimethyl when there were two methyl, trimethyl when there were three methyl. But in the case of complex chains, we don't use di-tri. For these, we use different prefixes. For 2, we use bis. For 3, we use tris. For 4, we use tetrakis. And for 5, we use pentakis. Since the complex chain has been repeated twice, we will use bis for this. So, we don't need to name this complex chain. It is exactly the same one that we named in the previous example. So, we call it 1,1-dimethyl ethyl. And because complex chain is repeated twice, so we will add bis. So it is bis dimethyl ethyl. Because both complex chain are on 4th lociant, so we will write 4,4 bis dimethyl ethyl. And because there are 7 carbons in main chain, so we will write haptane. So this compound is 4,4 bis 1,1 dimethyl ethyl haptane. Now name this compound. This question also has same complex chain. So let's see what is special about this. We have a complex chain and a normal side chain. Complex chain is called dimethyl ethyl and side chain is called ethyl. Now the question is, who will come first alphabetically? So you must remember that we used to write ethyl first from dimethyl and ethyl and dimethyl later. Because we did not consider di-tri-tetra. So if we had die methyl and ethyl written, then we would not consider D from die and would consider M. So ethyl would come first and die methyl later. So we used to do this for normal side chains. But in the case of complex chain, we consider die, trie, tetra. We will consider die methyl to be starting from D and ethyl from E. So this means die methyl will come first and ethyl later. Now let's do the numbers. So, there are two cases possible in this. Its numbering can be done in two ways. This compound can be numbered from left or right. Locant will be same. But we have to give lowest locant to that which comes first alphabetically. Because our complex chain dimethyl ethyl will come first from dimethyl ethyl. So, the fourth locant should go to dimethyl ethyl. So this is the correct numbering. So the name of this compound is 4, 1,1-dimethyl ethyl, 6-ethyl. And because there are 9 carbon in this chain, so it's nonane. So this was a complex chain. We have completed all of its rules using these three examples. Now let's talk about poly function groups. Poly means many, so poly function group means many function groups. Now we will do naming of such compounds, in which 2-3 different types of function groups are present on the same organic compound. So how to do naming in that case? We will follow a priority table for it. The priority table which is at higher level, its priority is higher. And the function group whose priority is higher, we call it primary function group. And the priority of the function group which is low, we consider it as secondary function group. So let's do an example and understand this concept. In this compound, alcohol and carboxylic are both present. We will do priority table later, but now keep in mind that Carboxylic is more priority than Carboxylic and alcohol. So COH is primary function group and alcohol is secondary function group. Primary function group will come in main chain. So this is our main chain. And we will treat secondary function group as side chains and substituents. For secondary function group, we use prefix. Alcohol, for this we use suffix, but here we will not use suffix. Here we will use prefix. Because alcohol is secondary function group. So now just remember this, since alcohol is a secondary functional group, we will use a prefix for it and that prefix is called Hydroxy. And for primary functional group, we use a normal suffix. That means for COH, we will use a normal Oic acid suffix. Nothing different. So first of all, we will name this main chain. Main chain has 5 carbons and 1 COH. So this is called Pentanoic Acid. Now let's do numbering. Numbering obviously we will start with cos because it's a terminating group. So yeh hogay numbering. OH is at 5th position and this time we have to use prefix hydroxy for OH. So we will write 5-hydroxy. Now after prefix we have to write main chain and main chain is our pentanoic acid. So this compound is 5-hydroxy-pentanoic acid. Now let's see priority table. Now, there is a systematic way to learn the priority table. So, let's learn it in a systematic way. The first thing that comes in the priority table is Carboxylic Acid. And after Carboxylic, the priority is Carboxylic derivatives. So which are the carboxylic derivatives? COR, COCL, CONH2. All of these are made from carboxylic acid. That's why it's called carboxylic derivative. So first one is ester, second is acid chloride, third is acetamide. We had already named all of these. We know what suffix we have to use for them. But in this section, we are going to see what prefix we have to use for them. So after this comes function. Function group with triple bonds. So in this list, we have cyanides and isocyanides. So cyanide is written as C triple bond N. Isocyanide is written as N triple bond C. Next comes function groups with double bond. So in this list, we have CHO and CO, aldehyde and ketone. And last is function group with single bond. So in this list, we have OH, SH, NH2, NHR, NR2. Alcohol, thioalcohol. Amine, secondary amine, tertiary amine. So this is how you can remember priority table. First of all, Carboxylic, then Carboxylic derivative, then triple bond groups, then double bond groups, then single bond groups. So what should be their new name as a prefix? For example, we used hydroxy for alcohol. What will we use for these groups? First of all, Carboxylic. For Carboxylic, we will use Carboxy. Next is ester. For this, we will use Alcoxy. Carbonyl. If you divide COR into two parts, then we have OR and CO. OR part is called Alkoxy and CO part is called Carbonyl. Now next is COCl. It is chlorocarbonyl. So how to remember this? There are two parts in this too, Cl and Co. Cl for Chloro and Co for Carbonyl. So we will call it chlorocarbonyl. Now next is CONH2 Acetamide. And for this we use Carbonyl. After this comes cyanide, for this we will use the prefix cyano. It's easy to remember because the functional group is called cyanide. Next is isocyanide, for isocyanide we use the prefix isocino. Next is aldehyde, for aldehyde we use formaldehyde. Next is ketone, for ketone we use oxo or keto. Next is OH, for this we use hydroxy. Next is SH, for SH we use SH. Sulfenyl, NS2, Amine, Amino, NHR, Alkyl Amino, NR2, and Dialkyl Amino. These were the function groups that we can use as a prefix and suffix. But there are some function groups that are always treated as substituents. First is OR, that is Alkoxy. Then comes SR, that is Alkyl. Alkyl, Thiol. Then F, Cl, Br and I. For these we use Fluoro, Chloro, Bromo, Ido. Then comes NO2. For this we use Nitro. And we use a Zido prefix for this one and Diazo prefix for this one. Having it all done, let's do two examples. So in this compound, there are two functional groups Ketone and Carboxylic acid. Priority order according COH lies above CO. That means Carboxylic acid Ketone is our main functional group and ketone is our secondary functional group. So we will use oxo prefix for ketone. Now let's do the numbering. You must have known about numbering. We have to start numbering with carbon because it is terminating group. So let's do the numbering. So this is the numbering. And where did ketone come? Ketone came at third position. So the name is 3-oxo. And because there are 5 carbons in main chain, Carboxylic acid. So it is pentanoic acid. So it is 3-oxo-pentanoic acid. Now second example. Look at this compound. It has total 4 functional groups. So let's write them in order of their priority. First comes CO-NH2, Acid Amide. After that, CO-Ketone. Then OH-Alcohol. And then NH2-Amin. So in priority table, first comes CO-NH2. So it is... This is our primary function group. So for CO and NSTO, we will use normal suffix and that is amide. But for the other three, we will use oxo for CO, hydroxy for OH and amino for NSTO. Now it is time for numbering. So it's simple, we have to do numbering with CONS2 because CONS2 is a terminating group. So let's do the numbering. So OXO got 4th locant, Hydroxy got 3rd locant and Amino got 2nd locant. Now it's time for naming. For naming, just follow the alphabetical order. First comes amino, then hydroxy, and last oxo. So it's 2-amino-3-hydroxy-4-oxo. And our main chain has 5 carbons and acid amide. So for this we'll use pentanamide. So we'll call it 2-amino-3-hydroxy-4-oxo-pentanamide. Now it's time for cyclic compounds. Now it's time for cyclic compound. So let's do cyclic compounds in more details. So first of all we will do the naming of these two basic compounds. Now let's name these two compounds. First of all, this compound is looking like a square. But it is not a square, it is a cyclic compound. Every corner of it represents a carbon. There are total four corners here, which means there are total four carbons here. So for four carbons, we use butane. But because we are using butane, This time, it is a cyclic structure. So, we will call it as cyclo-mutane. The second one is also a cyclic structure. It has 6 carbons and a double bond. So, first we will write cyclo, then hex and then ene. Because here, there is a double bond. So, we will call it as cyclo-hex-ene. So, this was the basic thing. Now, we will do some examples and each example will tell us about a new rule. Look at this compound. This compound has both cyclic ring and open chain. So what will be the name of this compound? The first thing to do is to decide which part is main and which part is side. So for this we will count the number of carbons on cyclic ring and open chain. The one who has more carbon is the principal part. Here on cyclic ring there are 6 carbons and on open chain there are 4 carbons. So obviously the principal part is cyclic ring. And the open chain is the side chain. Since cyclic is the principal part, its name should be like a normal cyclic compound. Cyclic has a total of 6 carbons. So we will write it as cyclohexane. Now it's time for side chain. Our side chain has 4 carbons. So its name is butyl. Now it's time for numbering. Since cyclic is the principal part, we will number on cyclic's carbons. And simply follow the lowest loken tool. So we will follow this. So here we will start numbering with butyl So butyl gets locant 1. So finally we will write this compound as 1 butyl cyclohexane. Now next example. Here cyclic has 6 carbons and open chain has 6 carbons. Both have equal carbons. So in this case, who is considered as the principal chain? In such a case, we give priority to cyclic ring. So same as the last one, this time also cyclic ring is the principal part and open chain is side chain. So this compound also has name as 1 butyl cyclohexane. This will be like the previous example. So it's going to be 1-hexyl-cyclohexane. Now next case. This time, there is less carbon in cyclic and more in open chain. There are 3 carbons in cyclic and 4 carbons in open chain. So in this case, open chain is the principal chain and the cyclic part is the substituent. In normal condition, this cyclic compound is called as cyclopropane. But this time since it is a substituent, so this time we will write it as cyclopropyl. And this time numbering will be on open chain. Because cyclopropyl is at locant 1, so we will write it 1 cyclopropyl. And because there are total 4 carbons in the main chain, so we will call it butane. So, its IUPAC is named as 1 cyclopropyl butane. Next compound, this compound has 1 open chain and 2 cyclic rings. So, in such a case, no matter how big the cyclic ring is, We will consider the open chain as the principal part. In this case, there are only 2 carbons in the open chain and 3 carbons in cyclic. But since cyclic ring is more than 1, in this case, we will consider the open chain as the principal chain and cyclic ring as the substituent. Since cyclic ring has 3 carbons, we will write it as cyclo-propyl. Now it's time for numbering. Here, on the first and second position, there are two cyclopropyls. So, ultimately it will be written as 1,2-dicyclopropyl. And there are two carbons in the open chain, so it's ethane. So, this compound is 1,2-dicyclopropyl ethane. Now next example. Now let's see the power of multiple bonds. This compound has a double bond. Here, cyclic ring also has 3 carbons and open chain also has 3 carbons. In normal case, cyclic ring is considered as the principal part. But in this case, there is a double bond. The part where the double bond is present, it will increase the priority. Even though here, the cyclic is considered the principal part, but because a double bond is placed in the open chain, so we will consider the open chain as the principal part. And the cyclic part as just a substituent. So let's do the numbering. During numbering, double bond is more important than substituent. So we will start numbering from the right side. So this is the correct numbering. Here we will call cyclic ring as cyclopropyl. And because it is in third position, so we will write it as 3-cyclopropyl. There are 3 carbons in open chain and a double bond too. So we will write it as prop-1-ene. So the name of this compound is 3-cyclopropyl-prop-1-ene. Next example, in this case open chain is bigger than cyclic chain. In open chain there are 4 carbons and in cyclic ring there are 3 carbons. But because this time double bond is applied on cyclic ring, so cyclic ring is principal part. Now let's do its numbering. The numbering of this compound will start with double bond. So let's do the numbering. Side chain came on third locand and double bond came on first. And on side chain there are 4 carbons. So it is called 3-butyl. There are three carbons in cyclic ring and a double bond too. So we will write it as cycloprop-1-ene. So the name of this compound is 3-butyl-cycloprop-1-ene. Conclusion is that in cyclic structures, multiple bonds are more important than longest chain. And more important than multiple bonds is the functional group. So let's see a compound which has a functional group. Let's see this example. Open chain has 3 carbons and cyclic ring has 5 carbons. But this time, open chain has a functional group and cyclic ring has a double bond. We know which one is more important. It's functional group. So this time we will consider open chain as a principal chain. Because it has a functional group. Now let's come to numbering. So, we have to do numbering in such a way that the function group gets the lowest lock-end. So let's do the numbering. Now first of all, let's do the naming of the principal part. It has three carbons and one alcohol. So you can write it propanol. In this case, cyclic ring is an interesting part. This cyclic ring will be treated like a complex chain. So, we will use the rules of complex chain in this. So, the first thing is numbering. We have to start numbering from linking side. Because it is a complex chain. So, let's do the numbering. So double bond came on 3rd position. So let's write its name step by step. First of all cyclo, cause it's cyclic compound. There are 5 carbons, so use pent. And on 3rd position there is double bond, so use 3-in. And since it is a side chain, so for this we will use suffix"-ile". So it will be named as cyclo-pent-3-in-ile. And since it is a complex chain, so we will write it in bracket. Aur ye cyclic ring principal chain pe second position pe hai. So this is written as 2-cyclopenthreenyl. And after that write its principal chain propanol. So this compound is 2-cyclopenthreenyl propanol. Functional groups on cyclic ring. I am showing you 6 cyclic rings with functional group. In these 3, functional group is a part of cyclic ring. Alcohol, Ketone, and Nitro. All of them are considered as a part of cyclic ring. But last three with Cyanide, Aldehyde, Carboxylic, they are not considered part of cyclic ring. Because their carbons are outside of cyclic ring. So what difference will it make in naming? We will not use Nitrile for Cyanide, Al for Aldehyde, and Oic Acid for Carboxylic Acid. We will use new suffix for them. But the first category will be named in a normal way. So the first one is called Cyclobutanol. For alcohol we are using the old one here and we use the old one anyway. Next one is called Cyclopentanol. Now here we are using the own for ketone and we use the own anyway. Last one is Nitrocyclobutan. Nitro is used as a prefix and here also we are using it as a prefix. And the thing changed. Now let's move to the second category. We need new suffix for them. So let's see this list. Ye hai inke new suffix. And along with it, there is a list of their prefixes. The prefix hasn't changed at all, but the suffix has changed. So let's understand it by implementing. First example, it has three carbons, a cyclic structure and a cyanide group. And for this, we will use a new suffix, Carbonitrile. So the name of this compound will be cyclopropane carbonitrile. In the next one, there are five carbons, a cyclic structure. and aldehyde group. For aldehyde, new suffix is carbeldehyde. So its name should be cyclopentane carbeldehyde. Last one is cyclic structure. It has 6 carbons and carboxylic acid. For carboxylic, new suffix is carboxylic acid. So the name of this compound is cyclohexane carboxylic acid. This is new suffix. You have to use it when main function group, main function in the main ring. Only then you have to use this suffix. Now look at this compound. It has ketone, carboxylic acid and aldehyde. According to priority, COH comes first, then CHO and then CO. So COOH, carboxylic acid, is the main function group and the other two are secondary. So here we will use prefix for aldehyde and ketone. For aldehyde, the prefix is formyl and for ketone, oxo. As you can see, prefix for aldehyde is formyl and for ketone is formyl. There is no difference between these two. We normally use oxo and formyl for these and here too. So here we have total 6 carbon and along with that we have carboxylic acid. So for this we will use cyclohexane carboxylic acid. Now it's time for numbering. Let's start numbering from carbon linked with CuH. Now we have two options. Either we do numbering clockwise or anticlockwise. If you do its numbering clockwise, you will get 2 for mile, 6 oxo. And if you do its numbering anti-clockwise, you will get 2 oxo, 6 for mile. So in both cases, the locants are the same, 2,6. But we have to choose one of these two. In this case, we will see which one comes first alphabetically. From for mile and oxo, for mile comes first, so second locant should go to for mile, and 6 should go to oxo. So the first numbering... is correct. So write it before main chain's name. So the name of this compound is 2-formyl-6-oxo-cyclohexane-carboxylic acid. Aromatic compound. So the first aromatic compound is benzene. So this is benzene. Benzene is a cyclic structure in which double bonds are alternately attached. And these double bonds continuously change their position. You can draw it like this too. If you expand this structure. It will look like this. Its naming is like a cyclic compound. I am not going to go into specifics. But you will write it as cyclohex-1,3,5-triene. But you will notice that we mostly use benzene for this compound. We don't use cyclohex-1,3,5-triene. Now let's move forward. Now we are going to name these types of compounds. These are called benzene derivatives. Subsidized. First is methyl on benzene. This is called methylbenzene. Another name for this compound is toluene. Benzene with two methyl. There are three possibilities in this compound. Methyl groups can be attached together. One carbon can be attached separately. Or they can be attached completely opposite to each other. So first of all, do the numbering of these three. So this is the numbering. Now in this compound, first we have to write side chains and then benzene. So in the first one, there are two methyl groups in the first and second position. So it will be called 1,2-dimethyl. Now write benzene. So it's 1,2-dimethylbenzene. Similarly, we will name the second one. It will be called 1,3-dimethylbenzene. And the third one will be called 1,4-dimethylbenzene. When two side chains are adjacent to each other like this, then we call it ortho positioning. When side chains lies after a gap like this, we call it meta. And when side chains are on totally opposite directions like this, we call it para. We also call dimethylbenzene xylene. In the first one, the side chain is ortho-positioning. So it's ortho-xylene. Similarly, the second one is meta-xylene. And the third one is para-xylene. Next one, what will we call benzene if it becomes a substituent? In such a case, we will call it phenyl, not benzene. So this is phenyl. Now, look at these three structures. We are going to use them a lot. This is methyl benzene. with one linking site on methyl. We call this structure as Benzyl. Now comes this structure, which has two linking sites on methyl. This structure is called as Benzyl. And this one has three linking sites. This is called as Benzo. Now let's use them. Look at these three structures. Here are Benzyl, Benzyl and Benzo. And their linking sites are filled with chlorides. So the first one is called Benzyl Chloride. Next one is called benzal dichloride and the third one is called benzo trichloride so it's very simple now let's do more benzene derivatives so this one is benzene with alcohol this is called phenol so this one is benzene with methoxy and this one is called methoxybenzene and its second popular name is anisole now comes the combination of benzene and aldehyde this is called benzaldehyde This one with COCH3, we call it Acetophenone. So basically what is this? This is Ketone with Methyl on one side and Benzene on other. Methyl and Ketone will make the main chain and Benzene will make the substituent. So we will write the part with Benzene as Phenyl. And next is CH3CO part. This is called Ethanone. So we will name it as 1-Phenyl-Ethane-1-O. Next compound, it's obvious, it's nitro benzene. This one with amine group 1 benzene, it's called aniline. Benzene with COH, it's benzoic acid. Benzene with acid chloride, it's called benzoyl chloride. We use oil chloride for acid chloride. So that's why it's benzoyl chloride. Benzene with CO2, amide group. So it's called benzenamide. Benzene with SO3H, sulfonic acid. So it's called benzene sulfonic acid. Now the last one, benzene with cyanide. So it's called benzene carbonitride. Now we will use these benzene derivatives in some examples and then IUPAC nomenclature is completely done. First example. In this example, nitro and carboxylic are used on benzene. Nitro is a substituent here and carboxylic is a substituent here. So, here we have main function group. So, this is principal part of this compound. So, we will write substituent first then principal part. So, Benzene plus Carboxylic, it's called Benzoic Acid. And because Nitro is substituent, so we will write Nitro prefix for it. So, it's Nitro Benzoic Acid. And for Nitro position, we will do numbering. So, we have to start numbering with that carbon on which Carboxylic is applied. So, let's do the numbering. Nitro is in second position. So the name of this compound is 2-Nitro-benzoic acid. Now let's do its naming. It has three groups. Aldehyde, Alkoxy and Alcohol. Alkoxy will be the substituent. But which will be the main one between aldehyde and alcohol? Aldehyde is grouped with double bond. And alcohol is grouped with single bond. According to priority table, aldehyde will come first. And alcohol will come second. So our principal part was benzene with aldehyde. So benzene plus aldehyde is called benzaldehyde. Now we have alcohol and alkoxy. And for these we will use prefix. For alkoxy we will use methoxy and for alcohol we will use hydroxy. So let's find out their locants. For numbering we will follow lowest locant rule. So do numbering in such a way that both substituents are on lowest locant. So here we should do numbering. block wise. So, methoxy came on 3rd and hydroxy came on 4th. Now, write them in alphabetic order. So, first of all we will write 4-hydroxy and then methoxy and after that we will write benzaldehyde. Now, one more example. This compound has two parts. One part is benzene and the other part is open chain. Here, a functional group is attached on open chain that is bromine. So, because of this open chain became main chain and benzene became 20 Now it's time for numbering. For numbering, we will just follow the lowest locant rule. If we do left to right numbering, then we will get lowest locant. So this is the correct numbering. So first of all, let's write substituents. Because benzene is a substituent, so we will use phenyl for it. Here bromine is a functional group, but for this we use a prefix and that is bromo. So for this we will write 2-bromo-1-phenyl. And because there are 4 carbons in the main chain, so we will use butane. So this compound is 2-bromo-1-phenyl-butane. Now the last compound. Here one side is benzene. and the other side is cyclohexane. Which will be the main and which will be the substituent of benzene and cyclohexane? In this case, we will consider benzene as the main and cyclohexane as the substituent of cyclohexane. So, we will call this cyclohexyl and benzene as normal benzene. So, its name will be 1-cyclohexyl-benzene. If you have completed these school tuitions, then you must be aware that it takes at least 2-3 weeks to complete this chapter. But we have completed this chapter within 1.5 hours. So, congratulations! You have completed IUPSC Nomenclature in just 1.5 hours. Now, your job is to use these rules and practice more and more questions. So, this was IUPSC Naming and you are watching IUPSC. Don't forget to like, subscribe and share.