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Current time:0:00Total duration:6:50

Video transcript

we've already seen alcohols in many of these videos but I thought it was about time that I actually made a video on alcohols all on alcohols now alcohols is the general term for any molecule that fits the pattern some type of functional group or chain of carbons o H and they use the letter R and I've used it before R stands for radical and I want you to confuse this R with free radical means completely different things are in this form really just means a functional group or a chain of carbons here it doesn't mean a free radical this just means it could be just you know something attached to this o H right there now another point of clarification do not think that anything that fits this pattern is drinkable do not associate it with the traditional alcohol that you may or may not have been exposed to traditional drinking alcohol traditional drinking alcohol drinking alcohol is actually ethanol alcohol is actually let me write out the molecular formula ch3 ch2 and then Oh H this is what is inside of wine and beer and hard liquor or whatever you might want you do not want to drink and maybe you might not actually want to drink this either but you definitely do not want to drink something like methanol it might kill you so you do not want to do something like this you do not want to ingest that might kill or blind you this might do it in a more indirect way so I want to get that out of the way and just so we get kind of a little bit more comfortable with alcohols and we've seen them involved in other reactions we've seen hydroxides acts as nucleophiles and sn2 substitution reactions create alcohols but what I want to do is just learn to you know get comfortable and really make sure we know how to name these things so let's just name these molecules that I drew right before I pressed record right over here so over here like everything else we always want to defy the longest carbon chain we have 1 2 3 4 5 carbons so it's going to be pent so it's going to be tenth and there's no there's no double bonds so it's a pentane so I'll just write pent pentane right there and we're not going to just write a pentane because actually the fact that makes it's an alcohol that takes precedence over the fact that it is an alkane so it actually the the suffix of the word will involve the alcohol part so it is Penta null so let me I'll do that the Penton all that tells us that it's an alcohol and to know where the O H is grouped we'll start numbering closest to the O H so 1 2 3 4 5 so this sometimes it'll be called 2 Penton all and this is pretty clear because we only have one group here only one o H so we know that that is what the 2 applies to but a lot of times if people want to be a little bit more particular they might write pent pen ton pen ton to all-to-all and this way is more useful especially if you have multiple functional groups so you know exactly where they sit this one is harder to say to Penton all is pretty straightforward now let's try to name this this beast right over here so we have a couple of things going on this is an alkyne it is an alkyne we have a triple bond it's an alkyne we have to bromo groups here and it's also an alcohol and alcohol takes precedence on all of them so we want to start numbering closest to the alcohol so we want to start numbering from this end of the carbon chain and we have 1 2 3 4 5 6 7 8 carbons so this is going to be this is an acht this is we want to call it an octane but because we have an alcohol there we want to call this an octane octet me let me make it very clear so we acht tells us that we have eight carbons now we have to specify where that triple bond is the triple bond is on the 5 carbon you always specify the lower number on between of the carbons on that triple bond so it is acht 5 5 EIN that tells us that's where the triple bond is and then we have the the OAH on the 4 carbon so 4 4 for all and now we have these two bromo groups here on the seven carbon so it's seven it's seven seven die bromo die bromo acht five nine for all and this would all be one word let me can make sure that you realize that this should be connected I just ran out of space so that's probably about as messy of a single after name but just showing you that these things can be named now let's think about this one over here in green so we have one two three four five six carbons so it's going to be a hex and it's actually ended all single bonds so it's a hexane it's a cyclohexane but then of course the hydroxide or the the hydroxy group I should call it takes dominance so it's it's a it's a hexanol so this is a cyclo cyclo hex an all and once again once again that comes from the Oh H right there and you don't have to number it because no matter what carbon it's on it's on the same one if you had more than one of these O age groups then we would have to worry about numbering them now let's finally let's just do this one right over here so once again what is our carbon chain we have one two three carbons and we have the hydroxy group attached to the one and the three carbon so this is going to be this is pro is our prefix it is an alkane so we would call this we would call this and there's a couple of ways to do this we could call this one comma three propane Pro pin' dial actually I don't have to put a dash there Pro pinned dial and over here we would add the e because we have the D right there so it's pro pinned dial if it wasn't dial it would be pro pin' all you wouldn't have the e d and the I there so this was specified we're at the 1 and the 3 carbons we have the hydroxy group or this could also be written as propun propane propane 1 3 dial and once again the die is telling us that we have two of the hydroxy groups attached to this thing but either of these things are ways that you would see this molecule named