Male Speaker: Now we are going to take some of these organic molecules. It could be aliphatics or aromatics. And we are going to put on to them some derivative groups or derive some other types of groups. Now, the major ones that we are going to concentrate on because now in Alberta chemistry and chemistry 30 -- chemistry, we concentrate on three types of hydrocarbon derivatives. We do alcohols, carboxylic acids and esters. Oh well, there is some other ones that I will mention a little bit later.
At first Alcohols and how to name them. Well, they end in ol. So, if you have that group right there, which is a meth and it used to be methane well, we have just put an alcohol group on it OH. By the way that OH is going to make virtually all of these alcohols polar in nature; that means now when they are polar, but when one molecule of an OH type of bond here comes together with another molecule of the same type, you are going to get hydrogen bonding as the intermolecular force. What that means is that alcohols are going to have very strong intermolecular bonding. Which means, they are going to have very high boiling and melting points.
Remember, methane has a boiling point of around negative of 184 degree celsius. How much higher is it when you make methanol? By the way, that's the name. So, it's methane, drop the e add ol then it's methanol. That -- boils at around, I think 76 or 74 probably -- degree celsius. So, we've got an increase of almost a 100 degrees in boiling point and that's how much stronger the intermolecular forces when you have one of these molecules attracted to another. What's the name going to be if we do this? Well, methanol was wood alcohol, nasty stuff; you would never want to drink that stuff. But this, that's okay, because that's not methanol at all. This is going to be ethanol and that is green alcohol. that's the stuff that you can drink, not too excess.
Now, over here, you look at this one and you say well, I got it, no problem, that's propanol. Well, yeah you are right. Exactly. That OH group could be at the first carbon, instead and that would be a propanol proper, a proper propanol. But, what's this one when the OH is secondarily attached where you have hydrogen appear but the rest over here on either side. When you attach an OH group into the middle of the chain, you got to tell where it is. So, this is going to be, now you could say, well it's ols at the two. So, really it's going to be propane now, because we are going to, because we are going to follow this with a valve at the ol at the end. We have to put e at the end. So, it's propane and it's going to be two ol. Sounds kind of funny, but that's what it is because the ol is at the two of that propane molecule.
Okay, what's this? So, what we've got here is we got an alcohol group here at the longest continuous chain. that's what we have to find out. One, two, three, four. That's chlorine not a carbon. So, it's four here. One, two, three, four, five there, tricky. So that means then that the longest continuous chain is here, that means this is a branch, that's like a branch two isn't it and so is that. So, now we've got to name everything that's on this what, on this pentane. So, it's going to be, but it's not a pentane. Wait, because it has got an OH group on it.
So what's up, pentanol. Where is the ol, it's at the, now wait. If you get a one, two, three, four, five, so it's going to be at the three or it's going to be at the three, going this way. So it doesn't matter. But since the chlorine here, which is the next most important kind of branch, is at this end, I would start with that end right over there. It doesn't necessarily make a difference, but that's the best kind of start.
So, we are going to go one, two, three. So, we are going to say that that's a pentane three ol, so how you name it, where now, what's the lowest complexity branch that we have, the methyl, what's it on? It's also on the three. So, it's a 3-methyl- and what's over here on that one, that's the chlorine. So, it's 1-chloropentane-3-ol. that's what the name of that one would be right there. Hopefully that's kind of integrating everything you need to know there about the alcohols. By the way, that's called a primary alcohol because, the OH group is at the end of the molecule. This is called a secondary alcohol because, this right here and this right here are carbon pieces that will call the rest. Sometimes, we'll see them abbreviated Rs and there is hydrogen appear. that's called the secondary alcohol.
When you have, right here attached to this carbon here and for this OH here, you have a rest here, the rest over here, and then not hydrogen on top of the rest here where you got this carbon attached to a bunch of other carbons, that's called a tertiary alcohol.
Transcription by:
Scribe4you Transcription Services