Write the IUPAC name for each of the following: (12.3)
c.

Question

Write the IUPAC name for each of the following: (12.3)

c.

Accepted Answer

Welcome back everyone. Our next question says, what is the Iupac name of the compound shown below? And we have a line, a skeletal structure with a carbon chain that has 123456 carbons. It has a carbon group on the second to last carbon and a chlorine group on the carbon adjacent to it. Our answer choices are a four Chloro five hexagon B, four Chloro five methyl, five pone, C three Chloro two hexagon or D two Chloro one methyl, one pone. So let's think through our rules for naming a compound, we always start by finding the longest carbon chain. So as we look at our molecule, it is indeed the chain that is the sort of zigzag, the line structure here. There aren't any funny branches or things we could go off of or alternate ways of counting it. So as we said earlier, we have 123456 carbons in that chain. So six carbons and we have a carbonel group, the carbonel group is internal. So it has two R groups. We recall that when we have an R group attached to a carbon which has another group. On the other side, this is a kone. So we have six carbons with a ketone. So we use our root name, which would be hexane and add on at the end to show that it has a ketone. So that would be hexagon. And then if necessary, we indicate where on the chain, the key carbon carbon is. So that means we need to number this chain. So we want to number it so that the carbonel group, which is our primary substituent has the lowest possible number. So in this case, that's pretty straightforward from the perspective of looking at left to right, that carbonel group is the second to last carbon atom. So we'd want to side start from the side closest to that, but we're closer to the middle. We'd want to count to double check. But here it's pretty easy to tell. So the carbon to the farthest right would be carbon number one. I'm labeling in little red numbers. Our carbonyl is on carbon two. Then we have carbon three with the chlorine group 456. So to locate our ketone, we see it's on carbon two. So it will be two hyphen hexagon. So then our last step is to locate and name any substituents. So in this case, the only other group here is that chlorine, it's on carbon three. So that will be three hyphen chloro. There are no other substituents. So we don't need to worry about what order to put them in. So we just put those two things together. And for our name, we have three hyphen Chloro, we need another hyphen to separate it from the two hyphen hexagon. So there's our name and we see that corresponds with choice C when we look at our other answer, choices, choice A is four Chloro five hexagon. So that would describe our molecule, but it's numbered in the wrong order. So it started from the other end and ends up giving our substituents, particularly our ketone, the mu a much higher number. So that's why choice A is incorrect. Choice B says four Chloro five methyl, five pone and that splits up the chain. Whereas when we say have that own, we know it's a ketone. We know it's internal. We don't need to name the last carbon as a separate R group. So choice B is incorrect because we name the longest chain as a single name. Choice D says two chloro one methyl, one Pentium. And again, that's naming the two R groups on either side of the ketone separately. Whereas again, we go by the longest carbon chain, we know it's a ketone. We know it's internal. All we need is the number to tell us which carbon is involved in the carbon bond. So choice D is incorrect. So once again, the Iupac name of this compound is choice C three Chloro two hexagon. See you in the next video

Write the IUPAC name for each of the following: (12.3)
c. <IMAGE>

Verified video answer for a similar problem:

Key Concepts

IUPAC Nomenclature

Functional Groups

Structural Representation