Satoshi Ito, Takashi Murashima, Noboru Ono and Hidemitsu Uno
Heating 4,7-dihydro-4,7-ethano-2H-isoindole at 200 °C induces the retro-Diels–Alder reaction to give isoindole in essentially quantitative yield, which can be applied to a new synthesis of tetrabenzoporphyrins and monobenzoporphyrins.