过渡金属与新型硝基酚臂式氮杂18-冠-6配位性能的研究  

Transition Metal Ions Complexation Properties of Tetranitrophenols-armed Aza-18-crown-6

作　　者：张强[1] 高生华[1] 

机构地区：[1]内蒙古师范大学化学与环境科学学院,呼和浩特010022

出　　处：《无机化学学报》2008年第4期565-570,共6页Chinese Journal of Inorganic Chemistry

基　　金：内蒙古自然科学基金(No200508010212;200607010207)资助项目

摘　　要：合成并表征了1,10-二氧-4,7,13,16-四氮杂18-冠-6(1)母体及其四取代硝基酚臂式衍生物(2)。在H2O-DMSO(V/V=1/4)混合溶剂中用UV-Vis光谱法对冠醚2与H+、Mn2+、Co2+、Ni2+、Cu2+、Zn2+、Cd2+和Hg2+离子的键合行为进行了研究,并测定了配位稳定常数。结果表明,当冠醚2处在pH值小于7.96的体系中时,其仅有316nm左右的吸收峰;当pH值大于7.96时,在400nm左右产生新的吸收峰,而且其峰位波长和强度随溶液的碱性增强逐渐增大。在冠醚2体系中有过渡金属离子存在时,冠醚在400nm左右的吸收峰发生紫移,强度也有显著的变化,证实了在大于一定pH值的环境中过渡金属与冠醚2可形成配合物。稳定常数的测定表明,冠醚2对Mn2+离子有明显的选择性,与Co2+、Ni2+、Cu2+、Zn2+的配位能力依次有所增强,与Cd2+和Hg2+离子的配位稳定性较小。The parent azacrown ether 1,10 -dioxa-4,7,13,16-tetraaza- 18-crown-6 （1） and its derivative 4,7,13,16- tetra（2-hydroxy-5-nitrobenzyl）- 1,10-dioxa-4,7,13,16-tetraaza- 18-crown-6 （2） were synthesized and characterized via elemental analysis and ^1H NMR spectroscopy. The cation binding behavior of 2 with H^＋, Mn^2＋, Co^2＋, Ni^2＋, Cu^2＋, Zn^2＋, Cd^2＋ and Hg^2＋ was evaluated by UV-Vis method in H2O-DMSO （V/V=1/4） mixed solvent, and the stability constants of the complexes were determined. The results indicate that azacrown ether 2 has strong absorption peak alone in the vicinity of 316 nm at pH〈7.96. While pH〉7.96 in the system, a new absorption band can be observed around 400 nm which is probably a charge transfer band, and its peak position is shifted toward longer wavelength, the absorption intensity is increased gradually with increasing pH value. The peak position of 2 around 400 nm is shifted appreciably toward shorter wavelength when a transition metal ion addition to 2. Thus the formation of the complex is verified at a range of pH values （for example Ni^2＋, 5.6〈pH〈12.72）. The stability constants of the complexes obtained shows that 2 selectively binds Mn^2＋ over other transition metals. The ligand also forms more stable complexes with Co^2＋, Ni^2＋, Cu^2＋ and Zn^2＋ than with Cd^2＋ and Hg^2＋.

关 键 词：四硝基酚臂式氮杂18-冠-6 合成 过渡金属离子 紫外可见光谱法 配位性能 

分 类 号：O614.711[理学—无机化学] O614.81[理学—化学]