Diels-Alder Reactions of Substituted Cyclohexa-2,4-dienones with Alkenes and Alkynes

Substituted cyclohexa-2,4-dienones, generated in situ by pyrolysis of the appropriate dimer, participated in Diels-Alder reactions with various dienophiles to afford bicyclo[2.2.2]octenone and bicyclo[2.2.2]octadienone derivatives in high yields.