Chromophore-Appended C60 and C70 Fullerenes: Anthracene and Pyrene Derivatives – Syntheses, Cyclic Voltammetry, and Spectra

C60 and C70 adducts containing spacer-linked phenyl (BK1), 9-anthracenyl (BK2), 4-(9-anthracenyl)phenyl (BK3), and 1-pyrenyl groups (BE1 and FE1) have been studied. Two different synthetic pathways were employed based on the [4+2] cycloaddition of fullerenes with 2-trimethylsiloxy-1,3-butadienes (TB). Spectroscopic data for the new compounds are given. Electrochemical and optoelectrochemical studies were undertaken by using cyclic voltammetry and spectroelectrochemical methods. The fluorescence emission spectra of BK2, BK3, BE1, and FE1 are reported. Intramolecular energy transfer from the excited fluorophore to the fullerene subunit is shown to occur.