Takebayashi Satoshi, Ariai Jama, Gellrich Urs, Kartashov Sergey V, Fayzullin Robert R, Kang Hyung-Been, Yamane Takeshi, Sugisaki Kenji, Sato Kazunobu
Science and Technology Group, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan.
Institute of Organic Chemistry, Justus Liebig University Giessen, Heinrich-Buff-Ring 17, Giessen, D-35392, Germany.
Nat Commun. 2023 Sep 5;14(1):4979. doi: 10.1038/s41467-023-40557-7.
Metallocenes are highly versatile organometallic compounds. The versatility of the metallocenes stems from their ability to stabilize a wide range of formal electron counts. To date, d-block metallocenes with an electron count of up to 20 have been synthesized and utilized in catalysis, sensing, and other fields. However, d-block metallocenes with more than formal 20-electron counts have remained elusive. The synthesis and isolation of such complexes are challenging because the metal-carbon bonds in d-block metallocenes become weaker with increasing deviation from the stable 18-electron configuration. Here, we report the synthesis, isolation, and characterization of a 21-electron cobaltocene derivative. This discovery is based on the ligand design that allows the coordination of an electron pair donor to a 19-electron cobaltocene derivative while maintaining the cobalt-carbon bonds, a previously unexplored synthetic approach. Furthermore, we elucidate the origin of the stability, redox chemistry, and spin state of the 21-electron complex. This study reveals a synthetic method, structure, chemical bonding, and properties of the 21-electron metallocene derivative that expands our conceptual understanding of d-block metallocene chemistry. We expect that this report will open up previously unexplored synthetic possibilities in d-block transition metal chemistry, including the fields of catalysis and materials chemistry.
金属茂是用途极为广泛的有机金属化合物。金属茂的多功能性源于它们能够稳定多种形式的电子数。迄今为止，已合成了电子数高达20的d区金属茂，并将其用于催化、传感及其他领域。然而，电子数超过形式上20个电子的d区金属茂仍然难以获得。此类配合物的合成与分离具有挑战性，因为d区金属茂中的金属-碳键随着与稳定的18电子构型偏差的增加而变弱。在此，我们报告了一种21电子钴茂衍生物的合成、分离及表征。这一发现基于一种配体设计，该设计允许电子对供体与19电子钴茂衍生物配位，同时保持钴-碳键，这是一种此前未被探索的合成方法。此外，我们阐明了21电子配合物稳定性、氧化还原化学及自旋态的起源。这项研究揭示了一种21电子金属茂衍生物的合成方法、结构、化学键及性质，拓展了我们对d区金属茂化学的概念性理解。我们预计本报告将开启d区过渡金属化学中此前未被探索的合成可能性领域，包括催化和材料化学领域。
