Using IUPAC rules, name the following molecules.
(d)

Question

Using IUPAC rules, name the following molecules.

(d)

Accepted Answer

Hello and welcome everyone. Our next problem says use Iupac rules and write the molecule name for the given structure. And our structure is a cyclopse ring. So it has a five carbons with a double bond on one of the carbons of the double bond, there's an isopropyl group. And then on one of the, on the other side of the double bond, the beta carbon has a solid wedge with an oh group on it. We have multiple choice options here for the name. So choice A says S3 isopropyl cyclops, two en all br three hydroxy, one isopropyl cyclops, C three hydroxy, one TERT beal one cyclops or de one isopropyl five hydroxy cyclops one E. So let's start thinking about how we systematically work through to find our name. So we first start by identifying the highest priority a top priority functional group. So our top priority in this molecule is a little tricky because we see that double bond and often those double bonds or triple bonds are the first thing we start with. But in this case, our alcohol group is our top priority. So with that in mind, we know that we will end our molecule with that L ending. And then we can go to our longest carbon chain, which in this case is our five carbon ring. So our sort of base name will be cyclops. So five carbons in a ring. And so we know we have that double bond. So we've got AC C double bond, which if it were just, if there were no oh group, it would just be the ending ene, But we need to combine that with that ol ending. It will have to be an Enna. So last thing we need to think about in this base name is we need to have a number to show us where the double bond is. Well, when numbering our ring top priority functional group should be carbon one. So we'll label the carbon with the oh group as number one. Then carbon two, we need to keep going to give the other substituents the lowest number possible. So we'll go in the direction of the double bond. So carbon two is the first carbon in that double bond, carbon three, the second and then 45. So to label where our double bond is, it's on carbon two. So the base name here would then be cyclops, hyphen two hyphen eal. Now you'll sometimes see the two out in front like two cyclops, but that's sort of an older system. The current Iupac rules say that the two should be inserted internally like this. Do we need to number where the alcohol is. No, we don't. If this were a carbon chain, the alcohol could probably be on like a carbon two or three if we internal in the chain. But since we have a ring, we can start our numbering wherever. And we know that with that oil ending, the alcohol is automatically on carbon one. So we don't need to specify that. Now, we just need to look at our substituents. Well, we've got the alcohol group substituent, but that's already been dealt with in adding that all to the base name. So we just have the isopropyl group which is on carbon three. So three isopropyl with a hyphen after the number note that isopropyl isn't sort of the official official name. That chain could be two methyl ethyl, but that's a little wordy. So it's acceptable to use isopropyl to describe this. So put it all together and we have three isopropyl. Oops put a hyphen. I don't need a hyphen straight into cyclo two in all. Well, one last thing we need to do, we mentioned the oh group is on a solid wedge. We need to use that R and S labeling. So next RS labeling to show the stereo chemistry. However, this question has multiple choice options. So before I spend time figuring out my stereo chemistry, I should look at my answer choices and see if I can eliminate enough that I might even get to my correct answer by process of elimination. So we said our first step was what's our top priority group? And we know we have to have that OL ending. Well, that's going to allow us to cross out BC and D right away. All of them have the alcohol group listed as a hydroxy substituent with the ending being being E but that is not correct. This is the wrong top priority. So we could have actually reached our correct answer by elimination. Even earlier in this process, we've only got one left and that is choice A which matches our name. Now from this, we already know that we have an S stereo chemistry but just to be thorough here in case you didn't have multiple choice questions or couldn't eliminate answers like this, let's think about why this is an s uh isomer. So let's look at that chiral center. We see we do have four different groups. There's a hydrogen and oh group and our chain or excuse me, our ring is not symmetrical. So our lowest priority will be the hydrogen. Since the oh group is on a solid wedge, my hydrogen must be on a dashed wedge, right? That's really messy. Looking, there's my hydrogen, the hydrogen is in the back. So with our lowest priority in the back, let's number our other substituents. The oh group will be number one. And let's think about our two other carbons here. There's two carbons. So we've got to go to the other bonds, those carbons have to distinguish between them. So carbon two, it's a carbon. And then in parentheses, we've got a double bond. So we count that as two bonds to a carbon. So it's CC and then it would have a hydrogen, one hydrogen on it. And then carbon five on the other side, it's a carbon also. And in parentheses, it has it no substituents. So it's seeds bonded to carbon four and then hh so you see the difference carbon two with two carbons, carbon five with only one. So our second priority group would be that carbon two and our third priority group, carbon five. So do I go count clockwise or counterclockwise? Well, to go from 1 to 2 to 3, that is counterclockwise. So with lowest priority in the back counterclockwise, that is the S isomer. So that does confirm our correct answer for the name here is choice a S3 isopropyl cyclops two en all see you in the next video.

Using IUPAC rules, name the following molecules.
(d)

Key Concepts

IUPAC Nomenclature

Functional Groups

Carbon Chain Structure

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Using IUPAC rules, name the following molecules.(d)

Key Concepts

IUPAC Nomenclature

Functional Groups

Carbon Chain Structure

Watch next

Using IUPAC rules, name the following molecules.
(d)