A bisfullerene-bis(dipyrrinato)zinc complex: Electronic coupling and charge separation in an easy-to-assemble synthetic system

A study was conducted to demonstrate the synthesis and photophysical characterization of a bisfullerene-bis(dipyrrinato)zinc complex for facile tethering of two fullerene subunits. Significant information was gathered about the synthesis and photopysical characterization of the complex from fluorescence measurements. It was found that redox- and photoinactive substituents played a significant role in modulating the basic properties of fulleropyrrolidines. Electrochemical investigations of the complex with dichloromethane provided thermodynamic information about the competition between electron and energy transfer. It was demonstrated that use of a (dpy)-Zn-(dpy) linker allowed the facile tethering of two fullerene subunits and produced an electronically coupled system that allowed effective charge separation after photoexitation. The zinc linker acted as a versatile redox relay and ensured the efficient mediation of charges across the fullerene unit.