Question
Which of the following conjugated dienes would not react with a dienophile in a Diels-Alder reaction?
Which of the following conjugated dienes would not react with a dienophile in a Diels-Alder reaction?

Answers
Which of the following conjugated dienes would not react with a dienophile in a Diels-Alder reaction?
Go on reaction. So we always want to orient her dying Facer dying a file. But we always want the withdrawing group to be facing inward. When this reacts, you're going to form this cycle. Maxine, this car box like gas and Steri chemistry is not, as we indicated for this compound for B, we have this dying reacting with this same file. It's our end product is going to be this cycle Hex Dean Earth, um, Ethel and this next group attached again, Sarah chemistry just not have spend initiated the 3rd 1 We have the Stein reacting with this Diana file. Sorry. State fish, actually, to my fingers touched here, the end product is going to be It's like a vaccine and again, those necessary chemistry which needs to be indicated for any of these
This is the answer to Chapter 16. Problem number 19 fromthe Smith Organic chemistry. Textbook on in this problem, we're asked to rank these three dying's in order of increasing reactivity in a deal's all the reaction. Ah, and so remember that for a dying to be reactive into deals, all the reaction, it has to be able to adopt an s sis confirmation. Ah. And so, looking at this first molecule, we could redraw this, um, so that it does have the SS confirmation so we could draw it like this. Um, and in this case, uh, it's going to have the es ist confirmation. So if we redraw it like this, uh, it's gonna have the esus confirmation on and so that's good. That's what we're looking for. So this is going to be reactive in a deal's all the reaction, but we don't yet know how it's gonna compare to these other two molecules that we have. Um, and so looking at the other two molecules, we see that this center molecule is, um, permanently locked into an assist Confirmation because it's a ring. And so this I'm gonna go ahead and say this is going to be the most reactive because it's always in that assist. Confirmation. Ah, And so the third molecule, uh, is locked also by the fact that it's it's in a rank on, and it's locked into the S trans confirmation. So this is going to be are the least reactive? Um, so actually, probably not reactive at all. Eso least reactive. And that would make this first molecule, um, the intermediate. So it's going to be somewhat reactive, but not as reactive as the second molecule on the third molecules. Not going to be reactive. It all. Ah, and again remember to arrive at this conclusion we were looking at which of these molecules can adopt an s assist confirmation. Ah, and the middle molecules locked in that confirmation. The third molecule can't adopt it at all on the first molecule is not in that confirmation, but it can assume that confirmation. Okay. And so that's the answer to Chapter 16. Problem number 19
This is the answer to Chapter 16. Problem number 29 from the Smith Organic Chemistry textbook on In this Problem were asked what dying and dying a file are needed to prepare each compound by a deal's older reaction. Ah, and so I think, probably the way to start this problem. Eyes to redraw these two ball and stick model molecules that we've been given as skeletal structure's, Um, my opinion. It's much easier to look at a skeletal structure. Ah, and so that's what I've done. Ah, And then in order to solve these, we can think about, uh, moving electrons. Thio sort of undo the deal's all the reaction. Ah, and to get back our dying and dying a file. Also, we should note, since, um, our molecules here in both cases refused rings. We're going to start with one ring, um, and then another molecule. So each of the right sides of these reactions here should have one ring in them. Okay? And so for a we can think about moving are electrons like this? And when we do that, we will get, uh, these two molecules. So here is our five member ring with two double bonds in it. So there's are dying on. Then our Diana file is going to be, uh, this. So there's our Diana file CEO too. Ch three. Okay, so there are two pieces that we would use to make a buy deals all the reaction on, and then we could do the same thing for B. We can think about moving these electrons. It's just sort of undo a deal's older, and so that would look like this. And like this and like this. And when we move those electrons in that fashion, um, we get this piece Oops. So we get this piece Ah, and then this piece, So are dying eyes to the left. And this molecule is our dying a file, even though it's also ah dying. Um, you know, it's not a conjugated dying. And so yeah, those are our pieces for B. And so that's that's all that we have to do here. Um, as I said, probably redraw the molecules, um, from the ball and stick models. Draw them a skeletal structures on, then just move electrons para cyclically, um, to undo a deal's older reaction. Ah, and that's the answer to Chapter 16. Problem number 29
This is the answer to Chapter 16. Problem number 51 from the Smith Organic Chemistry textbook. Ah, and this problem asks us what dying and Diana file are needed to prepare. Each deals all their product. So we have six steals all their products on. We need to come up with the dying's and Nina files from from which they were made. Ah. And so, in order to do this, um, probably the easiest way is to just drawn the reverse parasitic quick reaction of the one that, um, made these products. Ah. And so remember, that's gonna be just electrons moving in a circular fashion and then just drawing what the product of those electron movements would be A So for a that's gonna look like this. So there's are dying on. Then our Diana file would be this. Okay, uh, and so that's pretty much what we're gonna do for the other five. So, um, Paris cyclic electron movement for be actually looks exactly the same as for a, um, and the starting materials are are similar as well. Um, we just have to take into account. The difference is Okay, so there is our dying on then our Diana file is going to be Thank you. That molecule. Okay. And so that's B. And as I said, we'll just do the same thing for each of these s o here for See, um, it might be a little harder to see because this is too fused rings. But if you follow the movement of the electrons, you get the two products here. And so since this is too few strings, we know that one of the starting materials is going to be a ring already. And so this is gonna be our dying, and then our Diana file is going to look like this. Okay, Uh, so that c so then for D, uh, we could do the exact same thing. Ah, and so when we actually look, uh, these two pieces here, these air actually the exact same molecule. So it would be to equivalents of this one starting material. Okay, Uh, so then for E, it looks like I forgot a double bond in E. Um, so there would be a double bond right here. It's an important piece. Can forget that. Ah, and then the electron movement here is gonna look just like the electron movement and see looked okay. And so are products. Um, are again going to be a five member ring to sun without anoxia gin in it. Okay, there's our dying on Diana file is going to look like this. All right, on then. So lastly for F um, f it's sort of Ah, large, somewhat complicated molecule. Uh, so we need to just focus in on the sixth of central six members ring with the double bond in it. That's gonna be the one that forms from the deal's all the reaction. Ah, and we know that because, uh, because of the double bond, so remember, there's gonna have to be a residual double bond as a result of deals. All the reaction. So that's where we're going to draw our Paris cyclic reaction. Um, and when we do that, so there's our dying, Uh, and then the Diana file is going to be this molecule, okay. And so that's Ah, that's the answer here again, we arrived. These answers by drawing the parasite, click the movement of electrons that is the opposite of the way they moved to form a deal's alder product. Ah, and so that gets us back to our starting materials. And that's the answer to Chapter 16. Problem number 51