Click the structures and reaction arrows in sequence to view the 3D models and animations respectively
There are very few examples of this kind of reaction due to the fact that it is difficult to make E,Z dienes. The diene reacts with an interesting dienophile: DEAD (diethyl azodicarboxylate). As expected, the resulting six-membered ring has trans stereochemistry with the methoxy group on the opposite face of the six-membered ring to the alkyl chain.
Examples of sterochemistry in trans,trans (E,E) and cis,cis (Z,Z) dienes.