Department of Chemistry and Center for Theoretical and Computational Chemistry, University of Tromsø, 9037 Tromsø, Norway.
Inorg Chem. 2012 Sep 17;51(18):9911-6. doi: 10.1021/ic301388e. Epub 2012 Sep 6.
A first major study of undecaphenylcorrole (UPC) derivatives is presented. Three different Cu-UPC derivatives with different para substituents X (X = CF(3), H, CH(3)) on the β-aryl groups were synthesized via Suzuki-Miyaura coupling of Cu[Br(8)TPC] and the appropriate arylboronic acid. A single-crystal X-ray structure of the X = CF(3) complex revealed a distinctly saddled macrocycle conformation with adjacent pyrrole rings tilted by 60-66° relative to one another (within the dipyrromethane units), which is somewhat higher than that observed for β-unsubstituted Cu-TPC derivatives but slightly lower than that observed for Cu[Br(8)TPC] (70°) derivatives. Electrochemical and electronic absorption measurements afforded some of the first comparative insights into meso versus β substituent effects on the copper corrole core. The Soret maxima of the Cu-UPC complexes (~440-445 nm), however, are comparable to those of Cu[Br(8)TPC] derivatives and are considerably red-shifted relative to Cu-TPC derivatives. Para substituents on the β-phenyl groups were found to tune the redox potentials of copper corroles more effectively than those on meso-phenyl substituents, a somewhat surprising observation given that neither the HOMO nor LUMO has significant amplitudes at the β-pyrrolic positions.
首次对未取代苯基卟啉（UPC）衍生物进行了重要研究。通过 Suzuki-Miyaura 偶联反应，将 Cu[Br(8)TPC]与适当的芳基硼酸反应，合成了三种不同的具有不同对位取代基 X（X = CF(3), H, CH(3)）的 Cu-UPC 衍生物。X = CF(3) 配合物的单晶 X 射线结构揭示了一个明显的马鞍形大环构象，相邻的吡咯环彼此倾斜约 60-66°（在二吡咯甲烷单元内），这比未取代的 Cu-TPC 衍生物略高，但比 Cu[Br(8)TPC]（70°）衍生物略低。电化学和电子吸收测量首次提供了一些关于取代基在铜卟啉核心中的中位与β位效应的比较见解。然而，Cu-UPC 配合物的 Soret 最大值（440-445nm）与 Cu[Br(8)TPC]衍生物相当，并且相对于 Cu-TPC 衍生物明显红移。β-苯基上的取代基被发现比中位苯基取代基更有效地调节铜卟啉的氧化还原电位，这一观察结果有些令人惊讶，因为 HOMO 和 LUMO 都没有在β-吡咯位置上具有显著的幅度。
