[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.00,0:00:00.43,Default,,0000,0000,0000,,
Dialogue: 0,0:00:00.43,0:00:03.01,Default,,0000,0000,0000,,In this video, we're going to\Nlook at pairs of molecules and
Dialogue: 0,0:00:03.01,0:00:05.91,Default,,0000,0000,0000,,see if they relate to each other\Nin any obvious way or
Dialogue: 0,0:00:05.91,0:00:07.82,Default,,0000,0000,0000,,maybe less than obvious way.
Dialogue: 0,0:00:07.82,0:00:10.84,Default,,0000,0000,0000,,So these first two right here,\Nthey actually look like a
Dialogue: 0,0:00:10.84,0:00:12.26,Default,,0000,0000,0000,,completely different\Nmolecules.
Dialogue: 0,0:00:12.26,0:00:14.11,Default,,0000,0000,0000,,So your gut impulse might\Nbe to say that these are
Dialogue: 0,0:00:14.11,0:00:15.84,Default,,0000,0000,0000,,completely different\Nmolecules.
Dialogue: 0,0:00:15.84,0:00:18.87,Default,,0000,0000,0000,,And it wouldn't be completely\Noff, but we look a little bit
Dialogue: 0,0:00:18.87,0:00:22.89,Default,,0000,0000,0000,,closer, you see that this guy\Non the left has one, two,
Dialogue: 0,0:00:22.89,0:00:26.00,Default,,0000,0000,0000,,three, four carbons, and so does\Nthis guy on the right.
Dialogue: 0,0:00:26.00,0:00:29.01,Default,,0000,0000,0000,,It has one, two, three,\Nfour carbons.
Dialogue: 0,0:00:29.01,0:00:32.40,Default,,0000,0000,0000,,This guy on the left\Nhas two, four, six,
Dialogue: 0,0:00:32.40,0:00:34.40,Default,,0000,0000,0000,,seven, eight hydrogens.
Dialogue: 0,0:00:34.40,0:00:38.08,Default,,0000,0000,0000,,This guy on the right has two,\Nfour, six, eight hydrogens.
Dialogue: 0,0:00:38.08,0:00:39.68,Default,,0000,0000,0000,,And they both have one oxygen.
Dialogue: 0,0:00:39.68,0:00:42.03,Default,,0000,0000,0000,,So both of the molecular\Nformulas for both of these
Dialogue: 0,0:00:42.03,0:00:47.31,Default,,0000,0000,0000,,things are four carbons, eight\Nhydrogens, and one oxygen.
Dialogue: 0,0:00:47.31,0:00:50.51,Default,,0000,0000,0000,,They're both C4H8O.
Dialogue: 0,0:00:50.51,0:00:52.20,Default,,0000,0000,0000,,So they have the same\Nmolecular formula.
Dialogue: 0,0:00:52.20,0:00:54.65,Default,,0000,0000,0000,,They're made up of the same\Nthing, so these are going to
Dialogue: 0,0:00:54.65,0:00:56.38,Default,,0000,0000,0000,,be isomers.
Dialogue: 0,0:00:56.38,0:00:57.74,Default,,0000,0000,0000,,They're going to be isomers,\Nand they're a
Dialogue: 0,0:00:57.74,0:00:59.46,Default,,0000,0000,0000,,special type of isomers.
Dialogue: 0,0:00:59.46,0:01:02.55,Default,,0000,0000,0000,,In this situation, we don't\Nhave the same bonds.
Dialogue: 0,0:01:02.55,0:01:05.57,Default,,0000,0000,0000,,We're made up of the same\Nthings, but the bonds, what is
Dialogue: 0,0:01:05.57,0:01:07.36,Default,,0000,0000,0000,,connected to what\Nis different.
Dialogue: 0,0:01:07.36,0:01:09.19,Default,,0000,0000,0000,,So we call this a constitutional\Nisomer.
Dialogue: 0,0:01:09.19,0:01:17.64,Default,,0000,0000,0000,,
Dialogue: 0,0:01:17.64,0:01:21.90,Default,,0000,0000,0000,,So we are essentially made up of\Nthe same things, but we are
Dialogue: 0,0:01:21.90,0:01:25.20,Default,,0000,0000,0000,,actually two different molecule,\Nactually, two very
Dialogue: 0,0:01:25.20,0:01:26.65,Default,,0000,0000,0000,,different molecules here.
Dialogue: 0,0:01:26.65,0:01:30.18,Default,,0000,0000,0000,,Now let's look at this\Nnext guy over here.
Dialogue: 0,0:01:30.18,0:01:34.60,Default,,0000,0000,0000,,So if we look at this molecule,\Nit does look like
Dialogue: 0,0:01:34.60,0:01:36.82,Default,,0000,0000,0000,,this carbon is chiral.
Dialogue: 0,0:01:36.82,0:01:38.97,Default,,0000,0000,0000,,It is an asymmetric carbon.
Dialogue: 0,0:01:38.97,0:01:42.82,Default,,0000,0000,0000,,It is bonded to four different\Ngroups: fluorine, bromine,
Dialogue: 0,0:01:42.82,0:01:45.09,Default,,0000,0000,0000,,hydrogen, and then\Na methyl group.
Dialogue: 0,0:01:45.09,0:01:46.74,Default,,0000,0000,0000,,And so's this one.
Dialogue: 0,0:01:46.74,0:01:49.20,Default,,0000,0000,0000,,And they're both made up\Nof the same things.
Dialogue: 0,0:01:49.20,0:01:51.45,Default,,0000,0000,0000,,You have the carbon-- and not\Nonly are they made up of the
Dialogue: 0,0:01:51.45,0:01:53.44,Default,,0000,0000,0000,,same things, but the bonding\Nis the same.
Dialogue: 0,0:01:53.44,0:01:56.74,Default,,0000,0000,0000,,So carbon to a fluorine, carbon\Nto a fluorine, carbon
Dialogue: 0,0:01:56.74,0:01:59.73,Default,,0000,0000,0000,,to a bromine, carbon to a\Nbromine, carbon to hydrogen in
Dialogue: 0,0:01:59.73,0:02:02.61,Default,,0000,0000,0000,,both of then carbon to the\Nmethyl group in both.
Dialogue: 0,0:02:02.61,0:02:05.02,Default,,0000,0000,0000,,But they don't look\Nquite the same.
Dialogue: 0,0:02:05.02,0:02:06.26,Default,,0000,0000,0000,,Are they mirror images?
Dialogue: 0,0:02:06.26,0:02:06.56,Default,,0000,0000,0000,,Well, no.
Dialogue: 0,0:02:06.56,0:02:09.44,Default,,0000,0000,0000,,This guy's mirror image would\Nhave the fluorine popping out
Dialogue: 0,0:02:09.44,0:02:14.92,Default,,0000,0000,0000,,here, the hydrogen going back\Nhere, and then would have the
Dialogue: 0,0:02:14.92,0:02:16.93,Default,,0000,0000,0000,,bromine pointing out here.
Dialogue: 0,0:02:16.93,0:02:19.60,Default,,0000,0000,0000,,Let's see if I can somehow get\Nfrom this guy to that guy.
Dialogue: 0,0:02:19.60,0:02:24.27,Default,,0000,0000,0000,,Let me flip this guy first. So\Nlet me-- a good thing to do
Dialogue: 0,0:02:24.27,0:02:30.52,Default,,0000,0000,0000,,would be to just flip to see\Nthe fastest way I could
Dialogue: 0,0:02:30.52,0:02:33.34,Default,,0000,0000,0000,,potentially get there.
Dialogue: 0,0:02:33.34,0:02:35.40,Default,,0000,0000,0000,,Let me just flip it like this.
Dialogue: 0,0:02:35.40,0:02:37.70,Default,,0000,0000,0000,,So I'm going to flip out of\Nthe page, you can imagine.
Dialogue: 0,0:02:37.70,0:02:39.66,Default,,0000,0000,0000,,I'm going to flip\Nit like this.
Dialogue: 0,0:02:39.66,0:02:41.87,Default,,0000,0000,0000,,So I'm going to take this methyl\Ngroup and then put it
Dialogue: 0,0:02:41.87,0:02:42.81,Default,,0000,0000,0000,,on the right-hand side.
Dialogue: 0,0:02:42.81,0:02:44.43,Default,,0000,0000,0000,,And you can imagine, I'm going\Nto turn it so it would come
Dialogue: 0,0:02:44.43,0:02:46.77,Default,,0000,0000,0000,,out of the page and\Nthen go back down.
Dialogue: 0,0:02:46.77,0:02:48.95,Default,,0000,0000,0000,,So if I did that, what\Nwould it look like?
Dialogue: 0,0:02:48.95,0:02:51.13,Default,,0000,0000,0000,,I would have the carbon,\Nthis carbon here.
Dialogue: 0,0:02:51.13,0:02:54.08,Default,,0000,0000,0000,,I would have the methyl group\Non that side now.
Dialogue: 0,0:02:54.08,0:02:57.59,Default,,0000,0000,0000,,And then since I flipped it\Nover, the bromine was in the
Dialogue: 0,0:02:57.59,0:02:58.52,Default,,0000,0000,0000,,plane of the page.
Dialogue: 0,0:02:58.52,0:03:02.91,Default,,0000,0000,0000,,It'll still be in the plane of\Nthe page, but since I flipped
Dialogue: 0,0:03:02.91,0:03:07.06,Default,,0000,0000,0000,,it over, the hydrogen, which was\Nin the back, will now be
Dialogue: 0,0:03:07.06,0:03:08.74,Default,,0000,0000,0000,,in the front.
Dialogue: 0,0:03:08.74,0:03:12.94,Default,,0000,0000,0000,,The hydrogen will now be in\Nthe front and the fluorine
Dialogue: 0,0:03:12.94,0:03:15.62,Default,,0000,0000,0000,,will now be in back because\NI flipped it over.
Dialogue: 0,0:03:15.62,0:03:20.32,Default,,0000,0000,0000,,So the fluorine is\Nnow in the back.
Dialogue: 0,0:03:20.32,0:03:22.87,Default,,0000,0000,0000,,Now, how does this\Ncompare to that?
Dialogue: 0,0:03:22.87,0:03:24.57,Default,,0000,0000,0000,,Let's see if I can somehow\Nget there.
Dialogue: 0,0:03:24.57,0:03:27.61,Default,,0000,0000,0000,,Well, if I take this fluorine\Nand I rotate it to where the
Dialogue: 0,0:03:27.61,0:03:30.30,Default,,0000,0000,0000,,hydrogen is, and I take the\Nhydrogen and rotate it to
Dialogue: 0,0:03:30.30,0:03:32.55,Default,,0000,0000,0000,,where-- that's all going to\Nhappen at once-- to where the
Dialogue: 0,0:03:32.55,0:03:34.72,Default,,0000,0000,0000,,bromine is, and I take the\Nbromine and rotate it to where
Dialogue: 0,0:03:34.72,0:03:36.53,Default,,0000,0000,0000,,the fluorine is, I get that.
Dialogue: 0,0:03:36.53,0:03:41.86,Default,,0000,0000,0000,,So I can flip it and then I can\Nrotate it around this bond
Dialogue: 0,0:03:41.86,0:03:44.55,Default,,0000,0000,0000,,axis right there, and I would\Nget to that molecule there.
Dialogue: 0,0:03:44.55,0:03:46.04,Default,,0000,0000,0000,,So even though they look pretty\Ndifferent, with the
Dialogue: 0,0:03:46.04,0:03:48.41,Default,,0000,0000,0000,,flip and a rotation, you\Nactually see that these are
Dialogue: 0,0:03:48.41,0:03:49.66,Default,,0000,0000,0000,,the same a molecule.
Dialogue: 0,0:03:49.66,0:03:55.34,Default,,0000,0000,0000,,
Dialogue: 0,0:03:55.34,0:03:56.59,Default,,0000,0000,0000,,Next one.
Dialogue: 0,0:03:56.59,0:03:58.05,Default,,0000,0000,0000,,So let's see, what\Ndo we have here?
Dialogue: 0,0:03:58.05,0:04:00.06,Default,,0000,0000,0000,,Let me switch colors.
Dialogue: 0,0:04:00.06,0:04:02.82,Default,,0000,0000,0000,,So over here, this part\Nof both of these
Dialogue: 0,0:04:02.82,0:04:03.96,Default,,0000,0000,0000,,molecules look the same.
Dialogue: 0,0:04:03.96,0:04:06.38,Default,,0000,0000,0000,,You have the carbons\Non both of them.
Dialogue: 0,0:04:06.38,0:04:08.57,Default,,0000,0000,0000,,This carbon looks like\Na chiral center.
Dialogue: 0,0:04:08.57,0:04:12.38,Default,,0000,0000,0000,,It's bonded to one, two,\Nthree different groups.
Dialogue: 0,0:04:12.38,0:04:14.47,Default,,0000,0000,0000,,You might say, oh, it's two\Ncarbons, but this is a methyl
Dialogue: 0,0:04:14.47,0:04:16.83,Default,,0000,0000,0000,,group, and then this side has\Nall this business over it, so
Dialogue: 0,0:04:16.83,0:04:18.70,Default,,0000,0000,0000,,this is definitely\Na chiral carbon.
Dialogue: 0,0:04:18.70,0:04:20.83,Default,,0000,0000,0000,,And over, here same thing.
Dialogue: 0,0:04:20.83,0:04:22.50,Default,,0000,0000,0000,,It's a chiral carbon.
Dialogue: 0,0:04:22.50,0:04:23.62,Default,,0000,0000,0000,,And this has the same thing.
Dialogue: 0,0:04:23.62,0:04:25.29,Default,,0000,0000,0000,,It's bonded to four\Ndifferent things.
Dialogue: 0,0:04:25.29,0:04:28.94,Default,,0000,0000,0000,,So each of these molecules has\Ntwo chiral carbons, and it
Dialogue: 0,0:04:28.94,0:04:31.47,Default,,0000,0000,0000,,looks like they're made\Nup of the same things.
Dialogue: 0,0:04:31.47,0:04:36.25,Default,,0000,0000,0000,,And not only are they made up\Nof the same things, but the
Dialogue: 0,0:04:36.25,0:04:39.09,Default,,0000,0000,0000,,bonds are made in\Nthe same way.
Dialogue: 0,0:04:39.09,0:04:42.83,Default,,0000,0000,0000,,So this carbon is bonded to a\Nhydrogen and a fluorine, and
Dialogue: 0,0:04:42.83,0:04:44.76,Default,,0000,0000,0000,,the two other carbons,\Nsame thing, a
Dialogue: 0,0:04:44.76,0:04:46.53,Default,,0000,0000,0000,,hydrogen and a fluorine.
Dialogue: 0,0:04:46.53,0:04:48.89,Default,,0000,0000,0000,,Carbon, it looks like\Nit's a hydrogen.
Dialogue: 0,0:04:48.89,0:04:53.31,Default,,0000,0000,0000,,It's bonded to a hydrogen and a\Nchlorine, so it's made up of
Dialogue: 0,0:04:53.31,0:04:55.35,Default,,0000,0000,0000,,the same constituents\Nand they're
Dialogue: 0,0:04:55.35,0:04:56.41,Default,,0000,0000,0000,,bonded in the same way.
Dialogue: 0,0:04:56.41,0:05:00.63,Default,,0000,0000,0000,,So these look like--\Nbut the bonding is
Dialogue: 0,0:05:00.63,0:05:01.82,Default,,0000,0000,0000,,a little bit different.
Dialogue: 0,0:05:01.82,0:05:04.96,Default,,0000,0000,0000,,Over here on this one on the\Nleft, the hydrogen goes in the
Dialogue: 0,0:05:04.96,0:05:07.51,Default,,0000,0000,0000,,back, and over here, the\Nhydrogen's in the front.
Dialogue: 0,0:05:07.51,0:05:10.31,Default,,0000,0000,0000,,And over here, the chlorine's\Nin back, and over here, the
Dialogue: 0,0:05:10.31,0:05:11.56,Default,,0000,0000,0000,,chlorine's in front.
Dialogue: 0,0:05:11.56,0:05:13.29,Default,,0000,0000,0000,,So these look like\Nsterioisomers.
Dialogue: 0,0:05:13.29,0:05:18.47,Default,,0000,0000,0000,,
Dialogue: 0,0:05:18.47,0:05:21.63,Default,,0000,0000,0000,,You saw earlier in this video,\Nyou saw structural isomers,
Dialogue: 0,0:05:21.63,0:05:23.29,Default,,0000,0000,0000,,made up of the same\Nthings but the
Dialogue: 0,0:05:23.29,0:05:24.69,Default,,0000,0000,0000,,connections are all different.
Dialogue: 0,0:05:24.69,0:05:27.92,Default,,0000,0000,0000,,Stereoisomers, they're made\Nup of the same thing, the
Dialogue: 0,0:05:27.92,0:05:30.38,Default,,0000,0000,0000,,connections are the same, but\Nthe three-dimensional
Dialogue: 0,0:05:30.38,0:05:32.80,Default,,0000,0000,0000,,configuration is a little\Nbit different.
Dialogue: 0,0:05:32.80,0:05:35.06,Default,,0000,0000,0000,,For example, here on this\Ncarbon, it's connected to the
Dialogue: 0,0:05:35.06,0:05:37.81,Default,,0000,0000,0000,,same things as this carbon, but\Nover here, the fluorine's
Dialogue: 0,0:05:37.81,0:05:40.75,Default,,0000,0000,0000,,out front, and over here--\Nout here, the
Dialogue: 0,0:05:40.75,0:05:41.40,Default,,0000,0000,0000,,fluorine's out front.
Dialogue: 0,0:05:41.40,0:05:43.10,Default,,0000,0000,0000,,Over here, the fluorine's\Nbackwards.
Dialogue: 0,0:05:43.10,0:05:44.54,Default,,0000,0000,0000,,And same thing for the\Nchlorine here.
Dialogue: 0,0:05:44.54,0:05:46.57,Default,,0000,0000,0000,,It's back here and\Nit's front here.
Dialogue: 0,0:05:46.57,0:05:52.77,Default,,0000,0000,0000,,Now, let's see if they're\Nrelated in a more nuanced way.
Dialogue: 0,0:05:52.77,0:05:55.78,Default,,0000,0000,0000,,You could imagine putting\Na mirror behind.
Dialogue: 0,0:05:55.78,0:05:57.47,Default,,0000,0000,0000,,I guess the best way to\Nvisualize it, imagine putting
Dialogue: 0,0:05:57.47,0:06:00.13,Default,,0000,0000,0000,,a mirror behind this molecule.
Dialogue: 0,0:06:00.13,0:06:02.94,Default,,0000,0000,0000,,If you put a mirror behind this\Nmolecule, what would its
Dialogue: 0,0:06:02.94,0:06:04.57,Default,,0000,0000,0000,,reflection look like?
Dialogue: 0,0:06:04.57,0:06:06.94,Default,,0000,0000,0000,,So if you put a mirror behind\Nit, in the image of the
Dialogue: 0,0:06:06.94,0:06:10.47,Default,,0000,0000,0000,,mirror, this hydrogen would now,\Nsince the mirror's behind
Dialogue: 0,0:06:10.47,0:06:12.75,Default,,0000,0000,0000,,this whole molecule, this\Nhydrogen is actually closer to
Dialogue: 0,0:06:12.75,0:06:13.45,Default,,0000,0000,0000,,the mirror.
Dialogue: 0,0:06:13.45,0:06:16.31,Default,,0000,0000,0000,,So then the mirror image, you\Nwould have a hydrogen that's
Dialogue: 0,0:06:16.31,0:06:19.53,Default,,0000,0000,0000,,pointed out, and then you would\Nhave the carbon, and
Dialogue: 0,0:06:19.53,0:06:22.77,Default,,0000,0000,0000,,then you would have the fluorine\Nbeing further away.
Dialogue: 0,0:06:22.77,0:06:24.93,Default,,0000,0000,0000,,And same thing in the\Nmirror image here.
Dialogue: 0,0:06:24.93,0:06:27.68,Default,,0000,0000,0000,,You would have the chlorine\Ncoming closer since this
Dialogue: 0,0:06:27.68,0:06:30.27,Default,,0000,0000,0000,,chlorine is further back, closer\Nto the mirror, and then
Dialogue: 0,0:06:30.27,0:06:33.23,Default,,0000,0000,0000,,you would have the hydrogen\Npointing outwards like that.
Dialogue: 0,0:06:33.23,0:06:36.29,Default,,0000,0000,0000,,And then, obviously, the rest\Nof the molecule would look
Dialogue: 0,0:06:36.29,0:06:38.79,Default,,0000,0000,0000,,exactly the same.
Dialogue: 0,0:06:38.79,0:06:42.18,Default,,0000,0000,0000,,And so this mirror image that I\Njust thought about in white
Dialogue: 0,0:06:42.18,0:06:45.71,Default,,0000,0000,0000,,is exactly what this molecule\Nis: hydrogen pointing out in
Dialogue: 0,0:06:45.71,0:06:49.80,Default,,0000,0000,0000,,front, hydrogen pointing\Nout in front.
Dialogue: 0,0:06:49.80,0:06:53.11,Default,,0000,0000,0000,,You might say, wait, this\Nhydrogen is on the right, this
Dialogue: 0,0:06:53.11,0:06:53.71,Default,,0000,0000,0000,,one's on the left.
Dialogue: 0,0:06:53.71,0:06:54.09,Default,,0000,0000,0000,,It doesn't matter.
Dialogue: 0,0:06:54.09,0:06:55.69,Default,,0000,0000,0000,,This is actually saying that\Nthe hydrogen's pointing out
Dialogue: 0,0:06:55.69,0:06:58.04,Default,,0000,0000,0000,,front, the fluorine is pointing\Nout back, hydrogen up
Dialogue: 0,0:06:58.04,0:07:02.01,Default,,0000,0000,0000,,front, fluorine back, chlorine\Nout front, hydrogen back,
Dialogue: 0,0:07:02.01,0:07:03.93,Default,,0000,0000,0000,,chlorine out front,\Nhydrogen back.
Dialogue: 0,0:07:03.93,0:07:06.93,Default,,0000,0000,0000,,So these are actually mirror\Nimages, but they're not the
Dialogue: 0,0:07:06.93,0:07:08.90,Default,,0000,0000,0000,,easy mirror images that we've\Ndone in the past where the
Dialogue: 0,0:07:08.90,0:07:12.75,Default,,0000,0000,0000,,mirror was just like that\Nin between the two.
Dialogue: 0,0:07:12.75,0:07:15.26,Default,,0000,0000,0000,,This one is a mirror image where\Nyou place the mirror
Dialogue: 0,0:07:15.26,0:07:18.30,Default,,0000,0000,0000,,either on top of or behind\None of the molecules.
Dialogue: 0,0:07:18.30,0:07:20.57,Default,,0000,0000,0000,,So this is a class of\Nstereoisomers, and we've
Dialogue: 0,0:07:20.57,0:07:22.13,Default,,0000,0000,0000,,brought up this word before.
Dialogue: 0,0:07:22.13,0:07:23.38,Default,,0000,0000,0000,,We call this enantiomers.
Dialogue: 0,0:07:23.38,0:07:26.00,Default,,0000,0000,0000,,
Dialogue: 0,0:07:26.00,0:07:29.03,Default,,0000,0000,0000,,So if each of these are an\Nenantiomers, I'll say they are
Dialogue: 0,0:07:29.03,0:07:30.83,Default,,0000,0000,0000,,enantiomers of each other.
Dialogue: 0,0:07:30.83,0:07:32.39,Default,,0000,0000,0000,,They're steroisomers.
Dialogue: 0,0:07:32.39,0:07:35.38,Default,,0000,0000,0000,,They're made up of the same\Nmolecules, so that they have
Dialogue: 0,0:07:35.38,0:07:36.68,Default,,0000,0000,0000,,the same constituents.
Dialogue: 0,0:07:36.68,0:07:40.12,Default,,0000,0000,0000,,They also have the same\Nconnections, and not only do
Dialogue: 0,0:07:40.12,0:07:42.09,Default,,0000,0000,0000,,they have the same connections,\Nthat so far gets
Dialogue: 0,0:07:42.09,0:07:45.10,Default,,0000,0000,0000,,us a steroisomer, but they are a\Nspecial kind of stereoisomer
Dialogue: 0,0:07:45.10,0:07:48.45,Default,,0000,0000,0000,,called an enantiomer, where they\Nare actual mirror images
Dialogue: 0,0:07:48.45,0:07:50.50,Default,,0000,0000,0000,,of each other.
Dialogue: 0,0:07:50.50,0:07:54.20,Default,,0000,0000,0000,,Now, what is this one\Nover here in blue?
Dialogue: 0,0:07:54.20,0:07:56.33,Default,,0000,0000,0000,,Just like the last one, it looks\Nlike it's made up of the
Dialogue: 0,0:07:56.33,0:07:57.54,Default,,0000,0000,0000,,same things.
Dialogue: 0,0:07:57.54,0:08:00.14,Default,,0000,0000,0000,,You have these carbons, these\Ncarbons, these carbons and
Dialogue: 0,0:08:00.14,0:08:01.02,Default,,0000,0000,0000,,hydrogens up there.
Dialogue: 0,0:08:01.02,0:08:02.59,Default,,0000,0000,0000,,Same thing over there.
Dialogue: 0,0:08:02.59,0:08:05.12,Default,,0000,0000,0000,,You have a hydrogen, bromine,\Nhydrogen and a bromine,
Dialogue: 0,0:08:05.12,0:08:08.10,Default,,0000,0000,0000,,hydrogen, chlorine, hydrogen,\Nchlorine, hydrogen, chlorine,
Dialogue: 0,0:08:08.10,0:08:09.21,Default,,0000,0000,0000,,hydrogen, chlorine.
Dialogue: 0,0:08:09.21,0:08:10.50,Default,,0000,0000,0000,,So it's made up of\Nthe same things.
Dialogue: 0,0:08:10.50,0:08:14.01,Default,,0000,0000,0000,,They're connected in the same\Nway, so they're definitely
Dialogue: 0,0:08:14.01,0:08:15.78,Default,,0000,0000,0000,,stereoisomers.
Dialogue: 0,0:08:15.78,0:08:17.51,Default,,0000,0000,0000,,Well, we have to make sure\Nthey're not-- well, let's make
Dialogue: 0,0:08:17.51,0:08:19.83,Default,,0000,0000,0000,,sure they're not the same\Nmolecule first. Here,
Dialogue: 0,0:08:19.83,0:08:21.52,Default,,0000,0000,0000,,hydrogen's in the front.
Dialogue: 0,0:08:21.52,0:08:23.77,Default,,0000,0000,0000,,There, hydrogen's in the back.
Dialogue: 0,0:08:23.77,0:08:25.60,Default,,0000,0000,0000,,Here, hydrogen is in the back.
Dialogue: 0,0:08:25.60,0:08:26.59,Default,,0000,0000,0000,,Here, hydrogen is\Nin the front.
Dialogue: 0,0:08:26.59,0:08:28.14,Default,,0000,0000,0000,,So they're not the\Nsame molecule.
Dialogue: 0,0:08:28.14,0:08:30.36,Default,,0000,0000,0000,,They have a different\Nthree-dimensional
Dialogue: 0,0:08:30.36,0:08:33.94,Default,,0000,0000,0000,,configuration, although their\Nbond connections are the same,
Dialogue: 0,0:08:33.94,0:08:35.19,Default,,0000,0000,0000,,so these are stereoisomers.
Dialogue: 0,0:08:35.19,0:08:44.43,Default,,0000,0000,0000,,
Dialogue: 0,0:08:44.43,0:08:46.35,Default,,0000,0000,0000,,Let's see if they're\Nenantiomers.
Dialogue: 0,0:08:46.35,0:08:49.41,Default,,0000,0000,0000,,So if we look at it like this,\Nyou put a mirror here, you
Dialogue: 0,0:08:49.41,0:08:50.72,Default,,0000,0000,0000,,wouldn't get this\Nguy over here.
Dialogue: 0,0:08:50.72,0:08:52.77,Default,,0000,0000,0000,,Then you would have a chlorine\Nout front and a hydrogen.
Dialogue: 0,0:08:52.77,0:08:55.14,Default,,0000,0000,0000,,So you won't get it if you\Nget a mirror over there.
Dialogue: 0,0:08:55.14,0:08:58.45,Default,,0000,0000,0000,,But if we do the same exercise\Nthat we did in the last pair,
Dialogue: 0,0:08:58.45,0:09:02.86,Default,,0000,0000,0000,,if you put a mirror behind this\Nguy, and I'm just going
Dialogue: 0,0:09:02.86,0:09:05.17,Default,,0000,0000,0000,,to focus on the stuff that's\Njust forward and back, because
Dialogue: 0,0:09:05.17,0:09:07.16,Default,,0000,0000,0000,,that's what's relevant\Nif the mirror is
Dialogue: 0,0:09:07.16,0:09:09.25,Default,,0000,0000,0000,,sitting behind the molecule.
Dialogue: 0,0:09:09.25,0:09:12.57,Default,,0000,0000,0000,,So if the mirror's sitting\Nbehind the molecule, this
Dialogue: 0,0:09:12.57,0:09:15.81,Default,,0000,0000,0000,,bromine is actually closer to\Nthe mirror than that hydrogen.
Dialogue: 0,0:09:15.81,0:09:20.68,Default,,0000,0000,0000,,So the bromine will now be out\Nfront and then the hydrogen
Dialogue: 0,0:09:20.68,0:09:21.38,Default,,0000,0000,0000,,will be in back.
Dialogue: 0,0:09:21.38,0:09:22.93,Default,,0000,0000,0000,,This hydrogen will\Nbe in the back.
Dialogue: 0,0:09:22.93,0:09:26.12,Default,,0000,0000,0000,,I'm trying to do kind of a\Nmirror image if it's hard to
Dialogue: 0,0:09:26.12,0:09:27.07,Default,,0000,0000,0000,,conceptualize.
Dialogue: 0,0:09:27.07,0:09:29.87,Default,,0000,0000,0000,,And then that would\Nall look the same.
Dialogue: 0,0:09:29.87,0:09:33.89,Default,,0000,0000,0000,,And then this chlorine will\Nnow be out front, and this
Dialogue: 0,0:09:33.89,0:09:37.72,Default,,0000,0000,0000,,hydrogen will now be in the back\Nin our mirror image, if
Dialogue: 0,0:09:37.72,0:09:39.18,Default,,0000,0000,0000,,you can visualize it.
Dialogue: 0,0:09:39.18,0:09:40.35,Default,,0000,0000,0000,,And then we have another one.
Dialogue: 0,0:09:40.35,0:09:43.23,Default,,0000,0000,0000,,And this chlorine is closer to\Nthe mirror that it's kind of
Dialogue: 0,0:09:43.23,0:09:44.94,Default,,0000,0000,0000,,been sitting on top of.
Dialogue: 0,0:09:44.94,0:09:47.10,Default,,0000,0000,0000,,So in the mirror image, it would\Nbe pointing out, and
Dialogue: 0,0:09:47.10,0:09:49.69,Default,,0000,0000,0000,,then this hydrogen would\Nbe pointing back.
Dialogue: 0,0:09:49.69,0:09:52.55,Default,,0000,0000,0000,,Now let's see, is our mirror\Nimage the same as this?
Dialogue: 0,0:09:52.55,0:09:54.94,Default,,0000,0000,0000,,So the mirror image, our bromine\Nis pointing in the
Dialogue: 0,0:09:54.94,0:09:57.14,Default,,0000,0000,0000,,front, hydrogen in\Nthe back there.
Dialogue: 0,0:09:57.14,0:10:00.69,Default,,0000,0000,0000,,Then we have hydrogen in-- then\Nin our mirror image, we
Dialogue: 0,0:10:00.69,0:10:02.27,Default,,0000,0000,0000,,have the hydrogen in back,\Nchlorine in front.
Dialogue: 0,0:10:02.27,0:10:02.77,Default,,0000,0000,0000,,Same there.
Dialogue: 0,0:10:02.77,0:10:05.46,Default,,0000,0000,0000,,So far, it's looking like\Na mirror image.
Dialogue: 0,0:10:05.46,0:10:08.69,Default,,0000,0000,0000,,And then in this last carbon\Nover here, chlorine in front,
Dialogue: 0,0:10:08.69,0:10:10.31,Default,,0000,0000,0000,,hydrogen in back.
Dialogue: 0,0:10:10.31,0:10:12.80,Default,,0000,0000,0000,,But here, we have chlorine in\Nthe back, hydrogen in front.
Dialogue: 0,0:10:12.80,0:10:15.75,Default,,0000,0000,0000,,So this part, you could\Nthink of it this way.
Dialogue: 0,0:10:15.75,0:10:20.36,Default,,0000,0000,0000,,This is the mirror image of\Nthis, this is the mirror image
Dialogue: 0,0:10:20.36,0:10:24.47,Default,,0000,0000,0000,,of this part, but this is not\Nthe mirror image of that part.
Dialogue: 0,0:10:24.47,0:10:27.79,Default,,0000,0000,0000,,So when you have a stereoisomer\Nthat is not a
Dialogue: 0,0:10:27.79,0:10:29.98,Default,,0000,0000,0000,,mirror, when you have two\Nstereoisomers that aren't
Dialogue: 0,0:10:29.98,0:10:34.33,Default,,0000,0000,0000,,mirror images of each other,\Nwe call them diastereomers.
Dialogue: 0,0:10:34.33,0:10:35.58,Default,,0000,0000,0000,,I always have trouble\Nsaying that.
Dialogue: 0,0:10:35.58,0:10:36.92,Default,,0000,0000,0000,,Let me write it.
Dialogue: 0,0:10:36.92,0:10:45.99,Default,,0000,0000,0000,,These are diastereomers, which\Nis essentially saying it's a
Dialogue: 0,0:10:45.99,0:10:48.24,Default,,0000,0000,0000,,stereoisomer that is\Nnot an enantiomer.
Dialogue: 0,0:10:48.24,0:10:50.47,Default,,0000,0000,0000,,That's all it means: a\Nstereoisomer, not an
Dialogue: 0,0:10:50.47,0:10:51.09,Default,,0000,0000,0000,,enantiomer.
Dialogue: 0,0:10:51.09,0:10:52.83,Default,,0000,0000,0000,,A stereoisomer's either going\Nto be an enantiomer or a
Dialogue: 0,0:10:52.83,0:10:54.96,Default,,0000,0000,0000,,diastereomer.
Dialogue: 0,0:10:54.96,0:10:57.04,Default,,0000,0000,0000,,Now, let's do this last one.
Dialogue: 0,0:10:57.04,0:11:02.65,Default,,0000,0000,0000,,Let's see we have two-- we have\Nthis cyclohexane ring,
Dialogue: 0,0:11:02.65,0:11:05.95,Default,,0000,0000,0000,,and they have a bromo on the\Nnumber one and the number two
Dialogue: 0,0:11:05.95,0:11:07.75,Default,,0000,0000,0000,,group, depending how\Nyou think about it.
Dialogue: 0,0:11:07.75,0:11:11.51,Default,,0000,0000,0000,,It looks like they are mirror\Nimages of each other.
Dialogue: 0,0:11:11.51,0:11:15.05,Default,,0000,0000,0000,,We could put a mirror right\Nthere, and they definitely
Dialogue: 0,0:11:15.05,0:11:16.64,Default,,0000,0000,0000,,look like mirror images.
Dialogue: 0,0:11:16.64,0:11:18.52,Default,,0000,0000,0000,,And this is a chiral\Ncarbon here.
Dialogue: 0,0:11:18.52,0:11:20.79,Default,,0000,0000,0000,,It's bonded to one carbon group\Nthat is different than
Dialogue: 0,0:11:20.79,0:11:21.55,Default,,0000,0000,0000,,this carbon group.
Dialogue: 0,0:11:21.55,0:11:23.17,Default,,0000,0000,0000,,This carbon group\Nhas a bromine.
Dialogue: 0,0:11:23.17,0:11:24.08,Default,,0000,0000,0000,,This carbon group doesn't.
Dialogue: 0,0:11:24.08,0:11:25.75,Default,,0000,0000,0000,,It just has a bunch of hydrogens\Non it, if you kind
Dialogue: 0,0:11:25.75,0:11:27.21,Default,,0000,0000,0000,,of go in that direction.
Dialogue: 0,0:11:27.21,0:11:30.64,Default,,0000,0000,0000,,And it's hydrogen and then a\Nbromine, so that is chiral.
Dialogue: 0,0:11:30.64,0:11:33.37,Default,,0000,0000,0000,,And then, same argument,\Nthat is also chiral.
Dialogue: 0,0:11:33.37,0:11:36.05,Default,,0000,0000,0000,,And obviously, this one is\Nchiral and that is chiral.
Dialogue: 0,0:11:36.05,0:11:38.88,Default,,0000,0000,0000,,But if you think about it, they\Nare mirror images of each
Dialogue: 0,0:11:38.88,0:11:42.37,Default,,0000,0000,0000,,other, and they each have\Ntwo chiral centers
Dialogue: 0,0:11:42.37,0:11:44.35,Default,,0000,0000,0000,,or two chiral carbons.
Dialogue: 0,0:11:44.35,0:11:46.84,Default,,0000,0000,0000,,But if you think about it, all\Nyou have to do is flip this
Dialogue: 0,0:11:46.84,0:11:49.83,Default,,0000,0000,0000,,guy over and you will\Nget this molecule.
Dialogue: 0,0:11:49.83,0:11:51.97,Default,,0000,0000,0000,,These are the same molecules.
Dialogue: 0,0:11:51.97,0:11:56.38,Default,,0000,0000,0000,,So it is the same molecule.
Dialogue: 0,0:11:56.38,0:11:59.05,Default,,0000,0000,0000,,So this is interesting, and we\Nsaw this when we first learned
Dialogue: 0,0:11:59.05,0:12:00.22,Default,,0000,0000,0000,,about chirality.
Dialogue: 0,0:12:00.22,0:12:03.35,Default,,0000,0000,0000,,Even though we have two chiral\Ncenters, this is
Dialogue: 0,0:12:03.35,0:12:04.65,Default,,0000,0000,0000,,not a chiral molecule.
Dialogue: 0,0:12:04.65,0:12:06.69,Default,,0000,0000,0000,,It is the same thing as\Nits mirror image.
Dialogue: 0,0:12:06.69,0:12:10.18,Default,,0000,0000,0000,,It is superimposable on\Nits mirror image.
Dialogue: 0,0:12:10.18,0:12:23.41,Default,,0000,0000,0000,,It is superimposable on\Nits mirror image.
Dialogue: 0,0:12:23.41,0:12:27.54,Default,,0000,0000,0000,,So even though it has chiral\Ncarbons in it, it is not a
Dialogue: 0,0:12:27.54,0:12:29.38,Default,,0000,0000,0000,,chiral molecule.
Dialogue: 0,0:12:29.38,0:12:31.53,Default,,0000,0000,0000,,And we call these\Nmeso compounds.
Dialogue: 0,0:12:31.53,0:12:34.70,Default,,0000,0000,0000,,
Dialogue: 0,0:12:34.70,0:12:36.51,Default,,0000,0000,0000,,And we can point to one of them\Nbecause they really are
Dialogue: 0,0:12:36.51,0:12:37.66,Default,,0000,0000,0000,,the same compound.
Dialogue: 0,0:12:37.66,0:12:41.59,Default,,0000,0000,0000,,This is a meso compound.
Dialogue: 0,0:12:41.59,0:12:43.77,Default,,0000,0000,0000,,It has chiral centers.
Dialogue: 0,0:12:43.77,0:12:45.96,Default,,0000,0000,0000,,It has chiral carbons, I\Nguess you could say it.
Dialogue: 0,0:12:45.96,0:12:48.36,Default,,0000,0000,0000,,But it is not a chiral\Ncompound.
Dialogue: 0,0:12:48.36,0:12:50.35,Default,,0000,0000,0000,,And the way to spot these fairly\Nstraightforward is that
Dialogue: 0,0:12:50.35,0:12:52.50,Default,,0000,0000,0000,,you have chiral centers,\Nbut there is a
Dialogue: 0,0:12:52.50,0:12:54.17,Default,,0000,0000,0000,,line of symmetry here.
Dialogue: 0,0:12:54.17,0:12:56.11,Default,,0000,0000,0000,,There's a line of symmetry\Nright here.
Dialogue: 0,0:12:56.11,0:12:59.69,Default,,0000,0000,0000,,These two sides of the compound\Nare mirror images of
Dialogue: 0,0:12:59.69,0:13:00.43,Default,,0000,0000,0000,,each other.
Dialogue: 0,0:13:00.43,0:13:05.19,Default,,0000,0000,0000,,Now, these would not be the same\Nmolecule if I change that
Dialogue: 0,0:13:05.19,0:13:09.31,Default,,0000,0000,0000,,to a fluorine and I change\Nthat to a fluorine.
Dialogue: 0,0:13:09.31,0:13:11.78,Default,,0000,0000,0000,,Then all of a sudden, you do\Nnot have this symmetry.
Dialogue: 0,0:13:11.78,0:13:14.18,Default,,0000,0000,0000,,These are mirror images,\Nbut they would not be
Dialogue: 0,0:13:14.18,0:13:15.06,Default,,0000,0000,0000,,superimposable.
Dialogue: 0,0:13:15.06,0:13:17.65,Default,,0000,0000,0000,,So if that was a fluorine,\Nthese would actually be
Dialogue: 0,0:13:17.65,0:13:18.79,Default,,0000,0000,0000,,enantiomers.
Dialogue: 0,0:13:18.79,0:13:22.11,Default,,0000,0000,0000,,And this would not be only one\Nmeso compound, it would be two
Dialogue: 0,0:13:22.11,0:13:27.86,Default,,0000,0000,0000,,different enantiomers, and one\Nof them would have an R
Dialogue: 0,0:13:27.86,0:13:30.34,Default,,0000,0000,0000,,direction and one of them would\Nhave an S direction if
Dialogue: 0,0:13:30.34,0:13:33.04,Default,,0000,0000,0000,,we go with the naming\Nconventions that we learned.
Dialogue: 0,0:13:33.04,0:13:35.47,Default,,0000,0000,0000,,