If we consider that the diene and the dienophile can be both over each other ( dienophile above , diene below and vice vers ) , how do we define endo and exo then ?
great video! The dienes are enantiomers, so the products are also enantiomers, the dienophile is meso, I think you should say the stereochemistry is retained in diels alder rxns.
No, for the examples in the video, the dienes are not enantiomers and the dienophile is not a meso compound. All of the reactions shown are actually generating two new chiral centres in the products, but the reagents themselves are achiral. Although the product at 3:28 contains two asymmetric carbons it also contains a mirror plane so is a meso compound. For the product at 5:00 and the last example, you will get a pair of enantiomers as is demonstrated.
At 1:10 you said that the diene is trans with respect to the pi bonds, however, that is not the case. It is actually cis or s-cis with respect to the pi bonds, and it has to be in the s-cis conformation in order to react.
Can you plz explain this, u said both double bond are cis in one case and the other both are trans but with respect to what are u saying that theu are cis or trans they look the same to mw
![[UNCUT] บอสพอล แผลงฤทธิ์ บอสพระ-นักร้อง ก. โดนแฉยับ! I คนดังนั่งเคลียร์ I 21 ต.ค. 67](http://i.ytimg.com/vi/XKf6HeftoPI/mqdefault.jpg)
thankyou and i love you
U saved me thank u
If we consider that the diene and the dienophile can be both over each other ( dienophile above , diene below and vice vers ) , how do we define endo and exo then ?
great video! The dienes are enantiomers, so the products are also enantiomers, the dienophile is meso, I think you should say the stereochemistry is retained in diels alder rxns.
No, for the examples in the video, the dienes are not enantiomers and the dienophile is not a meso compound. All of the reactions shown are actually generating two new chiral centres in the products, but the reagents themselves are achiral. Although the product at 3:28 contains two asymmetric carbons it also contains a mirror plane so is a meso compound. For the product at 5:00 and the last example, you will get a pair of enantiomers as is demonstrated.
At 1:10 you said that the diene is trans with respect to the pi bonds, however, that is not the case. It is actually cis or s-cis with respect to the pi bonds, and it has to be in the s-cis conformation in order to react.
He is referring to each individual double bond, each one being trans in their own right, while the entire diene is s-cis, like you said.
can the dienophile be on the diene? and then it rearranges to react?
yea
HI where can i buy those plastic model for setereochemistry?
you can find them very easily on amazon. Just look up molecular modeling kits and you will find it easily.
Can you plz explain this, u said both double bond are cis in one case and the other both are trans but with respect to what are u saying that theu are cis or trans they look the same to mw
you r god
why isn't there stereochemistry needed for the CO2Me?
+Ralph Scianni .. Because that carbon is not chiral
Isnt there a way we can determine stereochemistry WITHOUT looking at models.... did it not occur to him that we cant use models in exams?....
🙌🏼👍🏼👏🏼👍🏼👍🏼👍🏼👍🏼👏🏼