Control of Porphyrin Planarity and Aggregation by Covalent Capping: Bissilyloxy Porphyrin Silanes
Control of Porphyrin Planarity and Aggregation by Covalent Capping: Bissilyloxy Porphyrin Silanes
复制标题
通过共价封端控制卟啉平面性和聚集：双硅氧基卟啉硅烷
DOI：
10.1021/acs.inorgchem.0c01891
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发表时间：
2020
影响因子：
4.6
通讯作者：
Hussein B
中科院分区：
文献类型：
--
作者：
Hussein B
卟啉是一种重要的功能材料，可用于从分子电子学到生物学和医学的各种环境中。然而，它们的应用经常受到阻碍，这是由于它们的延伸的、疏溶剂的芳族表面导致的溶解性差。试图通过使其外围功能化来解决这一问题的努力只取得了有限的成功。在这里，我们展示了一个通用的策略，调整的物理和电子性质的卟啉使用轴向官能化的方法。卟啉硅烷（PorSil）和双甲硅烷基氧基PorSil（SOPS）通过操作简单的κ 4 N-甲硅烷基化方案由卟啉制备，引入位于平面卟啉中心且垂直于平面卟啉的大体积甲硅烷基氧基“帽”。虽然卟啉通常形成J-或H-聚集体，但SOPS不以相同的方式自缔合：甲硅烷基氧基轴向取代基通过抑制聚集显著改善溶解度。此外，轴向卟啉官能化提供了方便的处理，通过该处理可以调节卟啉核的光学、电子和结构性质。我们观察到，甲硅烷氧基取代基的身份影响卟啉在固态下的平面度以及氧化还原电位。
Porphyrins are cornerstone functional materials that are useful in a wide variety of settings, ranging from molecular electronics to biology and medicine. Their applications are often hindered, however, by poor solubilities that result from their extended, solvophobic aromatic surfaces. Attempts to counteract this problem by functionalizing their peripheries have been met with only limited success. Here, we demonstrate a versatile strategy to tune the physical and electronic properties of porphyrins using an axial functionalization approach. Porphyrin silanes (PorSils) and bissilyloxy PorSils (SOPS) are prepared from porphyrins by operationally simple κ4N-silylation protocols, introducing bulky silyloxy “caps” that are central and perpendicular to the planar porphyrin. While porphyrins typically form either J- or H-aggregates, SOPS do not self-associate in the same manner: the silyloxy axial substituents dramatically improve the solubility by inhibiting aggregation. Moreover, axial porphyrin functionalization offers convenient handles through which optical, electronic, and structural properties of the porphyrin core can be modulated. We observe that the identity of the silyloxy substituent impacts the degree of planarity of the porphyrin in the solid state as well as the redox potentials.