Xu Fang-Xue, Zhou Yu-Ting, Zhang Cheng-Cheng, Zhang Xin-Yu, Wei Hai-Yan, Wang Xin-Yi
State Key Laboratory of Coordination Chemistry, Collaborative Innovation Center of Advanced Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Jiangsu Key Laboratory of Biofunctional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210023, China.
Inorg Chem. 2023 Sep 25;62(38):15465-15478. doi: 10.1021/acs.inorgchem.3c01803. Epub 2023 Sep 12.
Three new cyano-bridged Fe-Mo complexes assembled from the [Mo(CN)] unit, Fe ions, and three pentadentate NO ligands, namely {[FeH(dapab)][Mo(CN)]}·2HO·3.5MeCN (), [Fe(Hdapb)(HO)][Fe(Hdapb)(HO)][Mo(CN)]·4HO·3MeCN (), and [Fe(Hdapba)(HO)][Mo(CN)]·6HO () (Hdapab = 2,6-diacetylpyridine bis(2-aminobenzoylhydrazone), Hdapb = 2,6-diacetylpyridine bis(benzoylhydrazone), Hdapba = 2,6-diacetylpyridine bis(4-aminobenzoylhydrazone)), have been synthesized and characterized. Single-crystal structure analyses suggest that complex contains a one-dimensional (1D) chain structure where two Fe ions are bridged by the in situ generated [Mo(CN)] unit through two -cyanide groups into trinuclear FeMo clusters that are further linked by the amino of the ligand into an infinite chain. Complexes and are cyano-bridged FeMo trinuclear clusters with two Fe ions connected by the [Mo(CN)] and [Mo(CN)] units, respectively. Direct current magnetic studies confirmed the ferromagnetic interactions between the cyano-bridged Fe and Mo centers and significant easy-axis magnetic anisotropy for all three complexes. Furthermore, complexes exhibit slow magnetic relaxation under a zero dc field, with relaxation barriers of 42.3, 21.6, and 14.4 K, respectively, making them the first examples of cyano-bridged Fe-Mo single-molecule magnets.
通过[Mo(CN)]单元、铁离子和三种五齿NO配体组装得到了三种新型氰基桥联的铁-钼配合物，即{[FeH(dapab)][Mo(CN)]}·2HO·3.5MeCN (), [Fe(Hdapb)(HO)][Fe(Hdapb)(HO)][Mo(CN)]·4HO·3MeCN (), 以及[Fe(Hdapba)(HO)][Mo(CN)]·6HO () (Hdapab = 2,6 - 二乙酰基吡啶双(2 - 氨基苯甲酰腙)，Hdapb = 2,6 - 二乙酰基吡啶双(苯甲酰腙)，Hdapba = 2,6 - 二乙酰基吡啶双(4 - 氨基苯甲酰腙))，并对其进行了表征。单晶结构分析表明，配合物 包含一维(1D)链状结构，其中两个铁离子通过原位生成的[Mo(CN)]单元通过两个氰基桥联形成三核FeMo簇，这些簇进一步通过配体的氨基连接成无限长链。配合物 和 是氰基桥联的FeMo三核簇，分别由[Mo(CN)]和[Mo(CN)]单元连接两个铁离子。直流磁性研究证实了氰基桥联的铁和钼中心之间的铁磁相互作用以及所有三种配合物都具有显著的易轴磁各向异性。此外，配合物 在零直流场下表现出缓慢的磁弛豫，弛豫势垒分别为42.3、21.6和14.4 K，使其成为氰基桥联的铁-钼单分子磁体的首例。
