Complexes of substituted benzothiazoles 4. Nickel(II) complexes of the bidentate benzothiazoles 1,2-bis(2-benzothiazolyl)benzene and 1,2-bis(2-benzothiazolyl)ethane

1982 ◽  
Vol 60 (4) ◽  
pp. 514-520 ◽  
Author(s):  
Laurence Kenneth Thompson ◽  
John Charles Thomas Rendell ◽  
George Charles Wellon
Keyword(s):  
Coordination Chemistry ◽  
Infrared Spectra ◽  
Nickel Complexes ◽  
Magnetic Data ◽  
Octahedral Complex ◽  
Ligand Field ◽  
Tetrahedral Coordination ◽  
Ethylene Bridge ◽  
X Ray ◽  
Square Planar

The nickel coordination chemistry of two potentially bidentate bis-benzothiazole ligands is compared. 1,2-Bis(2-benzothiazolyl)-benzene (OBT), which has an o-phenylene bridge, forms square planar derivatives with NiX2 (X = I, ClO4, BF4), octahedral derivatives with NiX2 (X = NCS, NO3), and five-coordinate derivatives with NiX2 (X = CI, Br). 1,2-Bis(2-benzothiazolyl)ethane (BBTE), which has an ethylene bridge, forms tetrahedral derivatives with NiX2 (X = CI, Br, I) and an octahedral complex with Ni(NO3)2. Although both ligands are capable of tetrahedral coordination about a cobalt centre, the apparent preference of tetrahedral coordination with nickel complexes of BBTE seems unusual. The only difference between the two ligands lies in the bridging group between the benzothiazole rings. Structural assignments are supported by ligand field and infrared spectra, magnetic data, and an X-ray structure of the complex [Ni(BBTE)Br2], which has been shown to have a distorted tetrahedral stereochemistry.

Synthesis and structure of 4-methylpyridine complexes of cobalt(II) and nickel(II) hexafluorophosphate and hexafluoroarsenate

1978 ◽  
Vol 56 (7) ◽  
pp. 985-991 ◽  
Author(s):  
Raymond M. Morrison ◽  
Robert C. Thompson
Keyword(s):  
Magnetic Properties ◽  
Field Strength ◽  
Single Crystal ◽  
Infrared Spectra ◽  
Electronic Spectra ◽  
Preliminary Report ◽  
Ligand Field ◽  
X Ray Diffraction ◽  
X Ray ◽  
Square Planar

The complexes M(4mepy)4A2 and M(H2O)2(4mepy)8A2 (where M is Ni or Co and A is PF6 or AsF6) have been prepared and their electronic spectra and magnetic properties studied. A preliminary report is made of single crystal X-ray diffraction studies on Ni(H2O)2(4mepy)8(PF6)2, Co(H2O)2(4mepy)8(PF6)2, and Co(4mepy)4(PF6)2. All of the complexes have structures involving complex cations and non-coordinated anions, consistent with extremely weak ligating abilities for both PF6− and AsF6−. Cations identified and characterized are the squashed tetrahedral [Co(4mepy)4]2+ ion, the square planar [Ni(4mepy)4]2+ ion, and the tetragonal [Co(4mepy)4((4mepy)2H2O)2]2+and [Ni(4mepy)4((4mepy)2H2O)2]2+ ions. The ligand field strength of 4-methylpyridine is found to be indistinguishable from that of pyridine in these complexes. Infrared spectra are reported and infrared criteria for establishing the presence of non-coordinated anions in PF6− and AsF6− complexes are suggested.

scholarly journals Complex Formation Between Imidazole and Nickel(II) Salts

1974 ◽  
Vol 29 (7-8) ◽  
pp. 527-531 ◽  
Author(s):  
J. C. Jansen ◽  
J. Reedijk
Keyword(s):  
Complex Formation ◽  
Infrared Spectra ◽  
Coordination Compounds ◽  
Tetragonal Symmetry ◽  
Ligand Field ◽  
X Ray ◽  
Square Planar ◽  
Ligand Field Spectra ◽  
Crystal Field Parameters ◽  
Imidazole Compounds

Coordination compounds of formula Ni(Iz)nX2(H2O)m, in which Iz=imidazole, n = 1, 2, 4, 6, m = 0-4, and X = Cl-, Br-, I- and NCS-, are described. The anhydrous compounds are prepared from ethanolic solutions of Iz and nickel(II) salts in stoichiometric amounts in the presence of the dehydrating agent triethylorthoformate. Without this dehydrating agent hydrates are isolated for n = 2,4 and 6 with X = Cl, Br.The compounds were identified by means of infrared spectra (4000-25 cm-1), ligand-field spectra (35000-4000 cm-1) and X-ray powder diagrams. Compounds of formula [Ni(Iz)6]X2 all contain octahedrally coordinated Ni2+, for which the spectrochemical parameters were obtained. Tetragonal Ni2+ ions occur in [Ni(Iz)4X2] in which X = Cl and NCS, and in [Ni(Iz)4(H2O)2]X2 in which X = Cl and Br. These compounds are paramagnetic and the crystal-field parameters for tetragonal symmetry have been calculated. In [Ni(Iz)4]X2 with X = I and Br, the Ni2+ ions are square-planar coordinated with anions in the second coordination sphere, resulting in orange-coloured diamagnetic compounds.Anion-bridged distorted octahedrally coordinated Ni2+ ions probably occur in the compounds of formula Ni(Iz)2X2, in which Iz takes the axial positions. Similar structures are suggested for the mono-imidazole compounds, NiIzX2.

The Coordination Chemistry of Phosphoryl Compounds Containing the — N(CH3)2 Group, Part VIII

1972 ◽  
Vol 27 (7) ◽  
pp. 759-763 ◽  
Author(s):  
M. W. G. De Bolster ◽  
W. L. Groeneveld
Keyword(s):  
Coordination Chemistry ◽  
General Formula ◽  
Ligand Field ◽  
Chemical Analyses ◽  
X Ray ◽  
Physical Measurements ◽  
Ligand Field Spectra ◽  
Chloride Adduct ◽  
Ligand Field Parameters ◽  
Group Part

A number of new solvates and adducts containing bisphenyldimethylaminophosphine oxide is reported. The solvates have the general formula M[(C6H5)2P(O)N(CH3)2]42+(anion-)2, in which M = Mg, Ca, Mn, Fe, Co, Ni, Cu, Zn and Cd, and the anions are ClO4- and BF4-. The adducts have the general formula M[(C6H5)2P(O)N(CH3)2]2Cl2, where M stands for the same series of metals.The compounds are characterized and identified by chemical analyses and physical measurements.Ligand-field and vibrational spectra have been investigated; values for the ligand-field parameters are reported. It is concluded that coordination takes place via the oxygen atom of the ligand.X-ray powder patterns were used in combination with ligand-field spectra to deduce the coordination around the metal ions.The interesting behaviour of the nickel (II) chloride adduct upon heating is discussed and it is shown that both a square pyramidal and a tetrahedral modification exists.

Übergangsmetallkomplexe mit Schwefelliganden, LXXVI Redox- und Additionsreaktionen von Nickelkomplexen mehrzähniger Thioether-Thiolat-Liganden. Röntgenstrukturanalysen von (NMe4)2[Ni(′S2′)2] und [Ni(′S4 – C3′)(PMe3)] / Transition Metal Complexes with Sulfur Ligands, LXXVI Redox and Addition Reactions of Nickel Complexes with Multidentate Thioether-Thiolato Ligands. X-Ray Structure Determinations of (NMe4)2[Ni(′S2′)2] and [Ni(′S4–C3′)(PMe3)]

1991 ◽  
Vol 46 (12) ◽  
pp. 1601-1608 ◽  
Author(s):  
Dieter Sellmann ◽  
Stefan Fünfgelder ◽  
Falk Knoch ◽  
Matthias Moll
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Structure Analysis ◽  
Transition Metal Complexes ◽  
Nickel Complexes ◽  
Addition Reactions ◽  
Coordination Geometry ◽  
X Ray ◽  
Square Planar ◽  
Structure Determinations

In order to elucidate specific properties of nickel sulfur complexes, redox and addition-elimination reactions of [Ni(′OS4')]2, [Ni(′NHS4')]2, [Ni(′S5')], [Ni('S4—C5')], and [Ni('S4—C3')] were investigated ('OS4′ 2' = 2,2'-bis(2-mercaptophenylthio)diethylether(2—), 'NHS4'2- = 2,2'-bis(2-mercaptophenylthio)diethylamine(2—), 'S5'2- = 2,2'-bis(2-mercaptophenylthio)diethylsulfide(2—), 'S4-C5'2- = 1,5-bis(2-mercaptophenylthio)pentane(2—), 'S4—C3'2- = 1,3-bis(2-mercaptophenylthio)propane(2—)).Cyclovoltammetry proves the complexes to be redox inactive between —1.4 and +0.8 V vs. NHE. Above +0.8 V the complexes are irreversibly oxidized, below —1,4 V desalkylation takes place and [Ni(′S,′)2]2- is formed. An X-ray structure analysis was carried out of (NMe4)2[Ni(′S2')2], which shows a planar anion with the Ni center in a nearly perfect square planar coordination. Distances and angles are practically identical to those in the [Ni(′S2')2-] monoanion.The complexes coordinate only phosphines as coligands, but thioether donors simultaneously decoordinate and, dependant of reaction temperature, mono- or trisphosphine complexes are formed. [Ni(′S4—C3')(PMe3)] was characterized by X-ray structure analysis and exhibits a square pyramidal coordination geometry.

Cobalt(II), nickel(II) and copper(II) complexes of some 2'-hydroxychalcones

1980 ◽  
Vol 33 (4) ◽  
pp. 737 ◽  
Author(s):  
M Palaniandavar ◽  
C Natarajan
Keyword(s):  
Infrared Spectra ◽  
Metal Ion ◽  
Magnetic Moments ◽  
Phenyl Group ◽  
Ligand Field ◽  
Square Planar ◽  
Spin Pairing ◽  
Square Configuration ◽  
Electron Sink ◽  
Octahedral Configuration

Metal(II) bis-chelates of the type ML2 [M = CoII, NiII, CuII; L = 2'- hydroxy-5'-X-chalcone where X = H, CH3, Cl] have been prepared and studied. Structures have been assessed by the measurement of magnetic moments, ligand field and infrared spectra and thermal properties. These chelates possess low-spin trans-square-planar configuration and show resistance to adduct formation in contrast to metal(II) chelates of β-diketones, salicylaldehyde, o-hydroxyaryl ketones and esters and o-hydroxy-crotonophenones, which have high-spin octahedral configuration. Extensive conjugation lowers the energy of the π3* orbital which enters into a very strong dπ-π3* interaction leading to spin-pairing. ��� Infrared spectra indicate that the carbonyl group is perturbed only slightly by coordination to metal. A change in metal ion affects v(C=O), v(M-O) and other vibrations and the order of stability, namely, Co ≈ Ni < Cu, inferred from these vibrations is as expected for the low-spin square configuration of the chelates. Introduction of substituents (5'-X) alters only v(M-O) significantly and the order of stability, namely, Cl > CH3 > H, derived from v(M-O) is consistent with Taft's resonance polar parameters of the substituents. All these observations are explained by the electron sink property of the phenyl group.

Fluorinated Alkoxides. Part VIII. Mixed Ligand Complexes of Perfluoropinacol with Ni2+, Pd2+, Pt2+ and Cu2+. Solvation Equilibria between 4- and 5-coordinate Ni2+

1975 ◽  
Vol 53 (6) ◽  
pp. 809-816 ◽  
Author(s):  
W. Stafford Cripps ◽  
Christopher J. Willis
Keyword(s):  
Metal Ion ◽  
Nickel Complexes ◽  
Mixed Ligand ◽  
Ligand Field ◽  
Electronic Effects ◽  
Unusual Behavior ◽  
Planar Structures ◽  
Square Planar ◽  
Phosphorus Containing ◽  
Fluorinated Alkoxides

Perfluoropinacol, (CF3)2C(OH)C(OH)(CF3)2, ionizes by loss of two protons, and the resulting dinegative ion (PFP2−) chelates to Ni2+, Pd2+, Pt2+, and Cu2+. A variety of stable neutral complexes may be isolated if the tetracoordination of the metal ion is completed with two monodentate or one bidentate nitrogen- or phosphorus-containing ligands; square-planar structures are invariably found. The structures of these complexes are contrasted with those of analogous halides, and it is concluded that electronic effects are predominant in determining them, although steric influences may sometimes be important. The ligand field strength of the perfluoropinacolato ion is approximately equal to that of the thiocyanate ion.The nickel complexes Ni(PFP)22− and (PFP)Ni(RNHCH2CH2NHR) react with donor solvents (water, methanol, pyridine, etc.) to give equilibria between four- and five-coordinate solvated species; six-coordinate species are not observed. This unusual behavior is attributed to the steric hindrance imposed by the bulk of the PFP2− ligand.

Coordination chemistry of dimethylgold(III) and methylmercury(II). Synthesis, 1H N.M.R. and structural studies of Poly(pyrazol-1-yl)borate complexes

1983 ◽  
Vol 36 (6) ◽  
pp. 1107 ◽  
Author(s):  
AJ Canty ◽  
NJ Minchin ◽  
JM Patrick ◽  
AH White
Keyword(s):  
Coordination Chemistry ◽  
Variable Temperature ◽  
Gold Atom ◽  
Pyrazole Ring ◽  
Structural Studies ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
X Ray ◽  
Square Planar ◽  
Borate Complexes

Dimethylgold(III) and methylmercury(II) form complexes Me2AuL and MeHgL where L are poly-(pyrazol-1-yl)borate ligands [HB(pz)3]- and [B(pz)4]-. The structure of Me,Au{HB(pz)3} has been determined by single-crystal X-ray diffraction at 295 K and refined by least-squares methods to R 0.056 for 2194 independent 'observed' reflections. This complex has square-planar coordination for the gold atom involving two coordinated pyrazole rings and one uncoordinated ring, in contrast to the isoelectronic cation [Me2Au{(pz)3CH)]+ which has square planar coordination with a weak axial Au . .N interaction. Variable temperature 1H n.m.r. spectra in CD2Cl2 indicate presence of rapid equilibria between pyrazole ring environments at ambient temperature and, for the MeHgII complexes, down to -90�C. For the Me2AuIII complexes spectra at -90�C indicate presence of pyrazole ring environments in ratios 2 : 1 (L = [HB(pz)3]-) and 2 : 1 : 1 (L = [B(pz)4]-). Crystal data for Me2Au{HB(pz)3}: rhombohedral, space group R3c, a 17.98(1) �, α 117.98(5)�, Z 18.

scholarly journals M–H–BR3 and M–Br–BR3 interactions in rhodium and nickel complexes of an ambiphilic phosphine–thioether–borane ligand

2018 ◽  
Vol 96 (5) ◽  
pp. 484-491 ◽  
Author(s):  
Bradley E. Cowie ◽  
David J.H. Emslie
Keyword(s):  
Crystal Structure ◽  
Room Temperature ◽  
Magnetic Measurements ◽  
Nickel Complexes ◽  
Planar Geometry ◽  
Nmr Spectrum ◽  
X Ray ◽  
H Nmr ◽  
Square Planar ◽  
Hydride Ligand

Reaction of [Rh(μ-Cl)(CO)(TXPB)] (1; TXPB = 2,7-di-tert-butyl-5-diphenylboryl-4-diphenylphosphino-9,9-dimethylthioxanthene) with NaBH4 yielded square planar [Rh(μ-H)(CO)(TXPB)] (2) in which the hydride ligand bridges between rhodium and the borane unit of TXPB. The Rh–H, Rh–B, and Rh–Cipso distances are short at 1.84(5), 2.456(6), and 2.568(5) Å, respectively, whereas the B–H bond, 1.59(6) Å, falls at the longer end of the usual range. Compound 2 is compared with the previously reported series of rhodium TXPB complexes: [RhX(CO)(TXPB)] {X = F (3), Cl (1), Br (4), I (5)}. Compound 4 in this series features the only crystallographically characterized example of an M–Br–BR3 interaction, and to expand this area, [NiBr(μ-Br)(TXPB)] (6) was prepared via the reaction of [NiBr2(dme)2] (dme = 1,2-dimethoxyethane) with TXPB. An X-ray crystal structure of light purple 6 revealed a square-planar geometry with a strong B–Br interaction {B–Br = 2.311(6) Å; ∑(C–B–C) = 344.5(7)°}. An 11B NMR chemical shift of 23 ppm was observed for 6, indicating that an appreciable B–Br interaction is maintained in solution. No signals were observed in the 31P{1H} NMR spectrum at room temperature, whereas a broadened 31P signal was observed at −20 °C, evolving into a sharp singlet at −67 °C. This behaviour suggests that at room temperature, square planar 6 exists in equilibrium with a paramagnetic tetrahedral isomer, present at a level below that detectable through Evans magnetic measurements.

scholarly journals Ni(II) complexes with thioether-functionalized silylamide ligands. Synthesis and crystal structures of [Ni{Me2Si(N-C6H4-2-S-t-Bu)2}], [Ni{Ph2Si(N-C6H4-2-SMe)2}] and [Ni{Ph2Si(N-C6H4-2-SPh)2}]

2019 ◽  
Vol 74 (2) ◽  
pp. 233-240 ◽  
Author(s):  
Ralf Albrecht ◽  
Phil Liebing ◽  
Uwe Morgenstern ◽  
Christoph Wagner ◽  
Kurt Merzweiler
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Crystal Structures ◽  
Nickel Complexes ◽  
Subsequent Reaction ◽  
X Ray ◽  
Bond Lengths ◽  
Tetradentate Ligands ◽  
Square Planar ◽  
Structure Determinations

AbstractThioether-functionalized aminosilanes R2Si(NH-C6H4-2-SR′)2 with R=Me, Ph and R′=t-Bu, Me, Ph were synthesized from the corresponding dichlorosilanes R2SiCl2 and lithiated aniline derivatives LiNH-C6H4-2-SR′. Treatment of the functionalized aminosilanes R2Si(NH-C6H4-2-SR′)2 with two eq. of n-BuLi and subsequent reaction with nickel(II) halides NiX2 (X=Cl, Br) or [Ni(acac)2(TMEDA)] led to the formation of the Ni(II) complexes [Ni{R2Si(N-C6H4-2-SR′)2}]. The X-ray single-crystal structure determinations of the nickel complexes revealed that the thioether-functionalized silylamides R2Si(NC6H4-2-SR′)22− act as tetradentate ligands. The nickel atoms exhibit a distorted square-planar coordination with Ni–N and Ni–S bond lengths in the range of 186.4(3)–186.9(2) pm and 217.5(1)–221.5(1) pm, respectively.

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