Template synthesis of square-planar nickel(II) and copper(III) complexes based on hydrazide ligands

1998 ◽  
pp. 3269-3274 ◽  
Author(s):  
Igor O. Fritsky ◽  
Henryk Kozłowski ◽  
Peter J. Sadler ◽  
Oksana P. Yefetova ◽  
Jolanta Śwątek-Kozłowska ◽  
...  
Keyword(s):  
Template Synthesis ◽  
Square Planar

Platinum(II) Template Synthesis of a Pendant-Arm Macrocycle

1998 ◽  
Vol 51 (9) ◽  
pp. 871 ◽  
Author(s):  
Hong Xiao ◽  
Geoffrey A. Lawrance ◽  
Trevor W. Hambley
Keyword(s):  
Crystal Structure ◽  
Template Synthesis ◽  
Crystal Structure Analysis ◽  
Macrocyclic Complex ◽  
Triclinic Space Group ◽  
X Ray ◽  
Pendant Arm ◽  
Major Isomer ◽  
Square Planar ◽  
R Value

Platinum(II)-directed condensation of ethane-1,2-diamine with nitroethane and formaldehyde yields the colourless macrocyclic complex (trans-6,13-dimethyl-6,13-dinitro-1,4,8,11-tetraazacyclotetradecane)plat- inum(II), [Pt(1)]2+, in good yield. This parallels chemistry reported earlier around other triad members nickel(II) and palladium(II). The pendant nitro groups in the major isomer are disposed on opposite sides of the macrocycle in a trans geometry, as confirmed by the X-ray crystal structure analysis of [Pt(1)] (ClO4)2, which crystallizes in the triclinic space group P-1, a 8·041(4), b 8·482(4), c 9·443(3) Å, α 69·44(3), β 67·66(4), γ 71·73(4)°,Z1, and was refined to an R value of 0·027 on 1920 F. The platinum ion lies in a square planar environment of four nitrogen donors, with typical Pt–N distances; comparisons between the platinum(II) and palladium(II) complexes of (1) and its analogue (2), with diammonio groups in place of dinitro groups, are discussed

Crystal chemistry of high-Tc superconductors

1990 ◽  
Vol 48 (4) ◽  
pp. 1118-1119
Author(s):  
Maryvonne Hervieu
Keyword(s):  
Oxygen Deficiency ◽  
Large Family ◽  
Copper Oxides ◽  
High Tc Superconductors ◽  
High Tc ◽  
Single Mechanism ◽  
Square Planar ◽  
History Of ◽  
Bismuth Cuprates ◽  
New Compounds

Four years after the discovery of superconductivity at high temperature in the Ba-La-Cu-O system, more than thirty new compounds have been synthesized, which can be classified in six series of copper oxides: La2CuO4 - type oxides, bismuth cuprates, YBa2Cu3O7 family, thallium cuprates, lead cuprates and Nd2CuO4 - type oxides. Despite their quite different specific natures, close relationships allow their structures to be simply described through a single mechanism. The fifth first families can indeed be described as intergrowths of multiple oxygen deficient perovskite slabs with multiple rock salt-type slabs, according to the representation [ACuO3-x]m [AO]n.The n and m values are integer in the parent structures, n varying from 0 to 3 and m from 1 to 4; every member of this large family can thus be symbolized by [m,n]. The oxygen deficient character of the perovskite slabs involves the existence or the co-existence of several types of copper environment: octahedral, pyramidal and square planar.Both mechanisms, oxygen deficiency and intergrowth, are well known to give rise easily to nonstoichiometry phenomena. Numerous and various phenomena have actually been characterized in these cuprates, strongly depending on the thermal history of the samples.

New Platinum (II) Ternary Complexes of Formamidine and Pyrophosphate: Synthesis, Characterization and DFT Calculations and In vitro Cytotoxicity

2020 ◽  
Vol 23 (7) ◽  
pp. 611-623
Author(s):  
Ahmed A. Soliman ◽  
Fawzy A. Attaby ◽  
Othman I. Alajrawy ◽  
Azza A.A. Abou-hussein ◽  
Wolfgang Linert
Keyword(s):  
Cell Line ◽  
Cancer Cell ◽  
Theoretical Calculations ◽  
Thermal Analyses ◽  
Cancer Cell Line ◽  
Cellular Growth ◽  
Planar Geometry ◽  
Square Planar ◽  
Vis Spectroscopy

Aim and Objective: Platinum (II) and platinum (IV) of pyrophosphate complexes have been prepared and characterized to discover their potential as antitumor drugs. This study was conducted to prepare and characterize new ternary platinum (II) complexes with formamidine and pyrophosphate as an antitumor candidate. Materials and Methods: The complexes have been characterized by mass, infrared, UV-Vis. spectroscopy, elemental analysis, magnetic susceptibility, thermal analyses, and theoretical calculations. They have been tested for their cytotoxicity, which was carried out using the fastcolorimetric assay for cellular growth and survival against MCF-7 (breast cancer cell line), HCT- 116 (colon carcinoma cell line), and HepG-2 (hepatocellular cancer cell line). Results: All complexes are diamagnetic, and the electronic spectral data displayed the bands due to square planar Pt(II) complexes. The optimized complexes structures (1-4) indicated a distorted square planar geometry where O-Pt-O and N-Pt-N bond angles were 82.04°-96.44°, respectively. Conclusion: The complexes showed noticeable cytotoxicity and are considered as promising antitumor candidates for further applications.

Structure of the complexes of ethylenediphosphinetetraacetic acid in solution

1985 ◽  
Vol 50 (2) ◽  
pp. 445-453 ◽  
Author(s):  
Jana Podlahová ◽  
Josef Šilha ◽  
Jaroslav Podlaha
Keyword(s):  
Metal Ion ◽  
Carboxyl Groups ◽  
Complex Solution ◽  
Square Planar ◽  
Weak Complexes ◽  
Carboxylic Groups ◽  
Uv Visible ◽  
The Stability ◽  
Tetrahedral Complexes ◽  
Free Carboxyl

Ethylenediphosphinetetraacetic acid is bonded to metal ions in aqueous solutions in four ways, depending on the type of metal ion: 1) through an ionic bond of the carboxylic groups to form weak complexes with a metal:ligand ratio of 1 : 1 (Ca(II), Mn(II), Zn(II), Pb(II), La(III)); 2) through type 1) bond with contributions from weak interaction with the phosphorus (Cd(II)); 3) through coordination of the ligand as a monodentate P-donor with the free carboxyl groups with formation of 2 : 1 and 1 : 1 complexes (Cu(I), Ag(I)); 4) through formation of square planar or, for Hg(II), tetrahedral complexes with a ratio of 1 : 2 with the ligand as a bidentate PP-donor with the free carboxyl groups (Fe(II), Co(II), Ni(II), Pd(II), Pt(II)). On acidification of the complex solution, the first two protons are bonded to the carboxyl groups. The behaviour during further protonation depends on the type of complex: in complexes of types 1) and 2) phosphorus is protonated and the complex dissociates; in complexes of types 3) and 4) the free carboxyl groups are protonated and the phosphorus-metal bond remains intact. The results are based on correlation of the stability constants, UV-visible, infrared, 1H and 31P NMR spectra and magnetic susceptibilities of the complexes in aqueous solution.

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