Department of Chemistry, Indian Institute of Technology, Bombay, Powai, Mumbai 400 076, India.
Inorg Chem. 2011 Mar 7;50(5):1713-22. doi: 10.1021/ic102168f. Epub 2011 Jan 18.
Two examples of supramolecular tetrads containing Sn(IV) porphyrin, expanded thiaporphyrins such as sapphyrin and rubyrin, and Ru(II) porphyrin assembled using non-interfering cooperative tin(IV)-oxygen and ruthenium(II)-nitrogen coordination properties are described. These are the first examples in which the expanded porphyrins are used as axial ligands. The tetrads were prepared by adopting one step as well as stepwise approaches. In a one pot approach, the mono meso-pyridyl dihydroxy Sn(IV) porphyrin, meso-hydroxyphenyl expanded thiaporphyrin, and Ru(II) porphyrin were reacted in benzene under refluxing conditions followed by column chromatographic purification on alumina to afford tetrads. In a stepwise approach, the axial bonding type of triads containing Sn(IV)porphyrin as central unit and expanded thiaporphyrins as axial ligands were synthesized first by reacting meso-pyridyl dihydroxy Sn(IV) porphyrin with meso-hydroxyphenyl expanded thiaporphyrin in benzene at refluxing temperature. In the next step, the triads were reacted with Ru(II) porphyrin under mild reaction conditions to afford tetrads in decent yields. Both methods worked efficiently and produced stable, soluble tetrads in decent yields. One-dimensional (1D) and two-dimensional (2D) NMR techniques were used to confirm the identity of these novel tetrads. Absorption and electrochemical studies indicated that the components in tetrads interact weakly and retain their individual characteristic features. The steady state photophysical studies revealed that the quantum yield of Sn(IV) porphyrin in tetrads was reduced significantly because of non-radiative decay pathways operating in these systems.
两个含有锡（IV）卟啉、扩展硫代卟啉（如 sapphyrin 和 rubyrin）和钌（II）卟啉的超分子四联体的例子被描述，这些例子使用非干扰的协同锡（IV）-氧和钌（II）-氮配位性质组装而成。这些是首次将扩展卟啉用作轴向配体的例子。这些四联体是通过采用一步法和分步法制备的。在一锅法中，单中 - 吡啶二羟基锡（IV）卟啉、中 - 羟基苯基扩展硫代卟啉和 Ru（II）卟啉在苯中回流条件下反应，然后通过氧化铝柱层析纯化得到四联体。在分步法中，首先通过在苯中回流温度下使中 - 吡啶二羟基锡（IV）卟啉与中 - 羟基苯基扩展硫代卟啉反应，合成了以锡（IV）卟啉为中心单元和扩展硫代卟啉为轴向配体的三联体的轴向键合类型。在下一步中，在温和的反应条件下，将三联体与 Ru（II）卟啉反应，以相当高的产率得到四联体。这两种方法都非常有效，并且以相当高的产率产生稳定、可溶的四联体。一维（1D）和二维（2D）NMR 技术用于确认这些新型四联体的身份。吸收和电化学研究表明，四联体中的组件相互作用较弱，并保留其各自的特征。稳态光物理研究表明，由于这些体系中存在非辐射衰减途径，四联体中锡（IV）卟啉的量子产率显著降低。
