Part of a synthesis by E. J. Corey and David Watt (Harvard University) involves the Diel...

Part of a synthesis by E. J. Corey and David Watt (Harvard University) involves the Diels–Alder cycloaddition of the following pyrone and cyclohexenone. The initial reaction gives the endo product, which loses carbondioxide in a retro-Diels–Alder to generate a diene with predictable stereochemistry and functionality. IR and UV spectroscopy of the final product show that it contains a diene conjugated with an ester, and an unconjugated ketone. Determine the structures of the intermediate and the final product, with particular attention to their stereochemistry.