Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore.
Dalton Trans. 2012 May 21;41(19):5988-94. doi: 10.1039/c2dt12354a. Epub 2012 Apr 5.
A series of Ru(II) mixed-ligand complexes RuBr(2)(PPh(3))(2)(N-AyBzTh) (Ay = prop-2-enyl; BzTh = benzothiazol-2-ylidene) (4), RuBr(OAc)(PPh(3))(N-MeAyBzTh) (5), RuBr(OAc)(PPh(3))(N-MeBnBzTh)(2) (MeBn = 3-methylbut-2-enyl) (6) and RuCl(OAc)(PPh(3))(N-MeBnBzTh) (7) have been synthesized from Ru(OAc)(2)(PPh(3))(2) in one-pot condensation and ligand exchange reactions. X-ray single-crystal diffraction analysis revealed that they are neutral octahedral Ru(II) complexes with one or two N,S-heterocyclic carbene (NSHC) ligands and a coordinated (4, 5 and 7) or dangling (6) olefin arm. The system displays a range of self-selecting structural variations. Entry of the hybrid olefin-NSHC and halide ligands ejects either one (5, 6 and 7) phosphine ligand or keeps both phosphines (4) by replacing the acetate. It is also possible to accommodate two NSHC ligands by keeping the olefin pendant (6). Complexes 5 and 7 are isostructural with all different ligands on the coordination sphere. Complexes 4-6 are active towards transfer hydrosilylation showing good β(Z) selectivity, with the Ru(II) bearing acetate giving higher yields.
一系列 Ru(II) 混配配合物 RuBr(2)(PPh(3))(2)(N-AyBzTh)（Ay=丙烯基；BzTh=苯并噻唑-2-亚基）(4)、RuBr(OAc)(PPh(3))(N-MeAyBzTh)(5)、RuBr(OAc)(PPh(3))(N-MeBnBzTh)(2)（MeBn=3-甲基-2-丁烯基）(6) 和 RuCl(OAc)(PPh(3))(N-MeBnBzTh)(7) 由 Ru(OAc)(2)(PPh(3))(2) 通过一锅法缩合和配体交换反应合成。X 射线单晶衍射分析表明，它们是中性八面体 Ru(II) 配合物，具有一个或两个 N，S-杂环卡宾（NSHC）配体和一个配位的（4、5 和 7）或悬垂的（6）烯烃臂。该体系显示出一系列的自选择结构变化。混合烯烃-NSHC 和卤化物配体的进入会逐出一个（5、6 和 7）膦配体，或者通过取代乙酸根保留两个膦配体（4）。通过保留烯烃悬垂部分（6），也可以容纳两个 NSHC 配体。配合物 5 和 7 在配位球上具有所有不同的配体，是同构的。配合物 4-6 对转移氢化硅烷化反应具有活性，表现出良好的β(Z)选择性，带有乙酸根的 Ru(II) 给出更高的产率。
