title: Synthesis, conformational interconversion, and photophysics of tethered porphyrin-fullerene dyads with parachute topology.
abstract: The synthesis of a porphyrin-fullerene dyad with "parachute" topology is reported. To determine whether the dyad is "flexing" at room temperature, low-temperature NMR experiments were used. Computational modeling has shown the low-energy conformation of the dyad to be nonsymmetric. Although, (1)H NMR spectroscopy at room temperature is consistent with a molecule with C(2v) symmetry, the spectrum changes on lowering the temperature consistent with "windshield wiper"-like motion, in which the porphyrin moiety rotates from one side of the C(60) sphere to the other. Nanosecond and picosecond fluorescence lifetime experiments show two components contribute to the fluorescence decay, also consistent with the presence of more than one conformer.
authors: Department of Chemistry, New York University, 100 Washington Square East, USA.
authors: Michael A
authors: MA
authors: Fazio
authors: Alexander
authors: A
authors: Durandin
authors: Nikolai V
authors: NV
authors: Tkachenko
authors: Marja
authors: M
authors: Niemi
authors: Helge
authors: H
authors: Lemmetyinen
authors: David I
authors: DI
authors: Schuster