近日，印度理工学院马德拉斯分校Sundargopal Ghosh团队报道了二茂铁的无碳类似物[Os(η⁵-B₅H₁₀)₂]。该项研究成果发表在2026年4月23日出版的《科学》杂志上。

合成不含碳的二茂铁类似物一直是无机化学领域的长期目标。

研究组报道了无碳夹心配合物[Os(η⁵-B₅H₁₀)₂]的制备及其晶体学表征，该配合物在结构与成键特性上与二茂铁本质相似。在[Os(η⁵-B₅H₁₀)₂]中，由于桥联B-H-B氢原子以及较大B₅H₁₀环（其中B-H_t为末端B-H键）中弯曲的B-H_t键带来的π分子轨道再杂化，金属-环之间的成键作用显著增强。

这也导致环-环间距异常缩短至3.071埃，并呈现交错构象。此外，还分离出了异构体[Os(η⁵-B₅H₁₀)(η³-B₅H₁₀)]，该异构体具有二茂铁中未知的配位模式。对于[Ru(η⁵-B₅H₁₀)₂]的类似尝试，仅得到[Ru(η⁵-B₅H₁₀)(η³-B₅H₁₀)]。

附：英文原文

Title: [Os(η5-B5H10)2]: A carbon-free analog of ferrocene

Author: Stutee Mohapatra, Suvam Saha, Gaurav Joshi, Urvashi Gupta, Deepak Kumar Patel, Eluvathingal D. Jemmis, Sundargopal Ghosh

Issue&Volume: 2026-04-23

Abstract: The synthesis of a carbon-free analog of ferrocene has been a long-standing goal in inorganic chemistry. We report here the preparation and crystallographic characterization of the carbon-free sandwich complex [Os(η5-B5H10)2], which is qualitatively similar to ferrocene in structure and bonding. The metal-ring bonding is much stronger in [Os(η5-B5H10)2], owing to rehybridization of the π molecular orbitals brought in by the bridging B-H-B hydrogens and the bent B-Ht bonds of the larger B5H10 ring (where B-Ht is the terminal B-H bond). This also leads to an unusually short ring-ring separation of 3.071 angstroms and a staggered conformation. The isomeric [Os(η5-B5H10)(η3-B5H10)], which features a coordination mode unknown for ferrocene, has also been isolated. A similar attempt for [Ru(η5-B5H10)2] resulted only in [Ru(η5-B5H10)(η3-B5H10)].

DOI: aed9192

Source: https://www.science.org/doi/10.1126/science.aed9192