Medium Ring Complexes. Square-Planar Complexes of Nickel(II) and Copper(II) with 1,5-Diazacyclooctane

1966 ◽  
Vol 5 (8) ◽  
pp. 1416-1419 ◽  
Author(s):  
W. Kenneth Musker ◽  
H. Sakhawat Hussain
1974 ◽  
Vol 52 (20) ◽  
pp. 3454-3458 ◽  
Author(s):  
Gian Carlo Pellacani

Dithiomalonamide (Hdtma) and N,N′-diphenyldithiomalonamide (Hdpma) form diamagnetic square-planar complexes PdL2 and PdL2•2DMF. For these complexes a [PdS4] coordination was suggested by their electronic and i.r. spectra. The splitting orbital parameters, Δ1, indicates that these anionic ligands assume an intermediate position in the spectrochemical series of sulfur donors. These ligands also form Pd(HL)2X2 (X = Cl, Br, I, ClO4) and PdHLX2 (X = Cl, Br, I) complexes in which spectroscopic evidence suggests an S,N bidentate ligand coordination, forming six-membered rings. ν(PdN) and ν(PdS) are tentatively assigned. For Pd(Hdpma)2X2 complexes from the far i.r. and electronic spectra we propose a cis-PdN2S2 configuration. The Δ1 parameters in the six-membered ring Pd(HL)2X2 complexes indicate a ligand strength greater than in the analogous S,N coordinated five-membered ring complexes of dithiooxamides and show an inversion of the order found in Ni(HL)2X2 (HL = Hdtma, Hdpma) complexes. In PdHLX2 complexes the presence of two bands assignable to Vasym(PdX) and Vsym(PdX) supports a cis-halogen configuration.


1971 ◽  
Vol 24 (10) ◽  
pp. 1993 ◽  
Author(s):  
DE Scaife

Nuclear quadrupole resonance for the 35Cl nucleus has been observed in some chloro complexes of divalent copper. Square-planar complexes each show two resonance lines, with the following frequencies (at 77�K): (CH3NH3)2CuCl4, 10.780, 12.157 MHz; (C2H5NH3)2CuCl4, 10.817, 12.074 MHz; (enH2)CuCl4, 10.271, 11.901 MHz; and (C3H7NH3)2CuCl4 at 223�K, 11.290 and 11.781 MHz. NH4CuCl3, containing dimeric Cu2Cl62- units, has resonances, at 77�K, at 11.907, 11.993, and 12.448 MHz. The trigonal pyramidal anion in Co(NH3)6CuCl5 has two resonances at 9.642 and 10.352 MHz at 77�K. ��� These results are compared with previous results for copper chloro complexes, and the implications of covalent bonding are discussed. In particular, it is suggested that the long-bond interaction between units in square-planar complexes amounts to 7-16% of the bonding interaction within the units.


2015 ◽  
Vol 22 (1) ◽  
pp. 124-129 ◽  
Author(s):  
Weiwei Gu ◽  
Hongxin Wang ◽  
Kun Wang

A series of Ni dithiolene complexes Ni[S2C2(CF3)]2n(n= −2, −1, 0) (1,2,3) and a 1-hexene adduct Ni[S2C2(CF3)2]2(C6H12) (4) have been examined by NiK-edge X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine-structure (EXAFS) spectroscopies. Ni XANES for1–3reveals clear pre-edge features and approximately +0.7 eV shift in the NiK-edge position for `one-electron' oxidation. EXAFS simulation shows that the Ni—S bond distances for1,2and3(2.11–2.16 Å) are within the typical values for square planar complexes and decrease by ∼0.022 Å for each `one-electron' oxidation. The changes in NiK-edge energy positions and Ni—S distances are consistent with the `non-innocent' character of the dithiolene ligand. The Ni—C interactions at ∼3.0 Å are analyzed and the multiple-scattering parameters are also determined, leading to a better simulation for the overall EXAFS spectra. The 1-hexene adduct4presents no pre-edge feature, and its NiK-edge position shifts by −0.8 eV in comparison with its starting dithiolene complex3. Consistently, EXAFS also showed that the Ni—S distances in4elongate by ∼0.046 Å in comparison with3. The evidence confirms that the neutral complex is `reduced' upon addition of olefin, presumably by olefin donating the π-electron density to the LUMO of3as suggested by UV/visible spectroscopy in the literature.


2021 ◽  
Vol 41 (1) ◽  
pp. 122-147
Author(s):  
D Palit ◽  
L Dey ◽  
S Rabi ◽  
S Roy ◽  
A Alam ◽  
...  

A series of diastereoisomeric square planar nickel(II) diperchlorate complexes, [Ni(L)](ClO4)2{L= isomeric Me8[14]ane (LAα, LBα or LCα)}undergo axial ligand addition reactions with NO3-, Cl-, Br-, SCN- or ClO4- to yield six coordinate octahedral derivatives [NiL(X)x(Y)y].z(H2O)(X=NO3,Cl, Br or SCN; Y= ClO4; x = 1 or 2; y = 1 or 0 and z = 0, 1 or 2). The products have been characterized on the basis of analytical, spectroscopic, magnetic and conductance data. All the derivatives are unstable in open air except one derivative and revert back to original square planar complexes. Antifungal activities of the ligands and their nickel(II) complexes  have been investigated against some phytopathogenic fungi. The Chittagong Univ. J. Sci. 40(1) : 122-147, 2019


2013 ◽  
Vol 10 (3) ◽  
pp. 650-657
Author(s):  
Baghdad Science Journal

This research involves the preparation of new ligands 1,1,2,2- tetrakis (sodium acetate thio)ethylene(L1) and 1,1,2- tris(sodiumacetatethio) ethylene(L2), through the reaction of disodium thioglycolate) with tetra chloro ethylene or tri chloro ethylene in (1:4) or (1:3) moler ratio . Homodinucliar complexes of general formlu [M2(L1)] and [M2(L2)ClH2O] , when M= Co(II), Ni(II), Cu (II) and Zn(II) also mono nuclear complexes of general formula [M(L2)] . The prepared complexes were characterized using spectral method (UV/Visible/ IR) , metal content analysis , magnetic and atomic measurements . The spectral and magnetic measurement indicats that some complexes have tetrahedral or square planar complexes environtment .


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