Dieldrin can be formed from the synthesis of hexachloro-1 ,3 - cyclopentadiene with norbornadiene in a Diels-Alder reaction , followed by epoxidation of the norbornene ring .
It can be formed from the synthesis of hexachloro-1 ,3 - cyclopentadiene with norbornadiene in a Diels-Alder reaction , followed by epoxidation of the norbornene ring .