Zhang Xian-Ming, Jiang Tao, Wu Hai-Shun, Zeng Ming-Hua
School of Chemistry & Material Science, Shanxi Normal University, Linfen 041004, P. R. China.
Inorg Chem. 2009 May 18;48(10):4536-41. doi: 10.1021/ic9002912.
Solvothermal treatment of a mixture of Co(OAc)(2), NaN(3), NaN(CN)(2), HF, MeCN, and H(2)O generated an AlB(2)-like metal-organic framework, namely, [{(Co(3)F)(3)(trta)(2)(H(2)O)(9)}{Co(Hbta)(3)}(2)].11H(2)O (1) (H(3)trta = N,N,N-tris-tetrazol-5-yl-amine; H(3)bta = N,N-bis-tetrazol-5-yl-amine), in which supertrianglar supramolecular building blocks (SBBs) {(Co(3)F)(3)(trta)(2)} act as 12-connected nodes of hexagonal prisms. The unprecedented ligand N,N,N-tris-tetrazol-5-yl-amine is in situ generated via metal-assisted reactions of NaN(CN)(2), MeCN, and NaN(3), and a possible mechanism involves both 1,3-dipolar cycloaddition and nucleophilic addition. The F-centered Co(3) triangles are bridged by trta groups to result in supertriangular {(Co(3)F)(3)(trta)(2)} SBBs that are further arranged in a frustrated triangular lattice. The long-range ordering temperature is reduced to 4.8 K due to strong spin frustration.
对Co(OAc)₂、NaN₃、NaN(CN)₂、HF、MeCN和H₂O的混合物进行溶剂热处理，生成了一种类AlB₂金属有机骨架，即[{(Co₃F)₃(trta)₂(H₂O)₉}{Co(Hbta)₃}₂]·11H₂O (1)（H₃trta = N,N,N-三-四唑-5-基胺；H₃bta = N,N-双-四唑-5-基胺），其中超三角形超分子结构单元（SBBs）{(Co₃F)₃(trta)₂}作为六棱柱的12连接节点。前所未有的配体N,N,N-三-四唑-5-基胺通过NaN(CN)₂、MeCN和NaN₃的金属辅助反应原位生成，一种可能的机制涉及1,3-偶极环加成和亲核加成。以F为中心的Co₃三角形由trta基团桥连，形成超三角形{(Co₃F)₃(trta)₂} SBBs，它们进一步排列成受挫三角形晶格。由于强烈的自旋受挫，长程有序温度降至4.8 K。
