Structural Regularities of the Transition Metal Complexes Containing o-Benzenedithiol (H_2bdt)——Synthesis and Structure of Fe_3(bdt)_3(PBu_3~n)_3

Complex Fe_3(bdt)_3(PBu_3~n)_3 was synthesized in the presence of PBu_3~n and the structural regularities in a series of transition metal complexes containing bdtH_2 ligand were summarized. The title complex crystallizes in the triclinic space group P-, Mr=1195.19, cell parameters: a=13.283(3), b=20.115(5), c=13.156(3), (?)=90.33(2), β= 116.47 (1), γ=92.19(2)°, V=3143.5(2.7)~3, Z=2, d_c=1.26g/cm^3. The structure was solved by direct methods from 4122 unique reflections with I>4σ(I) and reached the final convergence factor of R(Rw) = 0.053 (0.060). The complex exhibits strong paramagnetism.

邻苯二硫酚桥联双核双氮过渡金属配合物N—N键活化规律的理论研究

采用密度泛函理论方法研究了具有仿生固氮结构的两类化合物[Cp＊Fe（μ-η^2η^2bdt）（μ-η^1η^1Me N=NMe）Fe Cp＊]以及[Cp＊Fe（μ-SEt）2（μ-η^1η^1Me N=NMe）Fe Cp＊]的90种不同结构,调变过渡金属中心,研究不同自旋态下（单重态和三重态）具有side-on或end-on配位键型的双核双氮过渡金属配合物,基于计算结果分析了BDT（邻苯二硫酚）和乙基类型配体的不同过渡金属配合物活化双氮的程度.研究结果表明,N—N键活化程度与配合物过渡金属中心所在周期存在密切关系,更高周期对双氮的活化程度更高,同周期金属过渡金属配合物对N—N键的活化程度从第四副族至第八族呈现折线型下降,同时,过渡金属中心的外层价电子数的奇偶性对双氮的活化程度具有一定影响.此外,side-on键型对双氮的活化程度要高于end-on键型,具有不同基团的同种骨架配体对N—N键的活化能力没有明显区别。