High-Valent Metal Tetrapyrroles for Surface-Supported Catalysis

四吡咯的大环为具有催化活性的金属离子提供了自然界最通用的配位位点之一。金属和卟啉是这类天然丰富的催化分子中最著名的成员。金属四吡啶具有易于获取、坚固耐用和易于调节的特性，已成为催化剂、治疗药物、体内生物标志物或染料敏化光伏电池等先进系统的关键成分。它们稳定高氧化态金属离子（如+III， +IV和+V）的特性使它们具有选择性催化活性，具有新的应用前景，例如通过Mn(III), Fe(III), Au（III）或Ga（III）消除肿瘤和动脉粥样硬化预防。最近的液相研究表明，金属在小分子活化（如O2和CO2）中的作用具有很高的潜力。由于在20世纪90年代末之前克服了严重的合成障碍，所以在过去的几十年里，碳的化学基本上没有得到发展，到目前为止，几乎所有的研究都是在液相中进行的。因此，关于固体表面支撑的微粒的电子性质、构象和功能的基本知识仍有待探索。我们的建议涉及研究、表征和开发由技术相关的金属和半导体表面（Au, Si）支持的基于corrole的剂体系，以改善小分子活化。我们专注于精心挑选的金属或角色，这些金属或角色被认为是液相中选择性O2和CO2还原的潜在催化分子。作为比较参考，我们将同时研究相关的卟啉配合物。通过采用明确定义的表面模板，不仅有助于高价中心金属离子的稳定，而且还可以作为有前景的技术平台，从而提高催化性能。我们将全面表征决定特定催化活性的基本性质和过程。我们的提案是由来自奥地利和德国的四个互补研究小组在实验和理论物理以及合成和分析化学方面的专业知识之间的跨学科反馈导向的合作。基于已经存在的合作，我们进行协调一致的实验多技术研究（低温扫描隧道显微镜；光电子，x射线吸收，磁共振和光谱学；电化学），结合从第一原理出发的最先进的模型计算。我们的长期愿景是控制功能化金属和卟啉，支持技术相关的表面模板，用于选择性小分子活化。

The macrocycle of tetrapyrroles provides one of nature’s most versatile coordination sites for catalytically active metal ions. Metallocorroles and porphyrins are the best known members of this class of naturally abundant catalytic molecules. The facile access, robustness, and easily tunable properties have established metallotetrapyrroles as key components in advanced systems like catalysts, therapeutics, in‐vivo biomarkers, or dye‐sensitized photovoltaic cells. Their characteristic ability of stabilizing metal ions in high oxidation states such as +III, +IV and +V bestows them selective catalytic activity for reactive pathways prospective for novel applications such as, e. g., tumor elimination via Mn(III), Fe(III), Au(III) or Ga(III) and atherosclerosis prevention. Recent liquid‐phase investigations have indicated a high potential of metallocorroles for small‐molecule activation (e. g. O2 and CO2). The chemistry of corroles remained largely undeveloped for decades because of severe synthetic obstacles that were overcome not before the late 1990s and, so far, literally all studies have been conducted in liquid phase. Thus, the fundamental knowledge on the electronic properties, conformation and functionality of corroles supported on solid surfaces remains to be explored.Our proposal concerns the investigation, characterization and development of corrole‐based agent systems supported by technologically relevant metal and semiconductor surfaces (Au, Si) for improved small‐molecule activation. We focus on well‐selected metallocorroles that are regarded as prospective catalytic molecules for the selective O2 and CO2 reduction in the liquid phase. As a reference for comparison, we will simultaneously investigate the related porphyrin complexes. An improved catalytic performance is aspired by employing well‐defined surface templates that assist not only the desired stabilization of high‐valent central metal ions, but act as prospective technological platforms, as well. We shall comprehensively characterize the elementary properties and processes that determine specific catalytic activities. Our proposal is an interdisciplinary feedback‐oriented collaboration between four complementary research groups from Austria and Germany with dedicated expertise in experimental and theoretical physics as well as synthetic and analytic chemistry. Based on already existing collaborations, we perform concerted experimental multi‐technique investigations (low temperature scanning tunneling microscopy; photoelectron‐, X-ray absorption, magnetic‐resonance‐ and optical spectroscopy; electrochemistry) in combination with state‐of‐the‐art model calculations from first principles. Our long term vision is a control of functionalized metallocorroles and ‐porphyrins supported on technologically relevant surface templates for selective small‐molecule activation.