Synthesis and Photoinduced Intramolecular Processes of Fulleropyrrolidine-Oligothienylenevinylene-Ferrocene Triads

Two new triads based on N‐methylfulleropyrolidine, oligothienylenevinylenes (nTV) and ferrocene (Fc), namely C60‐nTV‐Fc (n=2, 4) have been synthesized. A HOMO–LUMO gap as low as 1.09–1.11 eV was experimentally determined by cyclic voltammetry. In both polar and nonpolar solvents, photoinduced charge‐separation (CS) processes in C60‐nTV‐Fc predominantly take place from the singlet excited states of C60 and nTV; this result was indicated by steady and time‐resolved emission spectroscopy. In the case of C60‐4TV‐Fc, the CS state was indicated by the nanosecond transient absorption spectra. In C60‐2TV‐Fc, although the CS process was also confirmed by the fluorescence quenching in nonpolar and polar solvents, the lifetimes of the CS states were shorter than those of C60‐4TV‐Fc. It was revealed that the introduction of Fc donor moiety at the end of the longer nTV chain in the C60‐nTV dyad systems effectively increases the CS efficiency and the lifetimes of CS states. Two new triads based on N‐methylfulleropyrolidine (C60), oligothienylenevinylenes (nTV) and ferrocene (Fc), namely C60‐nTV‐Fc (n=2, 4), have been synthesized (see figure; m=1 or 3). The photoinduced charge‐separation (CS) process in C60‐nTV‐Fc predominantly takes place from the 1C60*. The introduction of the Fc donor moiety at the end of the longer nTV chain in the C60‐nTV dyad systems increases the CS efficiency and the lifetimes of CS states.