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let's do a few more examples of seeing if either an atom or an entire molecule is chiral so here I have a molecule let's see if we can identify any chiral centers or any chiral atoms or asymmetric carbons all words for the same thing although I guess you could have chiral centers that aren't necessarily carbon but it tends to be carbon most of the time especially in an organic chemistry class so if we look here the one that kind of jumps out this carbon right here is bonded to three hydrogen's and another carbon so this is obviously not going to be a chiral Center it's bonded to three of the same group these three guys are all bonded to two hydrogen's each so they're all bonded to two of the same group so they can't be chiral centers this carbon right here is bonded to three hydrogen's once again three of the same group not going to be a chiral Center this one looks interesting looks like it could be a good candidate for a chiral Center or chiral carbon or an asymmetric carbon over here on the left it's bonded to a methyl group so this is a methyl group and here on the right it's bonded to a butyl group here on the right it is bonded to a butyl group it is bonded to a butyl group over here it's bonded to an O and then over here it's bonded to an H so this is definitely a chiral carbon we could put a little asterisks here that's how they often denote that this is a chiral carbon if this doesn't make sense to you cuz you might say hey Sal look this carbon is bonded to two other carbons isn't that the same thing but the point here is that we're not looking at what atoms it's directly bonded to we're looking at the groups that it's bonded to in this case this hydrogen is a group and an atom over here it's an entire group its entire butyl group we have four carbons here we only have one over here another way to think about it we could have drawn this we could have drawn this molecule like this we could have had a carbon in the center and maybe this methyl group is popping out like this so maybe this methyl group is popping out like this you have your ch3 and then you would have this hydrogen coming out maybe in the plane and then behind it you would have the butyl group so kind of the back leg of the tripod you'd have a butyl and what is that that's c4h9 right that's six-plus c4h9 so it's c4h9 in the back and then above it you have your Oh H above it in a different color you have your H and when you look at it like this it looks just like the other chiral carbons that we had identified in previous and actually the last video it looks very similar to something like this and when you take its mirror image this and this is the same molecule here I kind of made it a little bit more 3-dimensional but if you take the mirror image of either one you're going to find that no matter how you take how you try to rotate it or shift it you won't be able to superimpose it on its mirror image for the same reasons as the other ones that I challenge you to if you can if you can so these so this is a chiral carbon this is a this is a chiral chiral chiral center we could say or we could even call it a a asymmetric carbon it could be considered a stereo Center or a stereo Zdenek genic Center all all of those are valid things to call this carbon right there and this is also a chiral molecule this is also a chiral molecule chiral molecule now let's look at this blue example right here and just as if we wanted to name it just so we get a little bit of review we could start it this fluorine right there 1 2 3 4 5 5 this is what this is 1 comma 3 1 comma 3 dye dye fluoro cyclo cyclopentane so that was a nice review of naming but let's think about whether we have any chiral centers here and whether the molecule as a whole is chiral so the immediate ones that we can kind of dismiss and actually let me let me get rid of numbering here just because I don't want you to think that they're somehow three hydrogen's there this is the number that was the number three hydrogen number one car not number three carbon number two carbon so on and so forth but let me get rid of them now that we've now that we've named the molecule that want to confuse how many hydrogen's we have at any of these points so let's look at the carbons well we could immediately dismiss that carbon that carbon in that carbon because each of those are bonded to two hydrogen's if we wanted to break it out at what they would look like this so they're bonded to carbons carbons and then they're bonded to hydrogen's now these might be different groups these might be different types of alkane groups that it's bonded to so that doesn't necessarily throw it out of the running but these two the two hydrogens that it's bonded to are definitely the same atom the same group we have an axis of symmetry through through through that atom so it cannot be a stereogenic Center it cannot be an asymmetric carbon it cannot be a chiral Center or a chiral atom so we can knock those guys out of the running but this guy and that guy seemed pretty interesting because if we were to break it out a little bit you could break it out like that and break it out like that instead of writing a CH actually showed the bond to the hydrogen and this guy is bonded to one hydrogen one fluorine and then if we were to work our way around around the cycle and these cyclical these these cyclic molecules are a little bit it's sometimes a little tricky to identify whether you're whether you're bonded to a the same group or different groups but actually let me not make it too messy while we try to figure this out to figure out whether it's bonded the same group let's kind of take a walk around the the cycle around the the cyclopentane ring if we go this way if we go on a counter we did a different color if we go in a counterclockwise direction from the carbon in question we're going to hit a ch2 and then we're going to hit a CH so we're gonna hit a ch2 then we're gonna hit a CH if we go this way we're gonna hit a ch2 and then were gonna hit another ch2 so this guy is fundamentally whether this bond is bonded to a different group then that bond up there is and it's also bonded to a hydrogen also bonded to a fluorine so this is bonded to four different groups so this is a chiral carbon so that is a chiral Center chiral Center now the exact same argument can be made for this carbon right here you can make that exact same argument that look if you were to walk if you were to walk counterclockwise from this or if you were to write counterclockwise you would hit a ch2 than a ch2 if you were to go clockwise you just ch2 then a CH which happens to be connected to a fluorine so you're actually going to see something you're actually going to see something different depending whether you're going down that into that group or into that group and then it's also bonded to a hydrogen and a fluorine for different groups this is also a chiral Center another way to think about it and it's actually interesting to compare it to this molecule up here which was not chiral and did not have a chiral center this molecule up here and let me draw a little different to make it a little bit more clear let me draw it a little bit different so this one I could draw it like I can draw it like this I'm just making if you have the chlorine like that over here we we thought about this as a potential chiral Center and it's kind of playing the same role as in that example down here as in this example of this carbon down here but you see over here this is not a chiral Center because there's actually an axis symmetry for this molecule that goes through that carbon so you can actually just draw an axis of symmetry that goes exactly through that carbon it's not you know the way I drew it it's not completely neat but you can see that that is the reflection of that if I were to draw the bonds actually a little bit more symmetric over here if we try to do the exact same thing if we try to draw an axis of symmetry over here we try it on accident we could make that bond to the fluorine go through our axis of symmetry we'll see that that still is not this is still not the reflection of this because we have a fluorine up here we don't have a fluorine over here and we could do the same thing with this end if you try to do an axis of symmetry fluorine up there no fluorine over here so this each of these are definitely chiral centers while this carbon up here this carbon up here was not a chiral center now the next question is well this thing's got two chiral centers two chiral carbons it's probably a car a chiral molecule everything else we've seen so far if you've had a chiral Center you had a chiral molecule but let's take its mirror image let's take its mirror image in to take its mirror image let me clear out some real estate over here so let me clear out this let me clear it out so what's the mirror image going to look like so we have let me draw first the mirror let me first draw the mirror so the mirror image you're gonna have a fluorine over there then you're gonna bond to a carbon which is also bonded to a hydrogen and that's going to bond to a ch2 that's going to bond to a CH that's the mirror image of that which bonds to a fluorine that's the mirror image of that and then you go down this is the mirror image of ch2 here this is the mirror image of this and you connect them now these are mirror images of each other but they are also the exact same molecule I could just literally move this guy over to the right and it would be superimposed they are exactly the same so even though we have two chiral atoms two chiral carbons the molecule as a whole is not chiral so it's not chiral it is a non it is a non chiral molecule