A C3 Symmetric Nitrate Complex with a Thiophene-Based Tripodal Receptor
摘要:
A thiophene-based tripodal receptor has been synthesized, and its complexes with nitrate and iodide have been determined by single-crystal X-ray analysis. In the nitrate complex, one nitrate is encapsulated in a selective orientation, forming a C-3 symmetric complex, which is bonded to three protonated secondary amines with six NH center dot center dot center dot O bonds. The anion is coordinated in a plane perpendicular to the principal rotation axis passing through the tertiary nitrogen of the receptor and the nitrogen of the encapsulated nitrate. High-level DFT calculations support the crystallographic results, demonstrating that an adduct with trigonal binding of three oxygen atoms is more stable than that of one oxygen atom of the encapsulate nitrate. On the other hand, in the structure of the iodide complex, all three iodides lie outside the cavity. H-1 NMR titration studies indicate that the receptor forms a 1:1 complex with nitrate yielding a binding constant of K = 315 M-1 in chloroform, showing a moderate selectivity over halides and perchlorate.
具有潜在七足(S 3 N 4)三脚架席夫碱配体的新型Cr,Mo,W和Fe金属配合物:合成,表征和抗菌活性
摘要:
摘要已研究了Cr,Mo,W和Fe金属羰基与潜在的七齿(S 3 N 4)三脚架席夫碱配体(thio)3 tren的反应。Schiff碱(硫代)3 tren已经通过噻吩-2-甲醛与三(2-氨基乙基)胺的缩合制备。Schiff碱及其金属配合物已通过IR,UV-Vis,1 H和13 C NMR光谱,TGA和元素分析进行了表征。根据光谱数据,(硫)3 tren作为潜在的七齿配体与金属中心配位。产品已针对细菌进行了体外测试,金黄色葡萄球菌,大肠杆菌,铜绿假单胞菌和蜡状芽孢杆菌采用圆盘扩散法和微肉汤稀释法,其抗菌活性高于配体。最低的MIC被确定为对蜡状芽孢杆菌的铁复合物,最高的对大肠杆菌的钼复合物。
Some copper(I) and copper(II) complexes of two new potentially heptadentate tripodal Schiff base ligands
作者:Elmer C. Alyea、George Ferguson、Michael Jennings、Li Baolong、Xu Zheng、You Xiaozeng、Liu Shixiong
DOI:10.1016/s0277-5387(00)86779-0
日期:1990.1
Unusual coordination of tripodal NN3SS3 donor ligand with nickel(II): Single crystal X-ray structure of [Ni{H2NCH2CH2N(CH2CH2NCH (C4H3S))2} (CH3CN)(H2O)](PF6)2
作者:Amitava Das、H.C. Bajaj、K. Venkatasubramanian、Mohan M. Bhadbhade
DOI:10.1016/0277-5387(94)00274-i
日期:1995.2
Reaction of Ni(acetate)(2).6H(2)O with a potentially heptentate Schiff base ligand, tris[4-(2-thienyl)-3-aza-3-butenyl]amine [(thiophene),tren], resulted in the formation of an unexpected octahedral Ni-II complex with an NiN4 core and the remaining two coordination sites occupied by solvent molecules; An X-ray crystal structure of the complex established the unusual cleavage at one of the three alpha-imino bonds and revealed that it deviates from the usual mono-capped trigonal prismatic coordination polyhedron designed for this type of complex. The complex molecule has an approximate plane of symmetry(C-s) rather than the three-fold axis (C-3) normally observed for this type of complex and is the first example where the apical 'unique' nitrogen approaches the Ni-II as closely as the other three nitrogens of the ligand.
Nickel(II), Copper(II), and Silver(I) complexes of the thiophene containing ligand tris[4-(2-thienyl)-3-aza-3-butenyl]amine (TTME)
作者:Danielle L. Kay、Lena J. Daumann、Graeme R. Hanson、Lawrence R. Gahan
DOI:10.1016/j.poly.2013.03.030
日期:2013.11
The nickel(II), copper(II), and silver(l) complexes of the ligand tris[4-(2-thienyl)-3-aza-3-butenyl]amine (TIME) have been prepared and characterized. The nickel(II) complex, [Ni(TTME)(NO3)](PF6), is six-coorthe copper(II) complex, [Cu(TTME)(NO3)](PF6), five-coordinate and the silver(I) complex, [Ag(TTME)](PF6)center dot H2O, four-coordinate. The silver(I) complex, unlike the complexes of Ni(II) and Cu(II),exhibits an apical nitrogen to silver distance that is significantly longer than the distance from the metal atom to the equatorial nitrogen donors. [Ag(TTME)](PF6)center dot H2O has the sulfur atoms of the thiophene oriented towards the silver ion in the center of the molecule. The EPR spectrum of the copper(II) complex is typical of tetragonally elongated Cu(II) complexes with the unpaired electron in the d(x2-y2) orbital (g(parallel to) > g(perpendicular to) (2.236 and 2.055, respectively); A(parallel to) >> A(perpendicular to) (172.0 and 10.0, respectively). The fully-decoupled Ag-109 spectrum of [Ag(TTME)](PF6)center dot H2O displays a single positively phased peak (+585.58 ppm). Decoupling of the resonance at 3.80 ppm in the proton NMR allowed the elucidation of the Ag-109-H-1 coupling constant (8.57 Hz). Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved.