Diels–Alder cycloadditions of functionalized (Z)-1-benzylidene-2-methylene cyclohexanes: the beneficial effect of high pressure

Diels–Alder cycloaddition reactions have been studied on substituted (Z)-1-benzylidene-2-methylene cyclohexanes 3. The use of very reactive dienophiles allowed the formation of the expected polycyclic structures whereas hyperbaric conditions (16 kbar) were necessary to form the adducts with less reactive dienophiles. An exo stereoselectivity was observed during the reaction with acrylates.