[2]Catenanes Decorated with Porphyrin and [60]Fullerene Groups: Design, Convergent Synthesis, and Photoinduced Processes

作者：Jackson Dirceu Megiatto Junior, David I. Schuster, Silke Abwandner, Gustavo de Miguel, Dirk Michael Guldi · 发表于：Journal of the American Chemical Society · 年份：2010 · DOI：10.1021/ja910149f · 被引用次数：128 · 研究领域：Porphyrin and Phthalocyanine Chemistry、Fullerene Chemistry and Applications、Synthesis and Properties of Aromatic Compounds

A new class of [2]catenanes containing zinc(II)-porphyrin (ZnP) and/or [60]fullerene (C(60)) as appended groups has been prepared. A complete description of the convergent synthetic approach based on Cu(I) template methodology and "click" 1,3-dipolar cycloaddition chemistry is described. This new electron donor-acceptor catenane family has been subjected to extensive spectroscopic, computational, electrochemical and photophysical studies. (1)H NMR spectroscopy and computational analysis have revealed that the ZnP-C(60)-[2]catenane adopts an extended conformation with the chromophores as far as possible from each other. A detailed photophysical investigation has revealed that upon irradiation the ZnP singlet excited state initially transfers energy to the (phenanthroline)(2)-Cu(I) complex core, producing a metal-to-ligand charge transfer (MLCT) excited state, which in turn transfers an electron to the C(60) group, generating the ZnP-[Cu(phen)(2)](2+)-C(60)(*-) charge-separated state. A further charge shift from the [Cu(phen)(2)](2+) complex to the ZnP subunit, competitive with decay to the ground state, leads to the isoenergetic long distance ZnP(*+)-[Cu(phen)(2)](+)-C(60)(*-) charge-separated radical pair state, which slowly decays back to the ground state on the microsecond time scale. The slow rate of back-electron transfer indicates that in this interlocked system, as in previously studied covalently linked ZnP-C(60) hybrid materials, this process occurs in the Marcus-inve...