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Video transcript

all the functional groups in this video contain a carbon oxygen double bond and we call a carbon oxygen double bond a carbonyl so here you can see a carbon oxygen double bond in this functional group and here's another one in this functional group and here's another one down here for the first functional group this is called an aldehyde so an aldehyde has an R group on one side of the carbonyl and a hydrogen on the other side of the carbonyl as an example let's look at this compound so here is our carbonyl our carbon oxygen double bond and then on this side we have a hydrogen directly bonded to this carbonyl carbon on the left side we have this R group so the carbonyl carbon gets a number one it gets the lowest number possible and then this carbon would get a number two this carbon would get a number three and this carbon would get a number four so we have a four-carbon aldehyde so how do we name a four-carbon aldehyde well a four-carbon alkane we know is butane so 1 2 3 & 4 we know that this compound is called butane and aldehyde has an Al ending so if you see an Al ending that indicates the presence of an aldehyde so we're going to lose the e from butane and add on Al so the name of this molecule becomes butan al let me write that out here so this is butane ow next let's look at a ketone so a ketone has an R group on one side of the carbonyl and an R group on the other side of the carbonyl so for our ketone example let's look at this compound we're going to number to give our carbonyl the lowest number possible so we're going to start numbering from the left side of our compound so this is get carbon number 1 the carbonyl carbon would be carbon number 2 this is carbon number 3 this is carbon number 4 and this is carbon number 5 so we have five carbon ketone a 5 carbon alkane let me go ahead and draw out a 5 carbon alkane here this would be called pentane so that would be pentane a ketone has an O n e ending so own indicates the presence of a ketone so we're going to lose the e from pentane and add own so this would be pentanone so this is pentanone we also need to indicate the position of the carbonyls the carbonyl is at carbon 2 so we need to write two pentanone and that's because we could draw we could draw another another molecule that's pentanone but this could have the carbonyl at carbon 3 so let me go and write that in here 1 2 3 so this compound would be 3 pentanone and 3 pens known and two pens known are different molecules so that's why we need to indicate the position of the carbonyl for the aldehyde up here we didn't need to indicate that the aldehyde is at carbon 1 that's the only place that it could possibly be notice that an aldehyde has has this hydrogen right directly bonded to the carbonyl carbon whereas a ketone has if we look at the carbonyl group right here we have a carbon on one side right a ch3 on one side in this case and we have a carbon on this side directly bonded to that carbon eel carbon so that's the difference between an aldehyde in the ketone and a lot of students have a hard time telling the difference between an aldehyde and a ketone look for this hydrogen directly bonded to the carbonyl carbon and that's an aldehyde next we have a carboxylic acid so a carboxylic acid has an R group on one side of the carbonyl and an O H on the other side some students think that this is an alcohol at first but this is not an alcohol this Oh H is right next to this carbonyl and that changes the properties carboxylic acids have different properties from alcohols so for an example of a carboxylic acid over here on the right we know that our carbonyl carbon gets number 1 so that's carbon number 1 this is carbon number 2 carbon number 3 and carbon number 4 so a four carbon carboxylic acid so a 4 carbon alkane appear was butane so we're going to have acid as our ending so it would be butanoic acid for the name this compound so there's just one of the names so one of the names for this molecule would be butanoic acid alright probably the most famous car box out probably the most famous carboxylic acid is a two carbon carboxylic acid so I can just draw it like this really quickly and this is called a seat ik acid so vinegar is just a a dilute solution of acetic acid in water alright our next our next functional group is called an ACL halide or we could also call it an acid halide and you're pretty much talking about acid chlorides in organic chemistry and so here is our carbon oxygen double bond and then on this side we have an R group and the right side we have a chlorine so a CL halides come from carboxylic acids so this is an example of a carboxylic acid derivative an example of an acyl halide on the right here we have we have our carbonyl and then we have our halogen and the reason I like to call an acyl halide is this right here on the left this is an acyl group and on the right we have our halogen so this would be acetyl chloride is one of the names for this but you can also call them an acid halide these are carboxylic acid derivatives so some some professors prefer one term and some professors prefer the other term our next functional group is an acid anhydride so here is our carbonyl here's the R group and instead of a chlorine like we had up here we have all of this over here on the right so this is an acid anhydride or just an anhydride this is also a carboxylic acid derivative you can form an acid anhydride from a carboxylic acid and for the example over here on the right we have acetic anhydride next functional group is called an ester so an ester is another carboxylic acid derivative so a carboxylic acid had a hydrogen it's in this position but now we have an R group so we have our carbonyl we have an O R and then we have an on the left so that's an ester and here's an example of an ester over here so we have an ethyl group instead of a hydrogen so for acetic acid let me go ahead and draw acetic acid again acetic acid had a hydrogen right here and now we have an ethyl group so instantly we know we're talking about an ester we're not talking about a carboxylic acid if you wanted to name this ester you have this ethyl group so that would be ethyl and then this part would be acetate so ethyl acetate would be the name now for the names of all these you're going to get to them later in the course so it's probably not that important to name these compounds but it's good to start hearing these things now and finally our last functional group is called an amide at least that's what I call it but there are several different ways to pronounce this functional group the dictionary says at least my dictionary says amides are a m''d are the two preferred ways to pronounce this you'll probably hear amid as as one of the most common ways to pronounce this a lot of professors say amid and some professors get pretty upset if you if you don't pronounce this the way that they want I've heard many more ways to pronounce this functional group - like a mite and all kinds of things use whatever pronunciation your professor wants that's always the way to do things now we have a carbonyl I notice we have a nitrogen right next to the carbonyl carbon so a nitrogen directly bonded to the carbonyl carbon lone pair of electrons on the nitrogen so that's an amide functional group or an amide functional group so these ours hydrogen's right you could be talking about hydrogen's or you could be talking about alkyl groups so there's lots of different examples of amides or amid on the right is an example so our carbonyl carbon gets a number one so this would be one this would be number two this would be number three this would be a number four so a four carbon amides would be butane amides let me go and write that down here so this would be beaut an amide or a beaut an amid depending on how you prefer to pronounce this functional group