Electon-Deficient d- and f-Transition Metal Complexes with Sulfur Ligands

缺电子 d- 和 f- 过渡金属与硫配体的配合物

基本信息

批准号：
02640476
负责人：
TATSUMI Kazuyuki
金额：
$ 1.28万
依托单位：
Osaka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1990
资助国家：
日本
起止时间：
1990 至 1991
项目状态：
已结题

项目摘要

(1)We have isolated variegated sulfide complexes from reactions of Li_2S_x(x=l, 2, 4)with Cp^*TaCl_4(Cp^*=eta^5-C_5Me_5). A common facet of these sulfide complexes is that they possess Li cations bound strongly to sulfur. By taking an advantage of having such lithiums, we found a new route to heteronuclear clusters comprising a common Cp^*TaS_3 unit. For example, [Cp^*TaS_3Li_2(thf)_2]_2 reacts with[RhCl(cod)]_2 to give the TaRh_2 trinuclear complex(Cp^*TaS_3)[Rh(cod)]_2. The structure was found not rigid in a solution, and the fluxional behavior was monitored by the ^1H-NMR signals arising from the olefinic protons in cod ligands. We postulate that the two Rh(cod)fragments migrate below the TaS^3 unit via a 3-coordinate intermediate, during which time each cod ligand switches its coordination site within the Rh(cod)unit,(2)The reaction of[Cp^*TaS_3Li_2(thf)_2]_2 with either(Ph_4P)_2(Fe_4S_4Cl_4), (Ph_4P)(Fe_3(SPh)_3), or(Ph_4P)_2(Fe_2S_2Cl_2)at 50ﾟC in THF gave rise to a formation of … More a Ta_<>2Fe cluster, (Cp^*TaS_3)Fe^<2->. This finding imply a possible dissociation of the iron-sulfur clusters in a solution.(3)In the reaction between Cp^*TaCl_4 and LiS^tBu we observed a stepwise replacement of chloride in with the thiolate. Thus, addition of a THF solution of 2 equiv LiS^tBu afforded Cp^*TaCl_2(S^tBu)_2 while Cp^*TaCl(S^tBu)_2 while Cp^*TaCl(S^tBu)_3 was prepared from the (1 : 3) Cp^*TaCl_4/LiS^tBu reaction system. When the amount of LiS^tBu was increased to 4 equiv, a facile C-S bond repture occurred to give rise to a sulfide complex, Cp^*TaS(S^tBu)_2. The main product of the reaction between Cp^*TaCl_4 and 6-8 equiv of LiS^tBu in THF is again the sulfide complex.(4)We have analyzed the fluydonal behavior of a homoleptic dithiolate complex of uranium[Li_4(dme)_4][U(SCH_2CH_2^S)_4] by ^<>H NMR to find that there are two dynamical processes ; one is a site exchange of sulfur atoms in the dodecahedral US8 coordination sphere, and the other is the conformation change of the USCCS ring. The activation parameters of these processes have been determined. Less

(1)我们从Li_2S_x(x=l, 2, 4)与Cp^*TaCl_4(Cp^*=eta^5-C_5Me_5)的反应中分离出杂色硫化物配合物这些硫化物配合物的一个共同点是它们具有。锂阳离子与硫牢固结合，利用这种锂的优势，我们找到了一条获得包含共同核团簇的新途径。 Cp^*TaS_3 单元例如，[Cp^*TaS_3Li_2(thf)_2]_2 与[RhCl(cod)]_2 反应得到TaRh_2 三核配合物(Cp^*TaS_3)[Rh(cod)]_2。发现溶液中的结构不是刚性的，并且通过烯属质子产生的 ^1H-NMR 信号监测流动行为在 cod 配体中，我们假设两个 Rh(cod) 片段通过 3 配位中间体迁移到 TaS^3 单元下方，在此期间每个 cod 配体在 Rh(cod) 单元内切换其配位位点，(2) [Cp^*TaS_3Li_2(thf)_2]_2 与(Ph_4P)_2(Fe_4S_4Cl_4) 的反应， (Ph_4P)(Fe_3(SPh)_3) 或(Ph_4P)_2(Fe_2S_2Cl_2) 在 50°C 的 THF 中形成…更多 Ta_<>2Fe 簇，(Cp^*TaS_3)Fe^<2 ->. 这一发现意味着溶液中铁-硫簇可能发生解离。(3)我们观察到 Cp^*TaCl_4 和 LiS^tBu 中的氯化物逐步被硫醇盐取代，因此，添加 2 当量 LiS^tBu 的 THF 溶液得到 Cp^*TaCl_2(S^tBu)_2，而 Cp^*TaCl( S^tBu)_2 而 Cp^*TaCl(S^tBu)_3 是由 (1 : 3) 制备的Cp^*TaCl_4/LiS^tBu 反应体系当 LiS^tBu 的量增加到 4 当量时，容易发生 C-S 键断裂，生成硫化物络合物 Cp^*TaS(S^tBu)_2。 Cp^*TaCl_4 与 6-8 当量的 LiS^tBu 在 THF 中反应的主要产物也是硫化物络合物。(4)我们分析了通过 ^<>H NMR 观察铀均配二硫醇络合物[Li_4(dme)_4][U(SCH_2CH_2^S)_4]的 Fluydonal 行为，发现存在两个动力学过程；一个是硫原子在其中的位点交换；十二面体US8配位球，另一个是USCCS环的构象变化，这些过程的激活参数已经确定。