Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3060, United States.
Chem Rev. 2022 May 11;122(9):7990-8052. doi: 10.1021/acs.chemrev.1c00694. Epub 2022 Mar 18.
The replacement of one or more pyrrolic building block(s) of a porphyrin by a nonpyrrolic heterocycle leads to the formation of so-called pyrrole-modified porphyrins (PMPs), porphyrinoids of broad structural variability. The wide range of coordination environments (type, number, charge, and architecture of the donor atoms) that the pyrrole-modified frameworks provide to the central metal ions, the frequent presence of donor atoms at their periphery, and their often observed nonplanarity or conformational flexibility distinguish the complexes of the PMPs clearly from those of the traditional square-planar, dianionic, N-coordinating (hydro)porphyrins. Their different coordination properties suggest their utilization in areas beyond which regular metalloporphyrins are suitable. Following a general introduction to the synthetic methodologies available to generate pyrrole-modified porphyrins, their general structure, history, coordination chemistry, and optical properties, this Review highlights the chemical, electronic (optical), and structural differences of specific classes of metalloporphyrinoids containing nonpyrrolic heterocycles. The focus is on macrocycles with similar "tetrapyrrolic" architectures as porphyrins, thusly excluding the majority of expanded porphyrins. We highlight the relevance and application of these metal complexes in biological and technical fields as chemosensors, catalysts, photochemotherapeutics, or imaging agents. This Review provides an introduction to the field of metallo-PMPs as well as a comprehensive snapshot of the current state of the art of their synthesis, structures, and properties. It also aims to provide encouragement for the further study of these intriguing and structurally versatile metalloporphyrinoids.
卟啉的一个或多个吡咯环被非吡咯杂环取代，会形成所谓的吡咯修饰卟啉（PMP），这是一类结构多变的卟啉类似物。吡咯修饰骨架为中心金属离子提供了广泛的配位环境（配体的类型、数量、电荷和结构），其外围通常存在供体原子，而且常常具有非平面或构象灵活性，这些特点将 PMP 配合物与传统的平面正方形、二价阴离子、N 配位（水合）卟啉配合物明显区分开来。它们不同的配位性质表明，它们在常规金属卟啉适用的领域之外具有应用潜力。本文在对生成吡咯修饰卟啉的各种合成方法进行了一般性介绍之后，详细讨论了其一般结构、历史、配位化学和光学性质，并重点介绍了含有非吡咯杂环的特定类别的金属卟啉类似物的化学、电子（光学）和结构差异。本文的重点是与卟啉具有相似“四吡咯”结构的大环，因此排除了大多数扩展卟啉。我们强调了这些金属配合物在生物和技术领域作为化学传感器、催化剂、光化学治疗剂或成像剂的相关性和应用。本文为金属 PMP 领域提供了介绍，并全面概述了其合成、结构和性质的最新进展。本文还旨在鼓励进一步研究这些有趣且结构多样的金属卟啉类似物。
