...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Dalton transactions: An international journal of inorganic chemistry >Palladium(II) complexes with highly basic imidazolin-2-imines and their reactivity toward small bio-molecules
【24h】

Palladium(II) complexes with highly basic imidazolin-2-imines and their reactivity toward small bio-molecules

机译：具有高度碱性的咪唑啉-2-亚胺的钯（II）配合物及其对小生物分子的反应性

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

A series of novel Pd(II) complexes with chelating mono(imidazolin-2-imine) and bis(imidazolin-2-imine) ligands were synthesized. The crystal structures of [Pd(DMEAIm(iPr))Cl-2] and [Pd(DPENIm(iPr))Cl-2] were determined by X-ray diffraction analysis. The reactivity of the six Pd(II) complexes, namely, [Pd(en) Cl2], [Pd(EAIm(iPr))Cl-2], [Pd(DMEAIm(iPr))Cl-2], [Pd(DPENIm(iPr))Cl-2], [Pd(BLiPr)Cl-2] and [Pd(DACH(Im(iPr))(2))Cl-2], were investigated. Spectrophotometric acid-base titrations were performed to determine the pK(a) values of the coordinated water molecules in [Pd(en)(H2O)(2)](2+), [Pd(EAIm(iPr))(H2O)(2)](2+), [Pd(DMEAIm(iPr))(H2O)(2)](2+), [Pd(DPENIm(iPr))(H2O)(2)](2+), [Pd(BLiPr)(H2O)(2)](2+) and [Pd(DACH(Im(iPr))(2))(H2O)(2)](2+). The substitution of the chloride ligands in these complexes by TU, L-Met, L-His and Gly was studied under pseudo-first-order conditions as a function of the nucleophile concentration and temperature using stopped-flow techniques; the sulfur-donor nucleophiles have shown better reactivity than nitrogen-donor nucleophiles. The obtained results indicate that there is a clear correlation between the nature of the imidazolin-2-imine ligands and the acid-base characteristics and reactivity of the resulting Pd(II) complexes; the order of reactivity of the investigated Pd(II) complexes is: [Pd(en)Cl-2] > [Pd(EAIm(iPr))Cl-2] > [Pd(DMEAIm(iPr))Cl-2] > [Pd(DPENIm(iPr))Cl-2] > [Pd(BLiPr)Cl-2] > [Pd(DACH(Im(iPr))(2))Cl-2]. The solubility measurements revealed good solubility of the studied imidazolin-2-imine complexes in water, despite the fact that these Pd(II) complexes are neutral complexes. Based on the performed studies, three unusual features of the novel imidazolin-2-imine Pd(II) complexes are observed, that is, good solubility in water, very low reactivity and high pKa values. The coordination geometries around the palladium atoms are distorted square-planar; the [Pd(DMEAIm(iPr))Cl-2] complex displays Pd-N distances of 2.013(2) and 2.076(2) angstrom, while the [Pd(DPENIm(iPr))Cl-2] complex displays similar Pd-N distances of 2.034(4) and 2.038(3) angstrom. The studied systems are of interest because little is known about the substitution behavior of imidazolin-2-imine Pd(II) complexes with bio-molecules under physiological conditions.
机译：合成了一系列具有螯合的单（咪唑啉-2-亚胺）和双（咪唑啉-2-亚胺）配体的新型Pd（II）配合物。通过X射线衍射分析确定[Pd（DMEAIm（iPr））Cl-2]和[Pd（DPENIm（iPr））Cl-2]的晶体结构。六种Pd（II）配合物的反应性，即[Pd（en）Cl2]，[Pd（EAIm（iPr））Cl-2]，[Pd（DMEAIm（iPr））Cl-2]，[Pd（研究了DPENIm（iPr）Cl-2]，[Pd（BLiPr）Cl-2]和[Pd（DACH（Im（iPr））（2））Cl-2]。进行分光光度酸碱滴定，以确定[Pd（en）（H2O）（2）]（2 +），[Pd（EAIm（iPr））（H2O）（ 2）]（2 +），[Pd（DMEAIm（iPr））（H2O）（2）]（2 +），[Pd（DPENIm（iPr））（H2O）（2）]（2 +），[Pd （BLiPr）（H2O）（2）]（2+）和[Pd（DACH（Im（iPr））（2））（H2O）（2）]（2+）。使用止流技术，在拟一级条件下，根据亲核试剂的浓度和温度，研究了TU，L-Met，L-His和Gly对这些络合物中氯化物配体的取代作用。硫供体亲核试剂显示出比氮供体亲核试剂更好的反应性。所得结果表明，咪唑啉-2-亚胺配体的性质与所得Pd（II）配合物的酸碱特性和反应性之间存在明显的相关性。研究的Pd（II）配合物的反应顺序为：[Pd（en）Cl-2]> [Pd（EAIm（iPr））Cl-2]> [Pd（DMEAIm（iPr））Cl-2]> [Pd（DPENIm（iPr））Cl-2]> [Pd（BLiPr）Cl-2]> [Pd（DACH（Im（iPr））（2））Cl-2]。溶解度测量结果表明，所研究的咪唑啉-2-亚胺配合物在水中具有良好的溶解度，尽管这些Pd（II）配合物是中性配合物。基于进行的研究，观察到新型咪唑啉-2-亚胺Pd（II）配合物的三个非同寻常的特征，即在水中的良好溶解性，极低的反应性和较高的pKa值。钯原子周围的配位几何形状是扭曲的方形平面。 [Pd（DMEAIm（iPr））Cl-2]络合物显示Pd-N距离为2.013（2）和2.076（2）埃，而[Pd（DPENIm（iPr））Cl-2]络合物显示相似的Pd-N距离。 N距离为2.034（4）和2.038（3）埃。由于在生理条件下对咪唑啉-2-亚胺Pd（II）配合物与生物分子的取代行为了解甚少，因此研究的系统颇受关注。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号