What dienes and dienophiles would react to give the following ...

Question

What dienes and dienophiles would react to give the following Diels–Alder products?

(d) Chemical structure of a Diels-Alder product featuring two methoxy groups and carbonyl functionalities.

(e) Chemical structure of a compound with a methoxy group and four cyano groups attached to a cyclohexene ring.

(f) Chemical structure diagram illustrating a Diels-Alder product with labeled functional groups and hydrogen atoms.

Accepted Answer

All right. Hello everyone. So this question is asking us to draw the plausible starting Dien and Dienno files needed to form the following products of which we have two. All right. So first, I'm going to scroll down very briefly just to talk more about the deal's older reaction aim the type of product that it's going to form. So here recall that the deal's older reaction can otherwise be referred to as a four and two cyclo addition and the two reagents necessary for deals older are a conjugated, dying as well as a day in or fail. Now, a conjugated diane has two pi bonds that are separated by one sigma bond in between them. This diane must be able to exist in the S sis confirmation where the two py bonds are pointing in the same direction. Now, our other reagent is the Diop which describes either ake or an all kind that has an electron withdrawing substituent or is electron deficient. And so four carbons from the conjugated dien combined with two from the dienno to create a six member ring. But to be more precise, the specific product obtained from a deal's older reaction is a cyclohexane. R I want to introduce a numbering scheme for the cyclohexane rings. We're going to label the carbons of the ring from one through six with carbon number one being at the top and proceeding in a counterclockwise direction. Carbons one through four of the new ring come from the conjugated dyne and carbons five and six come from the dienno file. Now there's also going to be a pi bond in between carbons two and three of the new ring. This is because of how the pi electrons of both the diane and the Diop move during the deals all the reaction. So by locating the cyclohexane ring in both of the products provided, we can separate that into both the dying and the dying of fat. So that means that we can separate the bonds in between carbons one and six and in between carbons four and five, this is going to give us the two starting materials necessary. So let's go ahead and do that and let's start with part one here. So I'll scroll back up. The first thing I'm going to do in the provided structure here. The provided product is look for the cyclohexane ring from there. I'm going to go ahead and label my carbons in the same way I did previously, carbon one is going to be on the top and then I label my remaining carbons going in a counterclockwise direction from here. I'm going to separate or rather, I'm going to imagine breaking the bonds between carbons, one and six and carbons four and five. This separates my product into fragments that come from both the diane and the dyno file. But a few things are worth keeping in mind here. First of all, the given products for part one does have one carbon that's bridged above the new ring. This is because that one carbon stemmed from the conjugated dyane, which happened to be a ring. So four carbons from the dying itself and one more from the bridge in the final product means that the diane was part of a five member ring. This gives me the dying after separating that fragment and adding double bonds in between carbons, one and two and in between carbons three and four. Now let's talk about the Diano file. Now, during this retro synthesis, in other words, going backwards to find the starting materials, there should be an extra double bond in between carbons five and six after you break the bond of the ring itself. And so what that means is that right now in the structure of the final product, there's a double bond in between carbons five and six. This means that in the structure of the starting material of the Diop one more P bond should be added to make it an all kind. So the Diop file here is an all kind with two of my substituents. And from here, part one is complete. So now let's do the same thing with part two. First, we're going to identify the Cyclohexane ring and label our carbons from 1 to 6 to separate these carbons into fragments from both the diane and diana. I'm going to break the bonds between carbons, one and six and carbons four and five. On the left side of that split is my day in which I am showing here in the S SIS confirmation. And on the other end, I have my Diop. So because there's only a single bond in between carbons five and six in the structure of the final product, the Diop was an all keen and there you have it, here are the answers for parts one and two. And so with that being said, thank you so very much for watching and I hope you found this helpful.

What dienes and dienophiles would react to give the following Diels–Alder products?
(d)
(e)
(f)

Key Concepts

Diels–Alder Reaction

Dienes and Dienophiles

Functional Groups

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