scholarly journals On the relation between carbonyl stretching frequencies and the donor power of chelating diphosphines in nickel dicarbonyl complexes

2017 ◽  
Vol 19 (13) ◽  
pp. 9028-9038 ◽  
Author(s):  
Marco Fusè ◽  
Isabella Rimoldi ◽  
Edoardo Cesarotti ◽  
Sergio Rampino ◽  
Vincenzo Barone
Keyword(s):  
Bond Formation ◽  
Metal Ligand ◽  
Ligand Bond ◽  
Donor Power

We unravel the mechanisms of chelation-bond formation in nickel dicarbonyl complexes with bidentate phosphines and demonstrate that σ donation drives the carbonyl stretching response to the metal–ligand bond formation.

Thermodynamics of metal-ligand bond formation. XII. Adducts of Monothio-β-diketone complexes with pyridine and bipyridine

1974 ◽  
Vol 27 (6) ◽  
pp. 1351 ◽  
Author(s):  
DR Dakternieks ◽  
DP Graddon
Keyword(s):  
Thermodynamic Data ◽  
Benzene Solution ◽  
Bond Formation ◽  
Enthalpies Of Formation ◽  
Calorimetric Titration ◽  
Metal Ligand ◽  
Ligand Bond

Thermodynamic data are reported for the addition of pyridine and bipyridine in benzene solution to monothio-β-diketone complexes, ML2, of nickel(11), copper(11), zinc(11) and mercury(11). NiL2 gives NiL2(py)2 and NiL(bpy); ZnL2 gives ZnL2(py) and ZnL2(bpy); in both cases the data show that bipyridine is bidentate. CuL2 gives CuL2 (py) and CuL2 (bpy), with almost equal enthalpies of formation, but the higher stability of CuL2(bpy) shows bipyridine is probably bidentate. HgL2 gives HgL2(py) and a reaction with bipyridine which shows that an extremely unstable adduct is formed. All data were obtained by calorimetric titration.

Thermodynamics of metal-ligand bond formation

1977 ◽  
Vol 132 (1) ◽  
pp. 1-7 ◽  
Author(s):  
D.P. Graddon ◽  
J. Mondal
Keyword(s):  
Bond Formation ◽  
Metal Ligand ◽  
Ligand Bond

Thermodynamics of metalligand bond formation

1986 ◽  
Vol 317 (2) ◽  
pp. 153-157 ◽  
Author(s):  
Y. Farhangi ◽  
D.P. Graddon
Keyword(s):  
Bond Formation ◽  
Metal Ligand ◽  
Ligand Bond

Thermodynamics of metal-ligand bond formation. II. Zinc, cadmium, and mercury(II) complexes of o,o-dialkyldithiophosphates

1971 ◽  
Vol 24 (10) ◽  
pp. 2077 ◽  
Author(s):  
DR Dakternieks ◽  
DP Graddon
Keyword(s):  
Metal Atom ◽  
Alkyl Group ◽  
Thermodynamic Data ◽  
Benzene Solution ◽  
Bond Formation ◽  
Free Energies ◽  
Zinc Cadmium ◽  
Metal Ligand ◽  
Ligand Bond

The reactions of 0,O-dialkyldithiophosphato complexes, {(R0)2PSz}zM (M = Zn, Cd, Hg), to form dimers and 1 : 1 and 1 : 2 adducts with pyridine have been studied calorimetrically in benzene solution a t 30�C. While variation of the alkyl group has little effect, variation of the metal atom causes marked changes in both free energies and enthalpies of reaction. Average values of thermodynamic data obtained are as follows (AGOao3 and AH0300 in k J mol-l, AS0a03 in J K-l mol-l) :

Thermodynamics of metal-ligand bond formation. XXV. Addition of bases to Bis[O,O'-diethyl thiomalonato]nickel(II) in various solvents

1977 ◽  
Vol 30 (3) ◽  
pp. 495 ◽  
Author(s):  
L Ang ◽  
DP Graddon ◽  
VAK Ng
Keyword(s):  
Thermodynamic Data ◽  
Driving Force ◽  
Bond Formation ◽  
Adduct Formation ◽  
Calorimetric Measurements ◽  
Carbon Tetra ◽  
Metal Ligand ◽  
Ligand Bond

Thermodynamic data have been obtained from spectroscopic and calorimetric measurements for the addition of pyridine and 4- methylpyridine to bis(O,O?-diethyl thiomalonato)nickel(II), Ni(etm)2, in solution in cyclohexane, benzene, 1,2-dichloroethane, acetonitrile, butan-2-one and carbon tetra-chloride. In each solvent two base molecules add successively, giving Ni(etm)2B then Ni(etm)2B2. There are only small variations in K1 and K2 in different solvents; typically K1 ≈ 200, K2 ≈ 100 l. mol-1, ΔH�1+2 ≈ -65, ΔH�2 ≈ 0 kJ mol-1 at 30�C, but in benzene and cyclohexane ΔH�2 ≈ -25 and in cyclohexane ΔH�1+2 ≈ -100 kJ mol-1. The main driving force for adduct formation is apparently the formation of the first Ni-N bond, which is accompanied by a spin change.

Thermodynamics of metal-ligand bond formation

1975 ◽  
Vol 87 (1) ◽  
pp. 67-82 ◽  
Author(s):  
Y. Farhangi ◽  
D.P. Graddon
Keyword(s):  
Bond Formation ◽  
Metal Ligand ◽  
Ligand Bond

Thermodynamics of metal-ligand bond formation. XXIX. Nickel(II) dialkylmonothiocarbamate complexes

1977 ◽  
Vol 30 (10) ◽  
pp. 2133 ◽  
Author(s):  
DP Graddon ◽  
IA Siddiqi
Keyword(s):  
Absorption Spectra ◽  
High Spin ◽  
Benzene Solution ◽  
Bond Formation ◽  
Molecular Weights ◽  
Metal Ligand ◽  
Ligand Bond

In benzene solution at concentrations below 10-2 M, measurements of molecular weights, absorption spectra and the enthalpies of reaction with bases are all consistent with Ni(SOCNR2)2 (R = Pr or Bu) existing as an equilibrium between low-spin monomeric and high-spin dimeric, probably five-coordinate, species. Enthalpies of dimerization are about -55 kJ (g-atom Ni)-1 and dimerization constants increase from 250 l. mol-1 at about 5�C to 1000 l. mol-1 at 30�C, which shows that the entropy of dimerization is not temperature-invariant. Addition of bidentate bases to the monomer is quantitative with ΔH� about -100 kJ mol-1. Addition of pyridine, 4-methylpyridine or piperidine occurs in two steps, giving high-spin adducts, first five-coordinate NiL2B then six-coordinate NiL2B2 with K1 ≈ K2, ΔH1� ≈ -100 and ΔH2� near zero. Comparisons are made with other low-spin nickel(II) complexes which form high-spin polymers or adducts.

Thermodynamics of metal-ligand bond formation. IX. Trimerization and base addition of Bis(2,6-dimethylheptane-3,5-dionato)nickel(II)

1974 ◽  
Vol 27 (2) ◽  
pp. 407 ◽  
Author(s):  
DP Graddon ◽  
TT Nyein
Keyword(s):  
Equilibrium Constant ◽  
Benzene Solution ◽  
Bond Formation ◽  
Addition Reactions ◽  
Dynamic Data ◽  
Metal Ligand ◽  
Ligand Bond

The equilibrium constant for trimerization of bis(2,6-dimethylheptane-3,5-dionato)nicke1(11) in benzene solution at 30�C has been determined spectrophotometrically, K = 2 x 103 I2 mol-1; the heat of trimerization has been determined calorimetrically, ΔH = -7 kJ (g-atom Ni)1. Thermo- dynamic data have also been obtained for the base addition reactions with pyridine leading to first Ni2L4(py) then NiL2(py)2. Results are compared with those previously obtained for other nickel(11) β-diketone complexes.

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