Give the IUPAC name for each of the following:

Question

b.

Accepted Answer

Hi, everybody. Our next problem says, provide the Iupac name of the compound below. And I have a lined structure here of a carbon chain that at first glance has an ethyl branch and a bromine on it. But we'll take a closer look at it in a moment. Our answer choices are a six bromo, three methyl heptane B five bromo, two ethyl hexane C two bromo, five ethyl hexane or D two bromo, phi methyl hep five methyl heptane. So my first step in finding an Iupac name is to find the longest carbon chain. When I first look at this line structure, I see that I have this long chain sort of horizontal with a two carbon chain coming down from it and a roaming coming up from it. So let's count the number of carbons there. I have one, 23456. However, when I look carefully here, since that ay group, the two carbon chain is on my second to last carbon. Instead of making that a branch, I can go down it as part of my chain. Since there's only one carbon left at the end, I will be replacing that one carbon with two carbons. So I'll make my chain instead of going horizontally all the way, add that second or second to last carbon, depending the way I was counting second to last carbon, I now go down two more into my ethyl group. So I now have 1234567 carbons in that chain. So instead of six, my longest carbon chain has seven carbons, which means that this is a Hept, there's no double bonds or triple bonds. So we have the Ain ending and hap being the prefix. So when I look at my answer, choices, I see that choice B and choice C are both called hexane. So they have the wrong chain labeled as the longest one. So we'll go ahead and cross them out. Hexane would be for six carbons. We just had A and D left to choose from. So my next step is to number the carbon atoms to give the lowest substituent number. So if I start from the left side of the molecule and number 123 in blue, I hit the methyl group on carbon three. If I start from the right side of the molecule on number and red, I label 12 and I get the bromine on carbon two. So starting from the left or starting from the right, excuse me, will give me the lowest substituent number. So we want to start from the right, which is my red numbers So I'll go ahead and erase the blue numbers and finish numbering my carbons here. I've numbered my seven carbons and now I look at my substituents. So on carbon two, I have a Bromine. So that will be numbered as two hyphen bromo in my name. And then on carbon five, there is a methyl group. So that would be five hyphen methyl. And then I just need to decide which order to put these in in front of my hept route there. And that would be an alphabetical order written ABC order. So Broen will be first. So I will have two BROMO coming first which I see. In choice D we have two bromo. Choice A has six promo. So in choice A, they clearly number the carbons in the other direction. But as we said, that makes the first substituent on carbon three rather than carbon two. And you can see in choice A it says three methyl. So choice A is wrong because they've numbered the carbons the wrong way. So after two bromo, we should see five methyl, which is here and then Heptane. So choice D is our answer. And the IOP name of this compound is choice D two bromo, five methyl Heptane. See you in the next video.

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Give the IUPAC name for each of the following:

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Give the IUPAC name for each of the following:b. <IMAGE>

Watch next

Naming Other Substituents practice set

Give the IUPAC name for each of the following:

b. <IMAGE>