Five-Coordinate Iridium(III) Complex with DeltaLambda Chirality
Five-Coordinate Iridium(III) Complex with DeltaLambda Chirality
复制标题
具有 DeltaLambda 手性的五配位铱 (III) 配合物
DOI：
10.1039/d1dt01960k
复制
发表时间：
2021
影响因子：
4
通讯作者：
H. Sato
中科院分区：
文献类型：
--
作者：
K. Takimoto;Y. Watanabe;J. Yoshida;H. Sato
通过铱（III）与2-BubzqH以1：2的摩尔比反应，得到配位不饱和双螯合铱（III）配合物[Ir（2-Bubzq）2Cl]（2-BubzqH = 2-丁基苯并[h]喹啉），记作配合物1。 结果与通常认为的在相应条件下形成氯桥二聚体[Ir（L）2Cl]2（L =双螯合配体）的观点相反。单晶X-射线衍射结构分析表明配合物1具有畸变四方锥构型的五配位几何构型。在手性柱上通过色谱法测量络合物1的光学拆分，得到Δ和Λ作为对映体。通过振动圆二色性测量证实，拆分的对映体在CDCl 3中对外消旋足够稳定。配合物1与CO反应生成[Ir（2-Bubzq）2（CO）Cl]，与1，10-邻菲咯啉反应生成[Ir（2-Bubzq）2（phen）]Cl，反应时间为1分钟，其绝对构型（ΔΛ手性）保持不变。
The coordinatively unsaturated bis-chelated iridium(III) complex, [Ir(2-Bubzq)2Cl] (2-BubzqH = 2-butyl-benzo[h]quinoline), denoted as complex 1, was obtained by reacting iridium(III) trichloride with 2-BubzqH in a 1 : 2 molar ratio. The results were in contrast to the common view that a chlorine-bridged dimer, [Ir(L)2Cl]2 (L = bis-chelate ligand), is formed under the corresponding conditions. A single-crystal X-ray diffraction structural analysis revealed that complex 1 has a five-coordinate geometry with a distorted square pyramidal configuration. The optical resolution of complex 1 was measured chromatographically on a chiral column, yielding Δ and Λ as enantiomers. The resolved enantiomers were stable enough against racemization in CDCl3 as confirmed by the vibrational circular dichroism measurements. Complex 1 reacted with carbon monoxide (CO) to give [Ir(2-Bubzq)2(CO)Cl] and with 1,10-phenanthroline (phen) to give [Ir(2-Bubzq)2(phen)]Cl within a minute with its absolute configuration (ΔΛ chirality) maintained.