5-Norbornene-2-carboxaldehyde (CAS NO.5453-80-5) is also called 2-Formyl-5-norbornene ; 5-Formylbicyclo-2-heptene ; 5-Formylbicyclohept-2-ene ; 5-Norbornane-2-carboxaldehyde ; 5-norbornene-2-carboxaldehyde,mixtureofendoandexo ; Bicyclo[2.2.1]hept-5-en-2-aldehyde .