[Synthesisgirl]

Hey guys,

I did a Diels-Alder reaction. I was asked what the major and minor products were, and what distinct stereoisomers were present.

I said there were only two stereoisomers possible and I drew them out below.
I just wanted to make sure I was right .

Usually there would be more stereoisomers based on the ortho and para directing nature of a Diels-Alder, but because we have a symmetrical dienophile it is not the case, right?

I just want to make sure, because we are doing these Diels-Alder reactions in the lab for the first time but we have not been taught the Diels-Alder in the lecture class yet .

Thanks guys!

[Honclbrif]

Draw it out with the dienophile flipped top to bottom and see if the products are superimposable with the ones drawn the first way.

[fledarmus]

What about the mirror images of the two structures you have drawn? Would they be identical? If not, what would keep them from being formed?

EDIT - looks like Honclbrif beat me to it... 

[Synthesisgirl]

Draw it out with the dienophile flipped top to bottom and see if the products are superimposable with the ones drawn the first way.

Ahhh ok! My stereochemistry is very weak, this is a great exercise, thanks

I have added my two other stereoisomers... four stereoisomers is total!