PHOTOLYSIS AND RADIOLYSIS OF THE BENZENE‐FUMARONITRILE SYSTEM

Abstract— The photolytic and radiolytic product formation of the complex benzene‐fumaronitrile are compared. The equilibrium constants for the complexes of benzene‐fumaronitrile and benzene‐maleonitrile determined by UV and NMR spectroscopy are given. The products which were found in both photolysis and radiolysis of the system benzene‐fumaronitrile were biphenyl. phenylsuccinodinitrile and maleonitrile. The production of a 2:1 adduct of fumaronitrile and benzene in very small yields could only be confirmed in the case of photolysis. Additional products in radiolysis were phenylcyclohexadienes and benzonitrile. Experiments using filtered light proved that isomerisation of fumaronitrile to maleonitrile and production of phenylsuccinodinitrile proceed via the excited charge‐transfer complex. There are indications that the excited charge transfer complex is likewise an intermediate in the radiolytic formation of these nitriles. The addition of fumaronitrile to benzene reduces the yield of biphenyl in both photolysis and radiolysis.