in this video we're going to focus on naming benzene derivatives so let's start with the mono substituted benzene derivatives so how can we name this molecule let's say if we have a benzene ring with an no2 group attached to it what's the name of this molecule the no2 group is called nitro and so combined this is called nitro benzene by the way i recommend having a piece of paper or something to write these names down because these parent names you need to commit them to memory now what about the next one let's say if we have a benzene ring with an o h group what do you think the name is called the name is called phenol that's the common name for this and for this example we're going to have a benzene ring with an och3 group so basically this is an ether the parent name that you want to be familiar with is anasol so that's the name for that molecule next up we're going to have a benzene ring with an nh2 group and so if you see this this is called aniline now this one i'm sure you've seen before let's say if we have a benzene ring with a carboxylic acid so this is called benzoic acid now sometimes you may see it like this too so you may see the cooh group and so it's the same this is also benzoic acid now let's move on to our next example what is the name of this molecule what's the parent name now we can also write it like this too so instead of cho it's going to be c with a double bond o and the hydrogen attached to it so we have a benzene ring and an aldehyde functional group so this is going to be called instead of benzene it's benzaldehyde now what is the common name for this molecule let's say if we have a benzene ring and a carbon-carbon double bond attached to it common name is styrene this is also called veno benzene because this is a vinyl group now what if we have a ketone next to a benzene ring like this one this is called acetophenone when you hear the word aceto think of two carbons this is the acetyl group and then when you hear the word phenol phenol has to do with a benzene ring with six carbons and the own tells you we're dealing with a ketone now what if we have a halogen attached to a benzene ring so let's say if we have a chlorine atom compared to a bromine atom how can we name these two benzene derivatives so for the molecule on the left this is called chloro benzene and for the one on the right you can guess what it is that's going to be called bromo benzene now what if we have an ethyl group attached to a benzene ring what's the name for this molecule now this one is pretty straightforward this is simply called ethyl benzene that's it for this example now what if we have a methyl group attached to let's say a benzene ring so what's the name of this one can we say that it's methyl benzene that would make sense but this one has a common name that you need to know and it's called toluene you'll see that one a lot so make sure you know this common name next up we have a benzene ring with an amide functional group so what's the name for this molecule so benzene plus an amide this is called benzamide now what if we have a benzene ring with a nitrile functional group what's the name for this molecule so this one is simply called benzo nitrile now what about having a benzene ring and a ch2 group followed by a chlorine atom what's the name for this molecule so this is a phenyl group if it's just the benzene ring but the phenyl group plus this extra carbon which totals seven carbons that's called benzyl and so this is called benzyl chloride so remember a phenyl group has six carbons a benzoyl group has seven carbons it has the benzene ring plus this additional carbon now what about this one how can we name this molecule so here we have an isopropyl group and so we can call this isopropyl benzene it also has another name the common name is cumin so if you see cumin it's not cumin butter cumin it's isopropyl benzene now let's move on to our next example so here we have a tert butyl group attached to a benzene ring and so this is going to be called tert butyl benzene now what if we have a benzene ring attached to a sulfur atom that has two double bonded oxygen atoms attached to it and an oh group so if you see this group this is called a sulfonic acid combined this is benzene sulfonic acid kind of like a carbo like a carboxylic acid but instead of that it's a sulfonic acid now let's move on to naming disubstituted benzene derivatives so we saw that if we have one methyl group it's called toluene what if we have two methyl groups attached to a benzene ring how is the name going to be different if you have two benzene i mean two methyl groups rather attached to a benzene ring it's going to be called a xylene now this specifically is known as ortho xylene it's also called one two dimethyl benzene so let's call this carbon one this will be number two three and four so with respect to the first methyl group the second method group is at the ortho position ortho is one two meta is one three para is one four now what about this example what is the name of this molecule go ahead and try it so this is still going to be xylene but instead of one two it's one three so we can call it one three dimethylbenzene or we know that one three is the same as meta so we could say this is meta xylene you could write it as m xylene or you can actually write out meta xylene so both ways are acceptable so what do you think the name for this compound is going to be so let's call this carbon one two three four so we can call it one comma four dimethyl benzene or we know that 1 4 is the same as para and so we can call it para xylene or we could just say p dash xylene now let's move on to our next example so now we have two different groups attached to a benzene ring so how can we name this compound well first we need to identify the parent name we know that a benzene ring plus a methyl group is called toluene and so that's going to be the parent name therefore we're going to count the methyl group is going to be carbon 1 because it's part of the parent name so therefore we're going to call this 2 bromo toluene or we could say ortho bromo toluene you can use ortho meta and para for any time you have a disubstituted benzene derivative that's when you have only two groups attached to it so let's try another example so let's say we have a cho group and a cl go ahead and name this benzene derivative so a benzene ring with a cho group that's called benzaldehyde so that's the parent name which means that the aldehyde functional group is on carbon one so we can call this three chloro benzaldehyde or we could say it's metachlorobenzaldine because meta corresponds to the 1 3 positions now let's try another example so let's say we have an och3 group and at the same time we have an no2 group so what is the name of this aromatic compound so the no2 group is called nitro and the benzene ring with an och3 group is called anasal so the parent name is going to be anasal and the nitro group is on carbon 2. so we can call this 2 nitroanisol or ortho nitro anisol now let's move on to tri-substituted benzene derivatives so go ahead and name the molecule so the parent name is going to be phenol because that's the benzene ring with the oh group it doesn't make sense to use nitrobenzene as the parent name especially when there's two of them so we need to count this like this in a clockwise direction so that we can get the lowest numbers so this is going to be called two comma four dinitro because we have two of them on carbons two and four and then phenol now for our next example we're going to have a carboxylic acid a bromine atom and a nitro group attached to the benzene ring so feel free to pause the video and try this example so let's start with the parent name the parent name is going to include the benzene ring and the carboxylic acid so combined we know that to be benzoic acid which means this is carbon 1. now how should we count it in a clockwise direction or in a counterclockwise direction so if we try the counterclockwise direction notice that the bromine atom is on carbon 3 and the nitro group is on carbon 6 but if we count it clockwise the nitros on carbon 2 the bromine is on carbon 5 and so 2 is less than 3 therefore we're going to count it in the clockwise direction now we need to put it in alphabetical order so bromo comes before nitro so it's going to be 5 dash bromo dash 2 dash nitro benzoic acid and so that's how we can name this molecule let's try one more example and so for this example we're going to have a bromine atom a nitro group and at the same time a chlorine atom so what do you think the name of this aromatic compound will be and how should we count it well if we count it this way one two three four so the numbers will be one three four if we count it this way we will get lower numbers one two four instead of one three four and we don't want to start with nitro group because if we count it this way this is going to be 1 2 5 and so we don't want that or if we count it this way it's going to be 1 3 6 which is even worse so this is the best option so this is going to be one two three four now we have a four bromo we have a one chloro and a two nitro so we need to put the substituents in alphabetical order so it's going to be 4 bromo and then 1 chloro b comes c4c and then dash 2 dash nitro benzene and so that's how we can name this particular aromatic compound and so that's it for this video now you know how to name benzene derivatives thanks for watching you