系列Mo-Cu(Ag,Au)-Se簇合物的95Mo和31P NMR研究

报道了含硬币金属和四硒代钼酸盐的异金属硒簇合物的⁹⁵Mo NMR研究结果和含膦配体Mo(W)-Cu(Ag,Au)-Se配合物的³¹P NMR谱学性能。发现不同硬币金属对⁹⁵Mo核的化学屏蔽效应顺序为Au > Cu > Ag;对系列Mo-Cu-Se化合物的⁹⁵Mo NMR研究结果表明:⁹⁵Mo NMR的化学位移和线宽不仅与配位的Cu原子数目有关,而且对结构的变化特别敏感;MoSe₄]^2-离子的相对四个方向被Cu⁺配位后,其Mo核的屏蔽基本饱和;外围配体对⁹⁵Mo NMR数据影响甚微。同时还用动态⁹⁵Mo NMR谱技术跟踪配体的取代反应和从MoCu₄到MoCu₁₀核的簇骼转变过程。此外,还讨论了这些化合物在不同构型之间,同一构型不同金属中心和不同配体基团的³¹P NMR化学位移的变化特征。

\ 95 Mo AND\ 31 P NMR STUDIES ON SERIES OF\ Mo-Cu(Ag,Au)-Se CLUSTER COMPOUNDS

This paper reports the\ 95 Mo and\ 31 P NMR results of a series of heterometallic cluster compounds containing coinage metal and tetraselenomolybdate. The investigation results indicate that\ 95 Mo NMR chemical shifts and linewidths are not only related to the number of coordination of Cu atoms, but also very sensitive to structural variations. The\ 95 Mo NMR shielding effect is mainly caused by the coiage metal atoms in the tetraselenomolybdate system and the shielding order is Au>Cu>Ag. The saturation of Mo nucleus shielding effect from the coordination of MoSe 4 moiety by four Cu atoms and very little influence on\ 95 Mo nucleus from the outsphere ligands are observed. Additionally, kinetic\ 95 Mo NMR technique was used to monitor ligand substitution reactions and cluster skeleton transformation processes from MoCu 4 to MoCu 10 cores. A variety of characteristics of the\ 31 P NMR chemical shifts of Mo(W)-Cu(Ag,Au)-Se compounds among different structural types are also discussed.