Complex Formation of Cobalt(II) and Nickel(II) with 2-Hydroxypropylene-1,3-diamine-N,N,N',N'-tetraacetic Acid

The complex-formation equilibria of 2-hydroxypropylene-1,3-diamine-N,N,N',N'-tetraacetic acid (H₄L) with Co^{2 +} and Ni^{2 +} ions were studied. The stability constants of the complexes CoL^{2 -}, CoHL^-, NiL^{2 -}, and NiHL^- were estimated; the resulting data were compared with respective data for related compounds.     

Crystal structure of (2,2'-bipyridine-N,N)(2,2',2'-triaminotriethylamine-N,N',N',N')nickel(II) diperchlorate.

An X-ray structure determination shows that the Ni(II) ion is a distorted six-coordinated octahedron by four nitrogen atoms of the tetradentate tren ligand constituting the equatorial square base, and by two nitrogen atoms of the bidentate bpy ligand in a cis position. The two six-membered rings of bpy are coplanar and almost pararell. The tetradentate ligand consists of three five-membered chelate rings in gauche coformations. The Ni-N(tren) bond lengths of this complex are almost equivalent to the reported values.     

Crystal structure of (1,10-phenanthroline-N,N')(1,4,7,10-tetraazacyclododecane-N,N',N",N"')nickel(II) diperchlorate.

The crystal structure of the title compound, [Ni(C8H20N4)(C12H8N2)](ClO4)2, has been determined by X-ray diffraction. The Ni(II) ion is six coordinated with four nitrogen atoms of the tetradentate macrocyclic ligand and two nitrogen atoms of the bidentate ligand in a distorted octahedron geometry. The folded tetradentate macrocyclic ligand adopts a configuration having four five-membered chelate rings in distorted eclipsed conformations. The four hydrogen atoms of the amine groups of the macrocyclic ligand are on the same side towards the bidentate ligand.     

Formation of dinuclear copper(II) complex with N,N,N',N'-tetrakis(2-pyridylmethyl)-1,2-ethanediamine in aqueous solution

The polynuclear complexation of divalent 3d transition metal cations with N,N,N',N'-tetrakis(2-pyridylmethyl)-1,2-ethanediamine (tpen) in aqueous solution was investigated. It was found that copper(II) forms a dinuclear complex with tpen in an aqueous solution containing chloride. The composition of the complex was determined as Cu(2)Cl(2)(tpen)(2+). Furthermore, the stability constant of the complex was determined and its structure was postulated to be (mu-Cl)(2).     

N,N,N',N'-四[(二苯基膦)甲基]乙二胺钯配合物催化Heck反应研究

以乙二胺为骨架的含氮四膦配体N’NN,N',N'-四[(二苯基膦)甲基]乙二胺和钯组成的催化体系用于丙烯酸酯和芳卤的Heck反应,该催化体系对许多卤代芳烃,尤其含吸电基的溴代芳烃显示了良好的催化活性.对活化底物对溴苯甲醛,即使底物与催化剂的物质的量比达到1000000,其转化率也能达到96％;催化非活化溴代芳烃对溴苯甲醚以及难以反应的氯代芳烃,在Pd含量为0.1 mol％时同样表现出优良催化性能.     

Polarographic investigation of Cu(II) complexes with N,N,N',N'-tetrakis-(2-hydroxypropyl)-ethylenediamine

During investigation of the formation of Cu(2+) ion complexes with N,N,N',N'-tetrakis-(2-hydroxypropyl)-ethylenediamine (Quadrol-Q) by means of constant current polarography (20 degrees C, ionic strength J = 3 mol l(-1)), the possibility of the formation of two complex compounds; CuQ(2+) and CuQ(2+)(2), was shown within the pH range from 6 to 8. The logarithms of the stability constants for these compounds are 10.6 +/- 0.5 and 14.6 +/- 0.4 respectively. Cu(II) complexation increases sharply when the pH increases from 8 to 10. It was shown that the data at a pH of greater than 10 are in accordance with the existence of the hydroxy complexes CuQ(OH)(2) and CuQ(2)(OH)(2), the logarithms of the stability constants being 26.9 +/- 0.5 and 29.1 +/- 0.3.