Iron and Porphyrin Metal–Organic Frameworks: Insight into Structural Diversity, Stability, and Porosity

Reaction
of iron­(IIII)­chloride with the free base tetrakis­(4-carboxyphenyl)­porphyrin
(H2TCPP) in the presence of different bases leads to the
formation of a series of iron/porphyrin metal–organic frameworks.
Such a crystal engineering approach led to the obtaining of four structures
presenting three different topologies and inorganic secondary building
units. Depending on the synthesis conditions, isolated FeIII octahedra, diiron­(II) paddle wheel dimers, or extended [FeIII(OH)­O4]n chains could be obtained
in a controlled manner. The influence of the synthetic conditions
on the final structure and the oxidation state of iron is discussed.
Stability of the porous solids towards air and water is studied, and
their intrinsic porosity is assessed.

在不同碱的存在下，氯化铁(III)与游离碱型四(4-羧基苯基)卟啉（tetrakis(4-carboxyphenyl)porphyrin, H2TCPP）发生反应，可生成一系列铁/卟啉基金属有机框架（metal–organic frameworks）。此种晶体工程策略可得到四种结构，这些结构涵盖三种不同的拓扑结构以及无机次级结构基元（secondary building units）。通过调控合成条件，可可控地获得孤立的三价铁八面体配位结构、二铁(II)桨轮型二聚体，或是延伸型的[FeIII(OH)O4]n链状结构。本文探讨了合成条件对最终产物结构以及铁元素氧化态的影响。本研究对该多孔固体在空气与水环境中的稳定性进行了考察，并对其固有孔隙特性进行了表征。