Give a correct name for each compound.
(a)

Question

Give a correct name for each compound.

(a)

(b)

Accepted Answer

hey everyone. Let's solve this problem. It says right, are you packed names for the following al canes? And we have to al keane's let's review the steps that we would take to solve this problem. The first step is technically optional. But I highly recommend drawing out the compound, especially if it has substitue in groups or side groups coming off of the parent chain. So may be helpful with substitue in groups and I say that or maybe helpful because that might help you identify which carbon chain is the longest. And also you might have to add some double bonds when you are drawing out your substitution groups. Okay, so if you see these substitution groups in the parentheses coming off of your main parent chain, I would recommend drawing it out. Then you're going to identify the longest carbon chain that includes the double bomb. Okay, so there might be say a six carbon chain but if there's a five carbon chain that involves the double bond, you want to include the double bond. Okay. In your longest chain then once we identify how many carbons are in our parent chain, we're going to name that parent chain with a number of carbons that will determine the prefix. And of course we'll have our ending in for our double bond or elkin. Then if we have three or more carbons we will have to number that double bond. Okay, and remember that you want to have the lowest number possible. So you basically want to start numbering numbering your parent chain closest to the double bond. And just to remind you if we have two double bonds we will call it a dying. If we have three double bonds that will be trying four, that would be tetra in so forth. So you're using those prefixes for not only how many carbons you have, but you're using prefixes for how many double bonds you have as well. And lastly that's it for the parent chain. Then we need to identify the name and location of substitution groups or those branches coming off of your parent chain. Okay, so let's apply these steps to our compounds that we have here. So I'm just going to draw out those substituting groups. Like I said, it doesn't have to be all the way. But that last carbon has a hydrogen and two ethyl groups. Ch two Ch 3, C H two ch three. And then we have another CH two, see H double bonded to CH two. Okay, so the reason why, like I said, it's good to draw out the substitution groups is because now we're going to identify our longest carbon chain, including the double bond. And we see that we can extend that numbering through one of these ethyl groups. Right? And so we're going to start closest to the double bond, right? And we're going to number one 2, 3, 4, 5, 6 carbons. Okay, So six carbons is hex right? The prefects hex. And since we have more than three carbons we're going to include the number that the number carbon that our double bond is on, which in this case would be one. And of course our ending in so we have hex one in that's our parent chain. And now let's add our substitue in groups. So we just have this ethyl group On Carbon # four. So we can add in front of it for ethel. Okay. And you can also write the number of the double bond location out front of the parent chain which would be for ethel one heck scene. Okay, so both of those are acceptable for our first compound. Does that make sense? Let's do compound B. So again we have a substitution group in the parentheses. So I'm just going to right, what's there? But draw the substitution group coming off C ch two CH two, CH two, CH 3. Okay, so we drew it out. Now let's identify the longest carbon chain, including the double bond. Well, the problem says these are all kinds but do you see a double bond? No, but do we need to add one? That was not written out? Yes, because it's not in the parent chain. Notice that this carbon here that has a CH two group only has three sigma bonds. Right. 123. So and these carbons in the chain have four sigma bonds. So they don't need any extra electrons. But this CH two group also will need some extra electrons. So if we make this a double bond that will satisfy both of their octet. It's okay, so that changes the way we're numbering, right? Because remember we have to include the double bond in our longest out Kane, or sorry, Joaquin chain. And we're starting our number numbering closest to that double bond. So we're not starting from either of these ends, We're starting right there in the middle. I know it sounds anti intuitive, right? But we're starting closest to that Al Keen and there's three carbons on either side of the center of carbon. So it doesn't matter which way you number it. I'm just going to go to the left. So 12345. So that will give us the prefix pent right, five carbons. And again, are all keen is on carbon number one. So pent one in and our substitue in group is actually the rest of this chain that you didn't expect that when you first looked at it. Right? So again, that's why it could be helpful to draw it out. So this is 123 carbons, methyl ethyl pro bowl. So and this is on carbon number two of our parent chain. So we have two pro po pent one in or two Pro po you can't see that two proposal one Pantene. Okay, so those are the two different ways you can write the name of this compound, The AIPac name, I hope this video was helpful. And thanks for watching

Give a correct name for each compound.
(a)
(b)

Key Concepts

IUPAC Nomenclature

Alkene Structure and Naming

Substituents and Branching

Watch next