Allan H. White

University of Western Australia, Perth City, Western Australia, Australia

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Publications (807)1657.41 Total impact

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    ABSTRACT: [RuCl(arene)(μ-Cl)]2 dimers were treated in a 1:2 molar ratio with sodium or thallium salts of bis- and tris(pyrazolyl)borate ligands [Na(Bp Br 3)], [Tl(Tp Br 3)], and [Tl(Tp(iPr, 4Br) )]. Mononuclear neutral complexes [RuCl(arene)(κ(2) -Bp Br 3)] (1: arene=p-cymene (cym); 2: arene=hexamethylbenzene (hmb); 3: arene=benzene (bz)), [RuCl(arene)(κ(2) -Tp Br 3)] (4: arene=cym; 6: arene=bz), and [RuCl(arene)(κ(2) -Tp(iPr, 4Br) )] (7: arene=cym, 8: arene=hmb, 9: arene=bz) have been always obtained with the exception of the ionic [Ru2 (hmb)2 (μ-Cl)3 ][Tp Br 3] (5'), which formed independently of the ratio of reactants and reaction conditions employed. The ionic [Ru(CH3 OH)(cym)(κ(2) -Bp Br 3)][X] (10: X=PF6 , 12: X=O3 SCF3 ) and the neutral [Ru(O2 CCF3 )(cym)(κ(2) -Bp Br 3)] (11) have been obtained by a metathesis reaction with corresponding silver salts. All complexes 1-12 have been characterized by analytical and spectroscopic data (IR, ESI-MS, (1) H and (13) C NMR spectroscopy). The structures of the thallium and calcium derivatives of ligand Tp Br 3, [Tl(Tp Br 3)] and [Ca(dmso)6 ][Tp Br 3]2 ⋅2 DMSO, of the complexes 1, 4, 5', 6, 11, and of the decomposition product [RuCl(cym)(Hpz(iPr, 4Br) )2 ][Cl] (7') have been confirmed by using single-crystal X-ray diffraction. Electrochemical studies showed that 1-9 and 11 undergo a single-electron Ru(II) →Ru(III) oxidation at a potential, measured by cyclic voltammetry, which allows comparison of the electron-donor characters of the bis- and tris(pyrazol-1-yl)borate and arene ligands, and to estimate, for the first time, the values of the Lever EL ligand parameter for Bp Br 3, Tp Br 3, and Tp(iPr, 4Br) . Theoretical calculations at the DFT level indicated that both oxidation and reduction of the Ru complexes under study are mostly metal-centered with some involvement of the chloride ligand in the former case, and also demonstrated that the experimental isolation of the μ(3) -binuclear complex 5' (instead of the mononuclear 5) is accounted for by the low thermodynamic stability of the latter species due to steric reasons.
    Chemistry 02/2014; 20(13):3689. · 5.93 Impact Factor
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    ABSTRACT: Six scorpionate complexes of group 10–12 metal elements (CuI, CuII, ZnII, and CdII) containing the anionic hydrotris[3-(2′-thienyl)pyrazol-1-yl]borate (TpTn) ligand were prepared from the reaction of the thallium(I) salt of TpTn with the corresponding metal acceptors in chloroform solution. The air- and heat-stable complexes were characterized by analytical and spectroscopic methods (IR, conductivity, ESI-MS, 1H NMR and 13C NMR solution data) and structurally characterized by single-crystal X-ray studies. The ZnII complexes [Zn(TpTn)X] (X = Cl or Br) contain a tripodal tridentate TpTn ligand, in which the tetrahedral metal environment is completed by a halide; in [Cd(TpTn)2], cadmium is found in an octahedral environment coordinated by two TpTn ligands. In [Cu(TpTn)(PPh3)]·CHCl3 and [Cu(TpTn)(OC(O)CH3)], TpTn is also coordinated in the tripodal fashion, in which the copper environment is completed by a triphenylphosphine ligand in the former complex and by a symmetrically coordinated bidentate acetate ligand occupying trans-coordinated sites in the latter complex. The reaction of [Zn(TpTn)X] with an excess amount of [Tl(TpTn)] in MeOH yielded [Zn(TpTn)2] and TlX, whereas the reaction of [Zn(TpTn)X] with Na(Tp) gave [Zn(TpTn)2] and [Zn(Tp)2] in a 1:1 molar ratio but not [Zn(TpTn)(Tp)]. By contrast, the reaction of [Tl(TpTn)] with copper(II) sulfate monohydrate in chloroform gave a green powder, which was identified as the [(Hpz3Tn)4CuSO4](∞|∞) coordination polymer containing OSO2O bridging sulfate groups and four coordinated pyrazole ligands on each metal center, the latter of which arises from the decomposition of the TpTn ligand through B–N bond breaking. Similarly, the interaction between [Tl(TpTn)] and platinum(II) diiodide in chloroform/DMSO proceeded through TpTn decomposition to afford a monomeric trans-[(Hpz3Tn)2PtI2]·2(CH3)2SO complex, wherein two neutral pyrazole ligands are coordinated to the PtII center.
    Berichte der deutschen chemischen Gesellschaft 01/2014; 2014(3):546-554. · 2.94 Impact Factor
  • Zeitschrift für anorganische Chemie 10/2013; 639(12‐13). · 1.16 Impact Factor
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    ABSTRACT: Adducts of a number of tertiary pnicogen ligands ER3 (triphenyl-phosphine and -arsine (PPh3,AsPh3), diphenyl,2-pyridylphosphine (PPh2py), tris(4-fluorophenyl)phosphine (P(C6H4-4F)3), tris(2-tolyl)phosphine (P(o-tol)3), tris(cyclohexyl)phosphine (PCy3)), with silver(I) thiocyanate, AgSCN are structurally and spectroscopically characterized. The 1:3 AgSCN:ER3 complexes structurally defined (for PPh3,AsPh3 (diversely solvated)) take the form [(R3E)3AgX], the thiocyanate X = NCS being N-bound, thus [(Ph3E)Ag(NCS)]. A 1:2 complex with PPh2py, takes the binuclear form [(pyPh2P)2Ag(SCNNCS)Ag(PPh2py)2] with an eight-membered cyclic core. 1:1 complexes are defined with PPh2py, P(o-tol)3 and PCy3; binuclear forms [(R3P)Ag(SCNNCS)Ag(PR3)] are obtained with P(o-tol)3 (two polymorphs), while novel isomeric tetranuclear forms, which may be envisaged as dimers of dimers, are obtained with PPh2py, and, as further polymorphs, with PCy3; these latter may be considered as extensions of the ‘cubane’ and ‘step’ forms previously described for [(R3E)AgX]4 (X = halide) complexes. Solvent-assisted mechanochemical or solvent-assisted solid-state synthesis methods were employed in some cases, where complexes could not be obtained by conventional solution methods, or where such methods yielded a mixture of polymorphs unsuitable for solid-state spectroscopy. The wavenumbers of the ν(CN) bands in the IR spectra are in broad agreement with the empirical rule that distinguishes bridging from terminal bonding, but exceptions occur for compounds that have a double SCN bridged dimeric structure, and replacement of PPh3 with PPh2py apparently causes a significant decrease in ν(CN) to well below the range expected for bridging SCN in these structures. 31P CP MAS NMR spectra yield additional parameters that allow a correlation between the structures and spectra.
    Dalton Transactions 11/2012; 42(1):277-291. · 3.81 Impact Factor
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    ABSTRACT: A number of adducts of copper(I) thiocyanate with bulky tertiary phosphine ligands, and some nitrogen-base solvates, were synthesized and structurally and spectroscopically characterised. CuSCN:PCy3 (1:2), as crystallized from pyridine, is shown by a single crystal X-ray study to be a one-dimensional polymer ...(Cy3P)2CuSCN(Cy3P)2CuSCN... (1) with the four-coordinate copper atoms linked end-on by S-SCN-N bridging thiocyanate groups. A second form (2), obtained from acetonitrile, was also identified and shown by IR and 31P CPMAS NMR spectroscopy to be mononuclear, with the magnitude of the dν(Cu) parameter measured from the 31P CPMAS and the ν(CN) value from the IR clearly establishing this compound as three-coordinate [(Cy3P)2CuNCS]. Two further CuSCN/PCy3 compounds CuSCN:PCy3 (1:1) (3), and CuSCN:PCy3:py (1:1:1) (4) were also characterized spectroscopically, with the dν(Cu) parameters indicating three- and four-coordinate copper sites, respectively. Attempts to obtain a 1:2 adduct with tri-t-butylphosphine have yielded, from pyridine, the 1:1 adduct as a dimer [(Bu(t)3P)((SCN)(NCS))Cu(PBu(t)3)] (5), while similar attempts with tri-o-tolylphosphine (from acetonitrile and pyridine (= L)) resulted in solvated 1:1:1 CuSCN:P(o-tol)3:L forms as dimeric [{(o-tol)3P}LCu((SCN)(NCS))CuL{P(o-tol)3}] (6 and 8). The solvent-free 1:1 CuSCN:P(o-tol)3 adduct (7), obtained by desolvation of 6, was characterized spectroscopically and dν(Cu) measurements from the 31P CPMAS NMR data are consistent with the decrease in coordination number of the copper atom from four (for 6) (P,N(MeCN)Cu,S,N) to three (for 7) (PCuS,N) upon loss of the acetonitrile of solvation. These results are compared with those previously reported for mononuclear and binuclear PPh3 adducts which demonstrate a clear tendency for the copper centre to remain four-coordinate. The IR spectroscopic measurements on these compounds show that bands in the far-IR spectra provide a much more definitive criterion for distinguishing between bridging and terminal bonding than does an often-used empirical rule based on ν(CN) in the mid-IR, which leads to the wrong conclusion in some cases.
    Dalton Transactions 05/2012; 41(25):7513-25. · 3.81 Impact Factor
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    ABSTRACT: The complex Ru{C≡CC(CN)═C(CN)2}(dppe)Cp* (1), containing the new tricyanovinylethynyl (3,4,4-tricyanobut-3-en-1-ynyl) ligand, undergoes ready substitution of the 3-cyano group by nucleophiles (Nu) such as H, Me, Pri, Bu, But, mesityl, OMe, OBut, OCH2CH═CH2, NHEt, NEt2, and PPh2 to give Ru{C≡CC(Nu)═C(CN)2}(dppe)Cp*. The X-ray diffraction structures of several of the resulting complexes are reported and, for the mesityl and PPh2 products, show that isomerization to the 3,5-dimethylbenzyl and oxidation to the phosphine oxide have respectively occurred.
    Organometallics 05/2012; 31(11):4174–4181. · 4.15 Impact Factor
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    ABSTRACT: The complex [(Ph(3)P)(2)Ag(H(2)cit)]·EtOH (1; H(2)cit(-) = dihydrogencitrate = C(6)H(7)O(7)(-)) contains [(Ph(3)P)(2)Ag(H(2)cit)] molecules in which the silver atom is coordinated to two PPh(3) molecules and the two oxygen atoms of one of the 'terminal'/1-carboxylate groups of the dihydrogencitrate group. The molecules form centrosymmetric hydrogen-bonded dimers in the solid. In [{(Ph(3)P)(2)Ag}(2)(Hcit)], (2), unsymmetrical deprotonation of the citrate grouping is found, from the 1- and 3- (i.e. terminal and central) carboxylates: [(Ph(3)P)(2)Ag(O(2)CCH(2)C(OH) (CH(2)COOH)CO(2))Ag(PPh(3))(2)]. The above complexes, as well as [(Ph(3)P)(3)Ag(H(2)cit)] (3) were prepared via conventional solution methods, involving the reaction of trisilver(I) citrate, citric acid and triphenylphosphine, and by a mechanochemical method involving the reaction of silver(I) oxide, citric acid and triphenylphosphine. IR studies of 1-3 show the presence of coordinated carboxylate and free carboxylic acid groups in the mono- and di-hydrogencitrate ligands, and the formation of 2 from 1 shows that dihydrogencitrate deprotonation can occur upon dissolution of 1 in protic solvents. High-field (9.40 T) (31)P CPMAS NMR spectra were recorded and analysed, yielding heteronuclear (1)J((107/109)Ag,(31)P) and homonuclear (2)J((31)P,(31)P) spin-spin coupling constants.
    Dalton Transactions 03/2012; 41(17):5409-17. · 3.81 Impact Factor
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    ABSTRACT: The crystal structures of an array of 2-R,4-oxo-[1,3-b]-naphthodioxanes (R = H, Me, Et, i-Pr, n-Bu, CCl3, i-propylideneglyceral) have been determined at 100 K, together with a more limited series of the isomeric 2-R,4-oxo-[1,3-a]-naphthodioxanes (R = Et, i-Pr, n-Bu, i-propylideneglyceral), permitting a study of the effects of substituent and ring fusion variation on the crystal packing of neutral molecules that are otherwise essentially planar. We have conducted an analysis of Hirshfeld surfaces (a definition of an outer contact surface of a molecule within a crystal) for all eleven compounds and follow the changes of different properties on these surfaces upon systematic variation of the substituent R. Not only qualitative information by means of fingerprint plots, but also quantitative information by means of melting point correlations are presented. The results show the extent to which C–HO hydrogen bonds and C–Hπ/ππ interactions contribute positively to the lattice energies on the one hand, and HH contacts negatively on the other. The percentage of HH contacts as closest contacts on the Hirshfeld surfaces is a universally applicable measure of the crystal lattice energy and can be used as a reference for the importance of other types of contacts.
    CrystEngComm 01/2012; 14(3):1083-1093. · 3.88 Impact Factor
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    ABSTRACT: The interaction between hexabromoethane and [CpRu(CO)(2)Br] (Cp = (eta-C5H5), results in the deposition of two different isostoichiometric co-crystals, 2[CpRu(CO)(2)Br]center dot C2Br6, one crystallising in space group P (1) over bar (Z = 1) and the other in P2(1)/n (Z = 4). These were produced in the reaction of HCBr3 and [(CpRu(CO)(2))(2)] under indoor illumination, following a slight modification of the literature procedure. The origin of the hexabromoethane is as yet unknown but it appears to have been formed in the reaction rather than being an impurity in the bromoform. We have analysed the structures using the Hirshfeld surface approach and electrostatic potentials, supported by DFT theoretical calculations to better define the nature of intermolecular interactions in the solid state. The results indicate that the most significant interactions within both crystal forms arise not from the closest van der Waals contacts but, rather, from more distant interactions between the unsymmetrical electron distributions about the bromine atoms in the solvate and substrate molecules.
    CrystEngComm 01/2012; 14(3):804-811. · 3.88 Impact Factor
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    ABSTRACT: Single crystal X-ray studies are presented for the `piano-stool' structures [CpRu,Os(CO)(2)Cl], [Cp'Ru(CO)(2)X] (X = Cl, Br, I (redetermination)), [Cp*Ru(CO)(2)Cl] (two phases), enabling the assembly of comparative geometric data for the [CpM(CO)(2)Cl] (M = Fe, Ru, Os), [Cp, Cp'Ru(CO)(2)X] (X = Cl, Br, I) and [(CpRu)-Ru-x(CO)(2)Cl] (Cp-x = Cp (eta-C5H5), Cp' (eta-C5H4CH3), Cp* (eta-C5CH3)(5), Cp-Ph (eta-C-5(C6H5)(5))). In the [Cp'Ru(CO)(2)X] arrays, the methyl groups are found to consistently lie `eclipsed' visa-vis the halogen substituents, with a concomitant tilt of the Cp ring; the reasons for this are explored theoretically.
    CrystEngComm 01/2012; 14(3):812-818. · 3.88 Impact Factor
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    ABSTRACT: Syntheses of a number of adducts of silver(I) (bi-)carbonate with triphenylphosphine, both mechanochemically, and from solution, are described, together with their infra-red spectra, (31)P CP MAS NMR and crystal structures. Ag(HCO(3)):PPh(3) (1:4) has been isolated in the ionic form [Ag(PPh(3))(4)](HCO(3))·2EtOH·3H(2)O. Ag(2)CO(3):PPh(3) (1:4) forms a binuclear neutral molecule [(Ph(3)P)(2)Ag(O,μ-O'·CO)Ag(PPh(3))(2)](·2H(2)O), while Ag(HCO(3)):PPh(3) (1:2) has been isolated in both mononuclear and binuclear forms: [(Ph(3)P)(2)Ag(O(2)COH)] and [(Ph(3)P)(2)Ag(μ-O·CO·OH)(2)Ag(PPh(3))(2)] (both unsolvated). A more convenient method for the preparation of the previously reported copper(I) complex [(Ph(3)P)(2)Cu(HCO(3))] is also reported.
    Dalton Transactions 06/2011; 40(27):7210-8. · 3.81 Impact Factor
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    ABSTRACT: Methyl(phenoxo)mercury(II) may be obtained from the reaction of methyl(chloro)mercury(II) with silver(I) oxide, followed by addition of phenol. The dominant motif of the structure is a pair of independent MeHgOPh aggregates (Hg—C,O 2.05(2) Å, 2.06(1) Å (x2); C-Hg-O 176.6(5)°, 176.3(5)°) loosely associated about a quasi-inversion centre by Hg···O interactions (2.702(9) Å, 2.719(9) Å) to form a dimer (Hg-O-Hg′ 106.0(4)°, 106.5(4)°; O-Hg-O′ 73.0(3)°, 72.6(3)°), the dimer stacking up the short crystallographic c axis (= 6.914(1) Å) at spacings c/2. Vibrational spectroscopic studies are insensitive to the associative interactions. Key words: mercury, methylmercury, organomercury, structure, aryloxide, phenoxide.
    Canadian Journal of Chemistry 02/2011; 84(2):77-80. · 0.96 Impact Factor
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    ABSTRACT: Syntheses, single crystal X-ray structural and spectroscopic characterizations are described for a variety of adducts of silver salts with ethylenethiourea (etu). Ag2SO4/etu (1:6) is isomorphous with its previously studied copper(I) counterpart, the [Ag(S-etu)3]+ species disposed with their silver atoms on crystallographic 3-axes, one of the two independent cations being slightly perturbed by a distant O-sulfate approach along that axis. In AgCl/etu (1:3), the silver atom is in a four-coordinate ClAgS3 environment, while AgNO3/etu (1:3) takes the form [(etu)2Ag(µ-S-etu)2Ag(etu)2](NO3)2. AgBr/etu (1:2) is binuclear [(etu)2Ag(µ-Br)2Ag(etu)2)], unlike its previously studied copper counterpart, which is [(etu)BrCu(µ-S-etu)2CuBr(etu)]. AgCl/etu (4:6) is an interesting ionic polymer [ClAg4(etu)6](∞|∞)Cl3, containing a novel one-dimensional polymeric cation. Bands in the far IR spectra of these compounds are assigned to v(AgS) and v(AgX) (X = halogen) modes, and a correlation between v(AgS) and the Ag–S bond length d(AgS) is established for silver complexes involving the etu ligand.Key words: silver, sulfur ligands, X-ray crystal structure, coordination chemistry, complexes.
    Canadian Journal of Chemistry 02/2011; 87(1):161-170. · 0.96 Impact Factor
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    ABSTRACT: A representative series of polymeric hydrated lanthanoid perfluoroadipates [Ln2(pfad)3(H2O)n]·mH2O (Ln = La, Ce, Nd, Gd, Yb) has been prepared from the reaction of perfluoroadipic acid with either the appropriate lanthanoid oxide or Ce2(CO3)3 in water. X-ray crystal structures showed [Ln2(pfad)3(H2O)10]·4H2O (La, Nd) to be two-dimensional inorganic polymers, which contain nine-coordinate Ln atoms to which are attached five water molecules and four carboxylate oxygen atoms. Two pfad ligands bridge two Ln atoms through one carboxylate group, the other being free, whilst one pfad ligand bridges four Ln atoms in a µ4-(η1,η1/η1,η1) manner. In two-dimensional polymeric [Yb2(pfad)2(H2O)8](pfad)·6H2O, each eight-coordinate ytterbium atom has four water ligands and four carboxylate oxygen donor atoms. The two carboxylate ligands bind in a µ4-(η1,η1/η1,η1) manner, and there is one pfad counter-ion per two ytterbium atoms. These structures show features quite different from those of many lanthanoid adipate complexes [Ln2(ad)3(H2O)n]·mH2O, but there is no F-Ln coordination. From the reaction of [Nd2(pfad)3(H2O)10]·4H2O with benzene-1,2-disulfonic acid (H2bds), the mixed ligand complex [Nd2(bds)2(pfad)(H2O)8] was isolated. This is a one-dimensional polymer featuring Nd2(bds)2 units linked together by µ-η2,η2 pfad ligands. Each Nd atom is nine-coordinate with three sulfonate oxygen donors, two carboxylate oxygen atoms, and four water ligands, and the bds ligands bind in the new µ-η2(O,O′),η1(O′′) manner for Ln complexes. Surprisingly, [Na2pfad] was isolated unhydrated from water, the six-coordinate Na atoms being coordinated by four carboxylate oxygen atoms and two (C)-F atoms in an octahedral array. The ligands are duodecadentate, each –CF2CO2 unit binding to five different sodium ions through four oxygen and one α-F atom with the second α-F atom bound to a sodium ion in a OC(O)CF-Na chelate ring.Key words: rare earths, lanthanoid, X-ray crystal structures, adipates, carboxylates.
    Canadian Journal of Chemistry 02/2011; 87(1):121-133. · 0.96 Impact Factor
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    ABSTRACT: In the course of studies on hybrid antibacterials incorporating 2-aryl-5-nitro-1H-indole moieties as potential bacterial NorA efflux pump inhibitors, the compound 1-[2-(5-nitro-1H-indol-2-yl)phenyl]methylpyridinium chloride (2) was synthesized and structurally characterized. This pyridinium chloride salt crystallized in the monoclinic space group P2(1)/c with the following unit cell dimensions: a 10.274(3) Å, b 13.101(4) Å, c 13.439(4) Å, b 107.702(7)°, V 1723.2(9) ų, Z (f.u.) = 4; R1 = 0.048, and wR2 = 0.13. Of interest in the single crystal X-ray structure is the (intramolecular) disposition of the pyridinium plane over the indole heterocyclic residue [interplanar dihedral angle 17.91(4)°].
    Molecules 01/2011; 16(9):7627-33. · 2.43 Impact Factor
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    ABSTRACT: Nine new organotin complexes, namely [SnR2XY(BtzH)2] (1: R=Me, X=Y=Cl, 2: R=Me, X=Y=Br, 3: R=nBu, X=Cl, Y=OH; 4: R=Ph, X=Y=Cl; 5a: R=Me, X=Y=NO3; 5b: R=Me, X=Y=ClO4) and [SnR2X2(5-NO2indH)2] (6: R=Me, X=Cl; 7: R=nBu, X=Cl; 8: R=Me, X=5-NO2ind) were obtained by reaction of SnR2X2 with BtzH (1,2,3-benzotriazole) and 5-NO2indH (5-nitroindazole). These compounds were characterized by IR, NMR and ESI MS, and 1 is shown by a single crystal X-ray study to comprise mononuclear centrosymmetric molecules, all pairs of ligands being mutually opposed in a quasi-octahedral coordination sphere. Sn–Cl, C, N are 2.5700(5), 2.108(2), 2.357(2)Å. A new triclinic (P1¯) polymorph of the binuclear [{tBu2ClSn(μ-OH)}2], 9 is also described (cf. the earlier monoclinic (P21/c)). The unit cell contents comprise a pair of centrosymmetric dimers: Sn–O are 2.042(4)–2.215(4), Sn–Cl 2.489(2), 2.491(2), Sn–C 2.166(6)–2.203(7) Å, O–Sn–O 68.4(2) (x2), and Sn–O–Sn 111.6(2)° (x2).
    Inorganic Chemistry Communications - INORG CHEM COMMUN. 01/2011; 14(1):133-136.
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    ABSTRACT: New (Q)2SnR2 derivatives (HQ in general; in detail: HQCHPh2=4-diphenylacetyl-3-methyl-1-phenyl-5-pyrazolone; HQBn=3-methyl-1-phenyl-4-phenylacetyl-5-pyrazolone; HQnaph=3-methyl-4-naphthoyl-1-phenyl-5-pyrazolone; R=CH3, C2H5, C6H11, n- and t-C4H9, C6H5,) have been synthesised and characterised by analytical and spectral techniques. Variable temperature NMR studies of (QCHPh2)2SnR2 derivatives (R=CH3 and C2H5) in chlorohydrocarbon solvents indicate a fluxional behaviour, with rapid interconversion between six- and five-coordinate species, the latter containing a bidentate acylpyrazolonate and a monodentate one. The X-ray crystal structures of the diorganotin(IV) derivatives (QCHPh2)2SnMe2, (QCHPh2)2SnEt2, (QBn)2SnMe2 and (Qnaph)2SnBun2, inclusive of a representative of each Qx family, show the metal centres in a skewed trans octahedral configuration. The 4-acyl moiety of the β-diketonate donor exerts a steric effect which is correlated to structural behaviour in the solid and solution state. A solid state 119Sn CPMAS NMR study of the (QBn)2SnR2 (R=CH3, C2H5, t-C4H9 and C6H5) complexes shows a marked deshielding effect and upfield movement of the 119Sn isotropic chemical shift (δiso) through this series. The 119Sn chemical shift spans (Ω) are the largest reported for directly oxo-coordinated Sn(IV) systems, although the markedly reduced Ω value for the (QBn)2SnPh2 complex may be indicative of a cis octahedral coordination, in contrast to the trans octahedral coordination characterising the other complexes of this suite.
    Inorganica Chimica Acta - INORG CHIM ACTA. 01/2011; 367(1):73-84.
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    ABSTRACT: Mixed carboxylate complexes of cerium(III) and yttrium(III), [Ce2(OAc)4(salH)2(OH2)4]·4HOAc and [Y2(OAc)4(salH)2(OH2)4]·2H2sal (HOAc, H2sal ≡ acetic, salicylic acids) have been structurally characterized as tetrakis(acetic) and bis(salicylic) acid solvates, respectively. The dinuclear complex components take an identical form: [(OAc-O,O′)(H2O)2Ln(O,μ-O′-OAc)2(O-Hsal-O′)2Ln(OH2)2(O,O′-OAc)], with bridging pairs of acetate and salicylate ligands. The solvating acid molecules are closely and elegantly associated with the dinuclear complex via hydrogen bonding, these aggregates in turn being held together in the lattice by interactions between water molecule hydrogen atoms and neighboring carboxylate oxygen atoms.
    Zeitschrift für anorganische Chemie 11/2010; 636(13‐14). · 1.16 Impact Factor
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    ABSTRACT: Treatment of Co(3)(mu(3)-CC[triple bond]CR)(mu-dppm)(CO)(7) with O(2) (air) in the presence of [FcH]PF(6) afforded Co(3){mu(3)-CC(O)R}(mu-dppm)(CO)(7) by the formal conversion -C[triple bond]C- + O-O --> >C-O + C[triple bond]O. In this way, complexes with R = Ph, Fc, and W(CO)(3)Cp, bis-clusters {Co(3)(mu-dppm)(CO)(7)}(2){mu(3):mu(3)-[[triple bond]C(O)(C[triple bond]C)C[triple bond]]}, {Co(3)(mu-dppm)(CO)(7)}(2){mu(3):mu(3)-[[triple bond]C(O)(C[triple bond]C)(x)C(O)C[triple bond, length as m-dash]]} (x = 1, 2), and {Co(3)(mu-dppm)(CO)(7)}(2){mu(3):mu(3)-[[triple bond]CC(O)C[triple bond, length as m-dash]CC(6)H(4)C[triple bond]CC(O)C[triple bond]]}, and heterometallic bis-clusters {Co(3)(mu-dppm)(CO)(7)}{mu(3):mu(3)-[[triple bond]CC(O)C[triple bond]CC[triple bond]]}{M(3)(mu-H)(3)(CO)(9)} (M = Ru, Os) have been prepared. Single-crystal XRD structure determinations of several products are reported together with that of precursor {Co(3)(mu-dppm)(CO)(7)}(2){mu(3):mu(3)-[[triple bond]C(C[triple bond]C)(2)C(6)H(4)(C[triple bond]C)(2)C[triple bond]]}.
    Dalton Transactions 10/2010; 39(37):8801-11. · 3.81 Impact Factor
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    ABSTRACT: Novel [Rh(η-diene)Tp(x)] complexes of sterically encumbered Tp(x) ligands (Tp(x) = Tp(4Bo), diene = cod, 1; nbd, 2; Tp(x) = Tp(4Bo,5Me), diene = cod, 3; nbd, 4; Tp(x) = Tp(a,3Me), diene = cod, 5; nbd, 6; Tp(x) = Tp(a*,3Me), diene = cod, 7; nbd, 8) have been prepared by treatment of [Rh(η-diene)(μ-Cl)](2) with TlTp(x) (Tp(x) in general, in detail: Tp(4Bo) = hydrotris(indazol-1-yl)borate, Tp(4Bo,5Me) = hydrotris(5-methyl-indazol-1-yl)borate, Tp(a,3Me) = hydrotris(3-methyl-2H-benz[g]-4,5-dihydroindazol-2-y1)borate, Tp(a*,3Me) = hydrotris(3-methyl-2H-benz[g]indazol-2-yl)borate), and characterized by analytical and spectral data (IR, (1)H, (11)B, and (13)C NMR solution). The structures adopted by [Rh(nbd)Tp(4Bo)] 2, [Rh(cod)Tp(4Bo,5Me)] 3, [Rh(nbd)Tp(a,3Me)] 6, [Rh(nbd)Tp(a*,3Me)] 8, and [Rh(nbd)Tp(a*,3Me*)] 8* (incorporating a borotropomeric ligand), have been investigated. Low steric hindrance between the ligands in 2 and 3 permits κ(3) coordination of the pyrazolylborate while the high steric encumbrance present in 6, 8, and 8* results in κ(2) ligands. The coordination modes of the ligands to the metal have also been established by (15)N CPMAS studies of selected ligands and their corresponding Rh complexes. These spectroscopic data are in agreement with the (15)N chemical shifts obtained by using quantum-chemical methods to assist reliable assignments of the experimental values, affording new insights into the extraction of structural information concerning the hapticity (κ(2) or κ(3)) of the poly(pyrazolyl)borate ligands to the Rh metal.
    Inorganic Chemistry 10/2010; 49(23):11205-15. · 4.59 Impact Factor

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1k Citations
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Institutions

  • 1981–2014
    • University of Western Australia
      • School of Chemistry and Biochemistry
      Perth City, Western Australia, Australia
  • 2008–2012
    • University of Auckland
      • School of Chemical Sciences
      Auckland, Auckland, New Zealand
  • 1999–2011
    • University of Wollongong
      • School of Chemistry
      Wollongong, New South Wales, Australia
  • 2004–2010
    • University of Camerino
      • Dipartimento di Scienze Chimiche
      Matelica, The Marches, Italy
  • 2003–2010
    • University of Adelaide
      • • School of Chemistry and Physics
      • • Discipline of Chemistry
      Adelaide, South Australia, Australia
    • University of Carthage
      Qarţājannah, Tūnis, Tunisia
    • Prince of Songkla University
      • Department of Chemistry
      Songkhla, Changwat Songkhla, Thailand
  • 2002–2010
    • University of Strasbourg
      • • Institut de science et d'ingénierie supramoléculaires (ISIS)
      • • Laboratoire de Chimie de Coordination Organique
      Strasbourg, Alsace, France
  • 2009
    • Durham University
      • Department of Chemistry
      Durham, ENG, United Kingdom
  • 2007
    • University of North Dakota
      • Department of Chemistry
      Grand Forks, ND, United States
  • 1998–2007
    • University of Tasmania
      • School of Chemistry
      Newnham, Tasmania, Australia
  • 2006
    • University of Western Sydney
      Penrith, New South Wales, Australia
    • Dong-A University
      Tsau-liang-hai, Busan, South Korea
  • 2004–2006
    • National Institute for Environmental Studies
      • Center for Material Cycles and Waste Management Research
      Tsukuba, Ibaraki, Japan
    • Monash University (Australia)
      • School of Chemistry, Clayton
      Melbourne, Victoria, Australia
  • 2005
    • University of Sydney
      • School of Chemistry
      Sydney, New South Wales, Australia
  • 2003–2004
    • Chiang Mai University
      Amphoe Muang Chiang Mai, Chiang Mai, Thailand
  • 1990–1993
    • Griffith University
      Southport, Queensland, Australia