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.

CNTs in Optoelectronic Devices: New Structural and Photophysical Insights on Porphyrin‐DWCNTs Hybrid Materials

“…As reported earlier for covalently‐linked fullerene‐porphyrin conjugates,27 several conformational equilibria can occur in solution 28, 29. Likewise, a dynamic equilibrium between “loose” and “tight” porphyrin‐CNTs pairs, in which the carbon nanotube and the porphyrin are in the “face‐to‐face” conformation in the ground state, can be considered ( Figure ).…”

Effect of Roux-en-Y gastric bypass on testosterone and prostate-specific antigen

“…His research involves fullerene chemistry, and photochemistry and photophysics, in particular porphyrin–fullerene donor–acceptor systems. He has reported in Chemistry—A European Journal on the synthesis of functionalized [3]catenanes,5b and on the synthesis and photophysics of porphyrin–fullerene dyads 5c…”

Ultrafast charge separation and charge stabilization in axially linked ‘tetrathiafulvalene–aluminum(iii) porphyrin–gold(iii) porphyrin’ reaction center mimics

“…Very few examples are known where the photoinduced processes are in the axial or perpendicular direction to the porphyrin plane. [19][20][21][22][23][24][25] This is mainly because of the synthetic challenges where two ligands cannot be attached using transition metal porphyrins. This problem can be addressed by using main group element porphyrins, such as aluminum(III) porphyrin, [26][27][28][29] tin(IV) porphyrin 27,[30][31][32][33][34][35][36] or phosphorus(V) porphyrins, 27,30,[37][38][39][40] which generally have one or two axial bonds and they can be utilized to attach redox active electron donor (D) and/or acceptor (A) units.…”