Dinitrogen activation at cyclopentadienyl-phosphine Iron complexes of three different valences Gao-Xiang Wang , Jianhao Yin, Jiapeng Li, Zhu-Bao Yin, Botao Wu, Junnian Wei, Wen-Xiong Zhang and Zhenfeng Xi Peking University, China A series of structurally well-defined iron-dinitrogen complexes (LFe-N 2 ) bearing cyclopentadienyl-phosphine ligands ( L ) were synthesized and revealed by single crystal X-ray structural analysis, IR/Raman spectra, magnetometry, Mössbauer spectroscopy and elemental analysis. The conversion relationship and the change of the spin states among the iron complexes with different valences were studied in detail, showing a series of metal-centered reduction processes (LFe II -N 2 0 -Fe II L → LFe I -N 2 0 -Fe I L → LFe 0 -N 2 0 ). Based on the spectroscopic parameters, the activation degree of the dinitrogen increases while the oxidation state of the iron decreases. DFT calculations of these iron complexes involving the Mayer bond order and NBO charge analysis confirmed our hypothesis. Furthermore, a novel one-pot method of synthesizing diiron-dinitrogen complexes was realized by mixing the potassium salts of ligands (LK) and iron halides without adding any reductants. The diiron(II) dinitrogen complex showed reversible binding of molecular dinitrogen under N 2 or argon atmosphere.
References 1. For selected reviews, see: (a) Li, J. Yin, C. Yu, W.-X. Zhang and Z. Xi. Acta Chim. Sinica., 2017 , 75 , 733. (b) Z.-J. Lv, J. Wei, W.-X. Zhang, P. Chen, D. Deng, Z.-J. Shi and Z. Xi. Natl. Sci. Rev., 2020 , 7 , 1564. 2. (a) G.-X. Wang, J. Yin, J. Li, Z.-B. Yin, W.-X, Zhang and Z. Xi. Chem. Front ., 2019 , 6 , 428. (b) J. Yin, J. Li, G.-X. Wang, Z.-B. Yin, W.-X. Zhang and Z. Xi. J. Am. Chem. Soc ., 2019 , 141 , 4241. (c) J. Li, J. Yin, G.-X. Wang, Z.-B. Yin, W.-X. Zhang and Z. Xi. Chem. Commun ., 2019 , 55 , 9641.-X. Wang, J. Yin, J. Li, Z.-B. Yin, B. Wu, J. Wei, W.-X, Zhang and Z. Xi. CCS Chem., 2021 , 3, 308.
P48
© The Author(s), 2023
Made with FlippingBook Learn more on our blog