Draw condensed structures for the compounds represented by the...

Question

Draw condensed structures for the compounds represented by the following models (black = C, gray = H, red = O, blue = N, and green = Cl):

a.

b.

Accepted Answer

Hi, everybody. Let's take a look at our next question. It says, what are the condensed structures of the following compounds? Drawn as models? And then we have two compounds as our question says, drawn as ball and stick models that we need to transform into condensed structures. We have a color code, it tells us that the black balls are carbon white, are hydrogen, red, are oxygen and green are chlorine. So let's look at number one and to decide how best to write this as a condensed structure. I'd like to first sketch out, let's see how these are actually grouped together to see how to write it more efficiently as a condensed structure recall that in condensed structures, no bonds are shown and we write carbon hydrogen groups together with parentheses if they're repeating units and substituents are indicated with parentheses uh next to like to the, to the right of whatever uh group they're bonded to. So first, let's just get an idea of how these things are together. So our first model, we see kind of a main chain with 12345 carbons right off the bat and a chlorine on the end, sometimes it can be a little tricky to tell is something a substituent or part of the chain. Um You're rendering a 3d structure on a two D shape. In this case, we have ach three substituent. But in this case, it's kind of set, it looks like it's right behind the second carbon in the chain. So it's a little easier in this case to see it's a substituent. Sometimes it can get really tricky with longer chains. But then you should always notice that there's only, there's three hydrogens on this carbon there. If it were part of the chain, you would only see two hydrogens. So that should tell you as well. So we have this main chain that I will highlight in blue and then we have this substituent a little red dot there that's going behind the chain, a methyl group there. So I'm going to draw it as I'll write CH three and then we've got a bond to ach subunit and then I'll draw the line going up to the CH three. Obviously, this isn't the condensed structure because I don't indicate bonds or arrange them above or below each other in space. But this is to help me compose the most tidiest condensed structure. And then I have C two C two. So two of those. And then finally, I have ach two cl there at the end. So to write it as a pro con and structure, I want everything all in one line. Now, I actually have two ways I could write this. I could write it as CH three, my first group in the chain and then I could write CH and in parentheses CH three to indicate that methyl group substituent on carbon two. But this gets a little confusing because next, I have two CH, two units which I'd want to put as CH two in parentheses and then a two subscript indicating as two repeating units that looks a little bit confusing and tidy next to the parentheses. So let me cross that out and write this maybe in a little more clearer way. So looking at the end of the chain, I have the end of the chain and then a methyl group on the second carbon. So I can actually write that as in parentheses, ch three subscript two. So like two methyl groups stuck on the end of the chain that separates it from my second set of parentheses a little bit and makes it a little easier to read. So the two methyl groups and then the CH group, now I have two repeating CH two units. So in parenthesis, I write CH two subscript to now, why don't I include the last CH two? Because there's one more CH two on there with AC L. Why wouldn't I include that in the parenthesis there? Well, because this one has a bond to a chlorine as well, not another carbon. So I don't want to create any confusion as to where my chlorine is bonded. Otherwise, I might think it was on one of the other carbons there. So this one, I have to write out separately ch two cl. So that's the answer for number one. Now, let's look at number two. So I have now my main chain which is 1234 carbons and then there's an oxygen, it's an ether and then another carbon. And then in terms of substituents, I have a double bond to an oxygen and then I have one little methyl group sticking off. Well, it wouldn't be carbon two. If I'm numbering in the proper Iupac order, it would be the second to last carbon in the chain, but a little methyl group substitute off of that. So let's write out my sort of bonds and then we'll put it in a condensed structure format. So from left to right, I have CH three and then ch, and then I'll draw line up to the methyl group coming off that second carbon. Then I have a CH two, then I have my carbonel group. So I draw c and then I'll put a double bond going up to the oxygen. Well, I have bonds here to this isn't an official structure, so I can put bonds there. I'll put little bonds in between each of those main chain groups and then linked to the carbon carbon. I have an oxygen and linked to that, I have a methyl group CH three. So now let's put this all in one line in a condensed structure format. So here I don't have any confusing middle parentheses. So I'll go ahead and write it as CH three and then CH and then in parentheses, CH three indicating a methyl group off of that second carbon. Then we'll write CH two. Now my carbon carbon and then the next carbon is our carbon carbon, which has a double bond in oxygen and a single bond in oxygen. So again, we don't show bonds in condensed structures. We'll just write C and then we actually ate 02 sorry has two oxygens and then CH three. So that's our condensed structure or number one, we have CH three and parenthesis subscript two CH and then in parentheses, ch two subscript two CH two CL and then for molecule number two, ch three, ch then in parentheses, ch three, ch 2 co2 CH three. So there we go all in one line, no bonds and parentheses indicating our substituents. See you in the next video.

Draw condensed structures for the compounds represented by the following models (black = C, gray = H, red = O, blue = N, and green = Cl):
a. <IMAGE>
b. <IMAGE>

Key Concepts

Condensed Structures

Functional Groups

Molecular Geometry

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