Willem L. Driessen

Leiden University, Leyden, South Holland, Netherlands

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Publications (198)256.35 Total impact

  • Willem L. Driessen
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    ABSTRACT: Procedures are described involving the condensation of l-(hydroxymethyl)pyrazole (1a) and l-(hydroxymethyl)-3,5-dimethylpyrazole (1b) with the following amines (products given in parentheses): ethylamine (2a and 2b), aniline (3a and 3b), N,N′-dimethyl- l,2-ethanediamine (4a and 4b), 1,2-ethanediamine (6a and 6b), diethylenetriamine (7a and 7b), triethylenetetramine (8a and 8b) and ammonia (9a and 9b). All amine hydrogens are completely substituted by pyrazol-1-ylmethyl groups (compounds 2a-9a) or (3,5-dimethylpyrazol-1-yl)methyl groups (compounds 2b-9b with yields being better than 90%.
    Recueil des Travaux Chimiques des Pays-Bas. 09/2010; 101(12):441 - 443.
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    ABSTRACT: Seven new complexes are reported with nitrobenzene as the ligand, viz. [M(C6H5NO2)6]2+[SbCl6]2− with M is Mg(II), Ca(II), Mn(II), Fe(II), Co(II), Ni(II), and Zn(II).No shift in the NO stretching frequencies has been observed. The NO2 out of plane bending vibration shifts to higher frequencies dependent on the metal ions.Investigation of ligand field spectra indicates the presence of octahedral species M(nitrobenzene)62+ in the solid compounds. Values for Dq and B for the Co and Ni compounds are reported.
    Recueil des Travaux Chimiques des Pays-Bas. 09/2010; 89(12):1271 - 1275.
  • W. L. Driessen, W. L. Groeneveld
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    ABSTRACT: A series of new complexes is reported with acetone as the ligand: viz. [M(CH3COCH3)62+][A−]2 where M is Mg(II), Ca(II), Sr(II), Mn(II), Fe(II), Co(II), Ni(II), and Zn(II); and A− is FeCl−4 and InCl−4.In the complexes, the carbonyl vibration is shifted to lower frequencies and the CO bending, the CO deformation, and the CCC deformation vibrations are shifted to higher frequencies with regard to the vibrations in the free ligand. The magnitudes of the shifts are dependent on the metal ions. In the far infrared a metal-dependent absorption band appears, which is attributed to the metal-ligand stretching vibration.Investigation of ligand field spectra indicates the presence of octahedral species M(acetone)62+ in the solid compounds. Values for Dq and B′ are reported and the ligand is placed in the spectrochemical and nephelauxetic series.
    Recueil des Travaux Chimiques des Pays-Bas. 09/2010; 88(8):977 - 988.
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    ABSTRACT: The didentate N,O donor ligand 1-(2-hydroxyethyl)-3,5-dimethylpyrazole (N-hed) renders two kinds of coordination compounds, viz. [M(N-hed)2(NO3)2] with M=Co, Ni, Cu, and Zn, [Ni(N-hed)2(NCS)2], and [Cu(N-hed)2Cl2] in which the ligand is neutral, and [Cu(N-oed)X]2 with X=Cl, Br, and NO3 in which the ligand N-hed is in its deprotonated form, viz. 1-(2-oxidoethyl)-3,5-dimethylpyrazole (N-oed).The crystal structure of [Cu(N-hed)2(NO3)2] shows it to be mononuclear, with the copper ion at a centre of symmetry. Monoclinic, space group P21/c, a = 7.8176(8), b = 14.93(2), c = 8.4076(8) Å, β = 92.62(2)°, Z = 2; R = 0.036 (Rw = 0.038) for 2132 significant reflections. The copper(II) ion is in a tetragonal-distorted, elongated-octahedral environment of two trans pyrazole nitrogen atoms at 1.974(2) Å, two trans hydroxyl oxygen atoms at 1.991(2) Å, and two trans oxygen atoms of monodentate coordinated nitrate anions at 2.561(2) Å. The structure is stabilized by strong intramolecular hydrogen bonds between the hydroxyl group of the coordinated ligand and an oxygen atom of the coordinated nitrate ion with a short O-O distance of 2.599(2) Å. The metal ions in the compounds [M(N-hed)2X2] are octahedrally surrounded by two nitrogen and two oxygen atoms of the ligand and by two anion donor atoms (respectively O, N, or Cl).The crystal structure of [Cu(N-oed)Br]2 shows it to be dinuclear. Triclinic, space group P2/1, a = 4.5213(6), b = 8.484(1), c = 13.052(7) Å, α = 81.50(3), β = 85.79(4), γ = 77.79(2)°, Z = 1, R = 0.148 (Rw = 0.224) for 1534 reflections. The copper ions are bridged by two oxo atoms of the deprotonated ligands with a Cu-Cu distance of 3.042(4) Å. Each Cu(II) ion is in a distorted square-planar O2NBr environment. The compounds [Cu(N-oed)X]2 are diamagnetic and EPR-silent.
    Recueil des Travaux Chimiques des Pays-Bas. 09/2010; 112(5):309 - 313.
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    ABSTRACT: Twenty-six new coordination compounds are reported with methyl formate, ethyl acetate and diethyl malonate as the ligands, viz. [M(HCOOCH3)62+] [FeCl4−]2, [M(HCOOCH3)62+] [InCl4−]2, [M(CH3COOC2H5)62+] [SbCl6−]2, and [M(CH2(COOC2H5)2)32+] [SbCl6−]2, where M is Mg(II), Mn(II), Fe(II), Co(II), Ni(II), and Zn(II), and for the ethyl acetate and diethyl malonate solvates M is also Ca(II).In the complexes the carbonyl stretching vibration is shifted to lower frequencies with regard to this vibration in the free ligands. The magnitudes of these shifts are dependent on the metal ions. Frequency-shifts of other ligand vibrations are also observed. When the shifts are dependent on the metal ions, the magnitudes of the shifts follow the Irving-Williams sequence.For the methyl formate and ethyl acetate solvates a metal-dependent absorption band appears in the far infrared, which is attributed to the metal-ligand stretching vibration. This band could not be located for the diethyl malonate solvates.Investigation of ligand field spectra indicates the presence of octahedral species M(O)62+ in the solid compounds. Values for Dq and B for the Co(II) and Ni(II) compounds are reported, and the ligands are placed in the spectro-chemical and nephelauxetic series.
    Recueil des Travaux Chimiques des Pays-Bas. 09/2010; 89(4):353 - 367.
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    ABSTRACT: The synthesis and characterization of transition-metal coordination compounds with the novel, tetradentate ligand 1,6-bis(5-methyl-4-imidazolyl)-2,5-dithiahexane (abbreviated bidhx) are described. The nitrates have the general formula M(bidhx)(NO3)2·nH2O (M = Co, Ni, Cu, Zn; n = 0 - 2). With the isothiocyanate anion, monomers M(bidhx)(NCS)2 containing Co, Ni and Zn and Cu(bidhx)(NCS)(NO3) as well as a dimer Cu2(bidhx)(NCS)3 were isolated. In all compounds, bidhx acts as a tetradentate ligand with both thioether sulfurs and both imidazole nitrogens coordinating. All compounds are six-coordinated in a distorted octahedral geometry, although, for the copper mixed-anion compound, a five-coordination in a square pyramidal geometry may also be possible. A single crystal of [Ni(NCS)2(bidhx)](MeOH) was used in a structure determination: monoclinic, space group C2/c, a = 13.0516(7) Å, b = 16.383(1) Å, c = 10.3758(9), Å, β = 101.095(6) deg, Z = 4 and T = 293 K. The structure was solved using heavy-atom techniques and refined by least-squares methods to an R value of 0.0508. The nickel ion is in a distorted octahedral environment with the two thiocyanates in a cis position. The nickel to nitrogen distances are ca. 2.04 Å; the nickel to sulfur distances are ca. 2.5 Å.
    Recueil des Travaux Chimiques des Pays-Bas. 09/2010; 107(3):163 - 166.
  • W. L. Driessen, W. L. Groeneveld
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    ABSTRACT: A series of new complexes is reported with phosphorus oxychloride as a ligand: viz., complexes of Mg(II), Ca(II), Sr(II), Mn(II), Co(II), Ni(II), Cu(II) and Zn(II). Reflection spectra in the visible and near infrared region indicate an octahedral configuration of the metal ion and the POCl3 molecules.
    Recueil des Travaux Chimiques des Pays-Bas. 09/2010; 87(7):786 - 794.
  • H.J. Hoorn, P. de Joode, W.L. Driessen, J. Reedijk
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    ABSTRACT: Four potentially tridentate bis(2-pyridylalkyl)amines, differing in the number of methylene groups in the alkyl chain, have been coupled to the epoxy-containing bifunctional spacer (3-glycidoxypropyl)trimethoxysilane (GLYMO) and subsequently grafted onto silica. These ion exchangers were characterized by solid-state CP-MAS 13C-NMR and elemental analyses. The obtained ligand concentrations varied from 0.29-0.63 mmol/g ion exchanger. With the only exception of Alfa-GLYMO-bis(2-pyridyl)amine, which showed a very low capacity for any of the metal ions tested, these ion-exchange materials selectively absorbed Cu2+, with a maximum capacity of 0.22-0.59 mmol/g ion exchanger at pH 5.6, from aqueous solutions containing a mixture of the divalent metal ions Cu2+, Ni2+, Co2+, Cd2+ and Zn2+. The metal-uptake capacities and distribution coefficients established at different pH, correlate with the length of the alkyl bridge in the chelating ligand. The longer the alkyl spacer the lower the capacity and the metal-ligand complex stability at lower pH. The use of strong chelating tridentate N-donor ligands greatly increases the ligand occupation by metal ions. The Cu2+ uptake varies strongly with pH in the case of Alfa-GLYMO-bis[2-(2-pyridyl) ethyl]amine.
    Recueil des Travaux Chimiques des Pays-Bas. 09/2010; 115(3):191 - 197.
  • J. Reedijk, W. L. Driessen, W. L. Groeneveld
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    ABSTRACT: Methods of calculation for the parameters Dq and B from the ligand-field spectra of octahedral cobalt(II) compounds are discussed. A method of calculation is introduced, which considers the lowering of the 4T1g (F) state by spin-orbit splitting. This calculation is applied to the spectra of 43 octahedrally coordinated cobalt(II) compounds.With the aid of the spectral data an energy-level diagram is constructed, into which the absorption bands are fitted.Comparison of calculated Dq and B values with corresponding values for isomorphous nickel(II) compounds shows that - in general - the crystalfield parameter Dq is highest for cobalt, although the differences with nickel are less than 4 % in most cases. The calculated B values corresponds with those of Ni, with differences less than 1 % for many ligands.
    Recueil des Travaux Chimiques des Pays-Bas. 09/2010; 88(9):1095 - 1109.
  • W. L. Driessen, W. L. Groeneveld
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    ABSTRACT: A series of new complexes is reported with nitromethane as a ligand: viz. [M(CH3NO2)6]2+[SbCl6]2− where M is Mg(II), Ca(II), Sr(II), Mn(II), Fe(II), Co(II), Ni(II), and Zn(II).The compounds have been identified by chemical analysis and with the aid of physical measurements.No shift in the N → O stretching frequencies has been observed. The NO2 rocking mode (B1) shifts to higher frequencies.Ligand field spectra for the Co(II) and Ni(II) compounds are investigated. Values for Dq and B are reported and the ligand is placed in the spectrochemical and nephelauxetic series.It is concluded that complexes of nitromethane can serve as precursors of coordination compounds of other weakly nucleophilic ligands.
    Recueil des Travaux Chimiques des Pays-Bas. 09/2010; 88(4):491 - 498.
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    ABSTRACT: The novel didentate ligand 2-(3,5-dimethyl-1-pyrazolyl)ethylamine (Naed) and the tridentate ligand bis[2-(3,5-dimethyl-1-pyrazolyl)ethyl] amine (ddaH) were immobilized onto silica by two different methods. The first method involves the coupling of the ligand to silica, previously modified with (3-glycidyloxypropyl)trimethoxysilane (GLYMO). The second method involves the coupling of the ligand to the oxirane ring of GLYMO in a homogeneous reaction, followed by grafting onto silica, yielding the highest ligand concentrations on the silica (about 0.3 mmol/g silica). With the first method, only part of the epoxy group reacts with the ligand. With Naed, tertiary amines are also formed through reaction of the primary amine group of the ligand with two epoxy groups.These new ion-exchange materials selectively adsorb Cu2+ (maximum capacity 0.11–0.26 mmol Cu2+ per gram of ion exchange) at pH > 2 from aqueous solutions containing a mixture of the bivalent metal ions, Cu2+, Cd2+, Zn2+, Ni2+ and Co2+. For products containing the didentate ligand Naed as the chelating group, the metal-ion capacity decreases rapidly with decreasing pH, while the Cu2+ -uptake capacity for the product containing the tridentate ligand ddaH is comparatively high at low pH.
    Recueil des Travaux Chimiques des Pays-Bas. 09/2010; 111(9):371 - 378.
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    ABSTRACT: The synthesis and characterization of the copper tetrafluoroborate compound containing the bidentate N,S ligand 5-methyl-4-(ethylthiomethyl)imidazole (memi), [Cu(memi)2(BF4)2], is described. The activities of this compound and of [Cu(memi)2(H2O)2](NO3)2 as oxidation catalysts have been determined in the reaction of 2,6-dimethylphenol with molecular dioxygen to give polyphenylene oxide (PPO) and diphenoquinone (DPQ). For optimum catalysis, an additional base is required in order to dehydronate the phenol. Triethylamine proved to be most useful as a base. Initial reaction rates encountered are between 1 × 10−5 and 6 × 10−5M O2/s and ca. 50% of the phenol was converted after a reaction time of one hour. Less than 10% phenol was converted into DPQ. Both compounds have comparable reactivities.A single crystal of [Cu(memi)2(BF4)2] was used in an X-ray structure determination: monoclinic space group C2/c, a = 13.844(4) Å, b = 11.251(1) Å, c = 15.753(4) Å, β = 111.39 (2)°, Z = 4 and T = 293 K. The structure was solved using heavy-atom techniques and refined by least-squares methods to a residual R value of 0.050. The copper ion is in a centrosymmetric distorted octahedral environment with all chemically identical donor atoms in trans positions. The tetrafluoroborate anions are coordinated to the copper ion with relatively short distances, i.e. 2.55 Å; Cu-N and Cu-S distances are 1.93 and 2.41 Å.
    Recueil des Travaux Chimiques des Pays-Bas. 09/2010; 109(2):70 - 76.
  • Patrick Gamez, Peter G. Aubel, Willem L. Driessen, Jan Reedijk
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    ABSTRACT: The controlled oxidation of C–H bonds is one of the most challenging and difficult reactions in organic chemistry. Generally, it requires either stoichiometric amounts of toxic heavy metal salts or very expensive catalysts containing transition metals such as palladium, rhodium or ruthenium. The scientific community used to focus their investigations towards these relatively rare and costly elements while neglecting to look at how Nature performs these types of reactions. Biological systems only employ abundantly available metals like iron, zinc and copper. This review summarizes the background and the state of the art of enzymatic and biomimetic oxidation catalysts involving copper as the active metal center. Recent developments have shown the first very promising results in this incipient field.
    ChemInform 01/2010; 33(13).
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    ABSTRACT: A series of azathia- and azaoxathiacrown ether macrocycles have been prepared in good yields via the use of N-boc-bis(2-chloroethyl)amine as a precursor, which minimises undesirable side reactions and facilitates subsequent deprotection to the free cyclic amine. The mono-aza macrocycles, [12]aneNS3, [12]aneNOS2, [15]aneNS4, [15]aneNO2S2 and [16]aneNS4 have been prepared via this route. The single-crystal X-ray structure of [12]aneNS3·HBr·2H2O confirms the macrocycle to be distorted quadrangular with the S-centres lying along the edges and six out of 12 torsion angles less than 90°. The synthesis of di-aza macrocycles utilising the diamide precursors, N,N′-bis(chloroacetyl)-1,2-diaminoethane and N,N′-bis(chloroacetyl)-1,3-diaminopropane, affords the free macrocycles [12]aneN2S2, [15]aneN2S3, [15]aneN2OS2, [16]aneN2S3 and [19]aneN2S4 after reduction of the intermediate cyclic amides. Reaction of 3,6-dioxa-1,8-octanediamine with the dimethyl ester of thiadiglycolic acid followed by reduction affords [15]aneN2O2S, while the hydroxy-substituted macrocycles [20]aneS6(OH)2, [13]aneS4(OH), and [26]aneS8(OH)2 have been prepared by reaction of 1,3-dichloro-2-hydroxypropane with the appropriate dithiol. The crystal structure of [20]aneS6(OH)2 shows two endo- and four exo-dentate S-centres as observed in the parent [18]aneS6. The N-aryl substituted macrocycles N-4-NO2Ph-[12]aneNS3 (N-4-nitrophenyl-7-aza-1,4,10-trithiacyclododecane) and N-4-NH2COPh-[12]aneNS3 (N-4-benzamido-7-aza-1,4,10-trithiacyclododecane) have been prepared by reaction of 4-substituted bis-tosylated N,N-bis(2-hydroxyethyl)aniline with 3-thia-1,5-pentanedithiol.
    Polyhedron 01/2006; 25(2):599-612. · 1.81 Impact Factor
  • Jurjen Kramer, Willem L. Driessen, Klaus R. Koch, Jan Reedijk
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    ABSTRACT: The recovery of Pd, Pt, and Rh from batches of authentic industrial precious metal refinery (PMR) effluents containing large amounts of Ni, Cu, and Fe ions and relatively small amounts of the expensive Pt, Pd, and Rh ions was investigated with silica‐based anion exchangers containing monoamine, ethylenediamine, and diethylenetriamine functionalities. All platinum group metal (PGM) recoveries have proven to be highly selective over various base metal ions, such as Cu. Quantitative recovery of Pd and Pt from some of the PMR effluents was effected by these ion exchangers, whereby HCl appears to be a powerful desorbent. Moreover, in most cases, Pd and Pt have been completely stripped from the ion exchangers with thiourea or with a combination of thiourea and HCl. Rh recovery from a base metal refinery (BMR) effluent was found to be less efficient, with maximum adsorption values of just over 20% and with a maximum desorption of about 50%. Rh stripping after extraction from one of the PMR effluents appeared to be much more successful. The well‐known difficulties in Rh recovery can be largely attributed to the occurrence of several kinetically inert species in hydrometallurgical effluents.
    Separation Science and Technology - SEPAR SCI TECHNOL. 01/2005; 39(1):63-75.
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    ABSTRACT: The Mannich condensation of formaldehyde with some amines and imidazoles rendered three bis-(amine–imidazole) ligands in a simple one pot reaction. Although these ligands are formally dinucleating, the copper(II) ions are held far apart, as shown by the Xray structures of five copper(II) compounds obtained with these ligands. Consequentially, these copper(II) compounds behave magnetically mononuclear.
    Inorganica Chimica Acta - INORG CHIM ACTA. 01/2005; 358(7):2167-2173.
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    ABSTRACT: A new pyrazole-based ligand, namely 1,3-bis(3,5-dimethylpyrazol-1-yl)-2-butanoic acid (Hbdmpb) was synthesised together with its copper complex Na[Cu(bdmpb)2(OOCCH3)H2O]·4H2O. Both the free ligand and its Cu compound were fully characterised and their crystal structures were determined by X-ray analysis. The free-ligand molecular structure is uneventful. The Cu compound is highly unusual, as the pyrazole nitrogen atoms do not bind to the Cu ion. The copper(II) ion is coordinated by four nearly coplanar oxygen atoms from two dehydronated ligands bdmpb (CuO(1a) 1.942(4), CuO(1b) 1.933(4) Å), a monodentate acetate group (CuO(1) 1.927(3) Å) and a water molecule (CuO(1w) 1.937(4) Å). The nitrogen atoms of the pyrazole rings do not coordinate to the metal center, but instead are involved in strong intramolecular hydrogen bonds. The coordinated water molecule is strongly H-bonded to two pyrazole N atoms from two bdmpb ligands (N(12a)⋯HO(1w) 2.762(7), N(12b)⋯HO(1w) 2.774(7) Å). The other two pyrazole N atoms with a lone pair are hydrogen-bonded to water molecules in the lattice (N(22a)⋯HO(2w) 2.763(7), N(22b)⋯HO(6w) 2.892(7) Å). The sodium ion is six-coordinated by the oxygen atom O(2) of the acetato ligand and by five water molecules. The EPR spectrum recorded in the solid state shows a characteristic signal for an axial anisotropic S=1/2 species. The spectrum recorded in methanol glass confirms the absence of the coordination of pyrazole nitrogen atoms to the copper centers.
    Inorganica Chimica Acta - INORG CHIM ACTA. 01/2005; 358(4):1135-1140.
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    ABSTRACT: In this study an unusual dinuclear bis-chloride bridged Mn(II) compound, [Mn(l-Cl)(biz) 2 ] 2 Cl 2 (in which biz = 2,2 0 -bi-imidazo-line), has been described and characterised. Also the magnetic susceptibility and EPR investigations are made. The distorted octa-hedral geometry around the Mn(II) ion is formed by four nitrogen atoms of two dichelating biz ligands and two bridging chloride atoms. The lattice is further stabilised by hydrogen bonds between uncoordinating N atoms of the ligand and the coordinating and uncoordinating chloride atoms. Magnetic susceptibility measurements reveal a weak ferromagnetic interaction between the two high-spin Mn(II) ions of J = 0.33 cm À1 .
    Polyhedron 10/2004; 23(15). · 1.81 Impact Factor
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    ABSTRACT: The synthesis and crystal structures of four CdII macrocyclic complexes containing mixed N-, O- and S-donors, [Cd(NO3)2([12]aneN2S2)] (1), [Cd(NO3)2([12]aneNS3)] (2), [Cd(NO3)2([15]aneNO2S2)] (3) and [Cd(NO3)([15]aneN2O2S)]NO3 (4), are presented. The metal ion is coordinated outside of the macrocyclic cavity in the complexes of the smaller macrocycles ([12]aneN2S2 and [12]aneNS3) while the flexibility of the larger macrocycles in and allows very different conformations to be adopted with a 'butterfly' geometry in and a flattened geometry in. No correlation between the number of sulfur donors and Cd-S bond distance in these types of complexes is observed, although the number and binding mode of the nitrato ligands is determined by the conformation and binding mode of the macrocycle. The position of the nitrato ligand also influences, through steric conflicts with the macrocyclic donor atoms, the bond distances in both ligand systems.
    Dalton Transactions 08/2004; · 3.81 Impact Factor
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    ABSTRACT: The syntheses, spectroscopic properties and crystal structures of two new base adducts of bis(2,4-pentanedionato)cobalt(II) with 3,5-dimethylpyrazole (Hdmpz) (1) and dimethylethanolamine (Hdmea) (2) are described. The crystal structures of both compounds contain monomeric CoII complexes with cis-distorted octahedral environments, even for the monodentate Hdmpz ligand which is quite unique. These mononuclear complexes are linked by hydrogen bonds between the anionic 2,4-pentanedionato groups and the neutral Hdmpz or Hdmea ligands. The low-temperature polycrystalline-powder EPR spectra display unresolved metal hyperfine coupling. The g values are anisotropic in both cases; the anisotropy is larger for the Hdmea adduct. Interesting insights into the coordination effects were gained with the help of electron-density descriptors (Laplacian of density and Natural Bond Orbitals). This revealed a slight deviation of the coordinating lone pairs of the pentanedionato ligands from the Co−O axis, as well as a nonstandard hybrid composition. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
    Berichte der deutschen chemischen Gesellschaft 04/2004; 2004(9):1963 - 1969. · 2.94 Impact Factor

Publication Stats

389 Citations
256.35 Total Impact Points

Institutions

  • 1985–2010
    • Leiden University
      • Section of Molecular Physics
      Leyden, South Holland, Netherlands
  • 2004
    • Université de Reims Champagne-Ardenne
      • Institut de Chimie Moléculaire de Reims (ICMR)
      Rheims, Champagne-Ardenne, France
  • 2002
    • Stellenbosch University
      Stellenbosch, Western Cape, South Africa
  • 1997
    • University of Catania
      Catania, Sicily, Italy
  • 1990–1997
    • University of Strathclyde
      • Department of Pure and Applied Chemistry
      Glasgow, Scotland, United Kingdom
  • 1985–1996
    • Universiteit Utrecht
      • • Bijvoet Institute for Biomolecular Research
      • • Department of Chemistry
      Utrecht, Provincie Utrecht, Netherlands
  • 1991
    • University of Massachusetts Amherst
      • Department of Chemistry
      Amherst Center, MA, United States