| Abstract
| - Two complementary series of C60-(Fl)n and C60-(Fl)n-C60 (Fl = 9,9-dihexylfluorene-2,7-diyl; n = 1−5)derivatives with terminal N-methylfulleropyrrolidine units have been synthesized from CHO-(Fl)n andCHO-(Fl)n-CHO precursors via 1,3-dipolar cycloaddition reaction of in situ generated azomethine ylideswith an excess of C60. In solution electrochemical experiments, these conjugates give rise to amphotericredox behavior. Three consecutive quasireversible reduction waves have been observed at the expectedpotentials for the N-methylfulleropyrrolidine cores. For the C60-(Fl)n-C60 series, each reduction wave isa two-electron process with no observable interaction between the C60 units. Two or, in some cases,three oxidation wavesmost of them irreversibleare ascribed to the oligofluorene system. These wavesare cathodically shifted with an increasing number of fluorene units and anodically shifted by the conjugatedterminal aldehyde units, compared to the N-methylfulleropyrrolidine termini. Steady-state and time-resolvedphotolytic techniques show that an efficient transduction of singlet excited-state energy transfer prevailsfrom the photoexcited oligofluorene to the energy accepting fullerene.
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