Draw the condensed structural or line-angle formula, if cyclic...

Question

Draw the condensed structural or line-angle formula, if cyclic, for each of the following:

b. 3-chloropropionaldehyde

Accepted Answer

Welcome back, everyone. Our next problem says, write the condensed structural formula if straight chain or line angle formula, if cyclic of five bromo Valer aldehyde, and we have four condensed structural formulas here labeled A through D and all of them are various lengths, carbon chains with an aldehyde group and a bromine substituent. So we'll look at these in more detail as we work through this name and look at what the structure must be. So we don't have to decide we're only presented with condensed structural formulas. So we know we have a straight chain. And indeed, when we look at our name, there's no cyclo prefix or benzene in there. So we see this valor aldehyde. Well, valor is one of these prefixes from the common names rather than the Iupac names. It is a name for a five carbon chain. We don't hear this one very often. You much more frequently hear things like formaldehyde acid aldehyde. But valor as a prefix means a five carbon chain. So we know we have a five carbon chain plus an aldehyde group, which of course will be that are bonded to a carbon, which is a double bond to an oxygen and then a hydrogen on its other side, because this group itself has a carbon in it. That's one of the five carbons in the chain. And then we have this bromine substituent. So for our condensed structural formula, we know we have bonds indicated. And then the ch groups are written as a group of letters, we don't show every single carbon hydrogen bond. So let's draw a series of five Carmens. I'll put a space there between each one to make room for fitting in those hydrogens. So that's 45, the last carbon or first carbon. However, you wanna draw it. But our answer choices, I'll have the aldehyde group at the end, we'll have a double bond to an oxygen and then a hydrogen on the other side. So there's her aldehyde group. The next step will be to number this chain so we can put on the substituents. So I'm going to number it in red. The aldehyde is the most, the highest priority functional group here. So we start the numbering with number one on the carbon. That's part of the aldehyde group and then 2345. And our name tells us that the bromine is on carbon five, it's five bromo valor aldehyde. So the bromine will put out bonded to the terminal carbon there. So on the opposite end from the aldehyde group, that is our only substituent. So the last step is just to fill in the hydrogen atoms. So we're going down in order because it's just easier to go left to right. I think. So, starting with carbon five has the bromine on one side and another carbon on the other. So it will have two hydrogens. We've got an H two there. Carbon four, same thing. It's an internal carbon. So it has two hydrogens, carbon three, no substituents, internal carbon, two hydrogens, carbon two, same thing. two hydrogens, carbon one, we already have the hydrogen. That's part of its being an aldehyde. It has a double bond to an oxygen and then a bond to a carbon one hydrogen is all it gets. So we have our structure. Let's look at our answer choices to match the correct one. Choice. A right away we can see is incorrect because the bromine is coming off of the second carbon rather than the final carbon. So we do have 12345 carbons. The bromine is on carbon four. So that makes choice a incorrect choice. B has the bromine on the second carbon and then 123456 that has too many carbons. So bromine is on carbon five, but we have six carbons in the chain. So that makes choice B incorrect as well. Now we move on to choice C, the bromine is on that terminal carbon. We count 12345 carbons and the aldehyde. On the end of the last, we have the correct number of hydrogens there. So it looks like choice C must be our answer to be thorough. We'll take a quick look at Joyce D. We have Bromine first and then 123456 carbons. So choice D is incorrect. Since this is a six carbon chain, those choices with the six carbons probably are looking to confuse you thinking that you need to have five carbons plus the aldehyde group. But when the functional group itself includes a carbon, it's one of the carbons in the chain. So our answer choice here for the condensed structural formula for five bromo Valer aldehyde is choice C got brch two ch two ch two ch two and C double bonded to an O and then a hydrogen. See you in the next video.

Draw the condensed structural or line-angle formula, if cyclic, for each of the following:
b. 3-chloropropionaldehyde

Key Concepts

Condensed Structural Formula

Line-Angle Formula

Functional Groups

Watch next