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ABSTRACT: The reaction of N,N,N′,N′-tetramethylethylenediamine (tmeda) and NiCl2 with the soft, Lewis acidic Hg(CN)2 and HgCl2 in ethanol formed the 2-D layer structure {(tmeda)Ni[Hg(CN)2]2}[HgCl4] (1), isostructural to the Cu(II) analogue. Complex 1 crystallizes in the tetragonal, non-centric
P[`4] \text 21P \overline{4} {\text{ }}2_{1}m space group and contains a 2-D cationic layer of {(tmeda)Ni[Hg(CN)2]2}2+ units in which the six-coordinate Ni(II) centres are bridged by four Hg(CN)2 groups and capped by a tmeda ligand. This array is interspersed with a layer of [HgCl4]2− anions, which form bridging Hg–Cl bonds with the Hg(CN)2 units. The formation of 1 is very sensitive to reaction conditions; the addition of water to the mixture yields the related “structural pitstop” 2-D array {(tmeda)Ni(H2O)[Hg(CN)2]}{[Hg(CN)Cl]2Cl2}H2O (2), in which the halide migration among Hg(II) centres is incomplete. The larger zero-field splitting D-values of 6.91(1)cm−1 for 1 vs. 2.85(4)cm−1 for 2 indicate that some weak antiferromagnetic interactions are likely present in 1. The reaction of tmeda/Cu(ClO4)26H2O with Hg(CN)2 yields [Cu(tmeda)(μ-OH)(ClO4)]2[Hg(CN)2(H2O)2][Hg(CN)2] (3) which is composed of [Cu(tmeda)(μ-OH)(ClO4)]2 dimers in which the
ClO4-\hbox{ClO}_4^{-} anions cis-bridge the copper(II) centres in the axial positions as well as bind to two adjacent Hg(CN)2 moieties; the perchlorate anion is acting as a rare η4–μ4–ClO4 ligand. N-cyano interactions also exist between the Hg(II) centres; overall, a 2-D corrugated sheet structure which stacks via Cl–O–Hg bridges to yield a 3-D array is formed. The χM
T value for 3 decreases with decreasing temperature; a maximum in χM vs. T at 20K is also observed. This is consistent with antiferromagnetic interactions within the copper(II) dimer, which were fit with the Bleaney-Bowers model to yield J=−23.1(1)cm−1, g=2.113(5) and a paramagnetic impurity P=0.017(1).
Journal of Inorganic and Organometallic Polymers and Materials 05/2012; 15(4):447-458. · 1.45 Impact Factor
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ABSTRACT: The X-ray crystal structure of di-μ-iodobis[bis(phenylphosphine)copper(I)] has been determined: R1 = 0.0460. The crystals were monoclinic, space group Cc, a = 10.625(2) Å, b = 25.115(8) Å, c = 11.361(2) Å, β = 105.929(15)°, fw = 821.28, and Z = 4. The molecular structure consists of two CuI(C6H5PH2)2 units bridged via the iodines so that each copper achieves tetrahedral coordination. Nuclear magnetic resonance data provides evidence that the phenylphosphines remain coordinated in solution but undergo rapid exchange at room temperature.
Canadian Journal of Chemistry 02/2011; 63(4):928-934. · 1.24 Impact Factor
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ABSTRACT: The synthesis and characterization of the novel selenium coronands, 1,3,7,9-tetraselenacyclododecane 1a, 1,3,7,9,13,15-hexaselenacyclooctadecane 2a, the corresponding β-gem-dimethyl derivatives 1b, 2b, and 1,5,9,13-tetraselenacyclohexadecane 3, and 1,5,9,13,17,21-hexaselenacyclotetracosane 4 are described. X-ray crystallographic analysis of 1a reveals three independent molecules that exist in two distinct conformations, one molecule having approximate two-fold symmetry together with two molecules (of similar conformation) each having crystallographic symmetry. The conformations are denoted as [3333] or [66]. Whereas one resembles that of cyclododecane and tetrathia-12-crown-4 with respect to torsion angles, the other resembles that of tetraoxa-12-crown-4. The solid state CP-MAS 77Se and 13C nmr spectra are interpreted in light of the crystallographic information. Crystal structure: formula Se4C8H16; fw = 428.05; monoclinic, P21/c; Z = 8; a = 15.823(2) Å, b = 5.534(1) Å, c = 27.962(5) Å, β = 92.26(1)°; V = 2446.6 Å3; T = 200 K; R = 0.027 for 2162 observed data (I ≥ 2.5σ(I)).
Canadian Journal of Chemistry 02/2011; 66(11):2956-2958. · 1.24 Impact Factor
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ABSTRACT: Room temperature and low-temperature (110–140 K) powder diffractograms have been obtained for the polymeric compounds [Cu(4-Xpz)2]x (where X = H, CH3, Cl, and Br), and values of the unit cell parameters (orthorhombic, space group Ibam) a, b, and c have been obtained at both high and low temperatures. A single crystal X-ray diffraction study of the X = H compound at 116 K was completed and the results compared with a published study done at room temperature. The structures of these complexes involve extended chains of pyrazolate-bridged copper ions extending along the c crystallographic axis. The X-ray studies indicate little change in the c parameter with decreasing temperature and small but significant changes in the a or b parameters reflecting changes in interchain packing. This study permits some evaluation of how structural parameters are affected by these variations in interchain packing and how these variations may be affecting the magnitude of magnetic exchange in the compounds.
Canadian Journal of Chemistry 02/2011; 71(3):331-334. · 1.24 Impact Factor
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ABSTRACT: Bis(hydroxamido)hydroxooxovanadate has been found to undergo favourable condensation reactions with simple peptides such as glycylglycine, glycylglycylglycine, or glycyltyrosine to afford, in each case, three products in the approximate ratio 1:3.5:0.2. The three products had the same ligand stoichiometry and, in the case of glycylglycine, an overall formation constant of 3.3 × 103 M−1 for the addition of GlyGly to bis(hydroxamido)vanadate. The 51V chemical shift range of the products (close to −850 ppm) overlaps that of the starting complexes and the products may well have a coordination geometry similar to the parent complexes. The chemical shifts observed for these materials are in the range of chemical shifts observed for peroxovanadium complexes. A crystalline monomeric complex with a single glycylglycinato ligand was obtained and its crystal structure determined. The complex is zwitterionic and has a pentagonal bipyramidal coordination at vanadium with the glycine-NH2 functionality coordinated in the plane of the two hydroxyalamine ligands and the amido carbonyl oxygen in the apical position. Some comparisons with peroxovanadium complexes are drawn. Crystal structure of V(O)(ONH2)2(GlyGly)•H2O: monoclinic, space group Cc; Z = 4; a = 9.1340(9) Å; b = 16.3355(15) Å; c = 7.1149(6) Å; β(°) = 103.020(7); V = 1034.31 Å3; T = 295 K; RF = 0.21 for 2513 data (I0 ≥ 2.5σ(I0)) and 197 variables. Keywords: vanadate, hydroxylamine, N-methylhydroxylamine, oxobis(hydroxamido)glycylglycinatovanadium(V), peptide complex, glycylglycine, 51V NMR, crystal structure.
Canadian Journal of Chemistry 02/2011; 75(2):183-191. · 1.24 Impact Factor
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ABSTRACT: 51V nuclear magnetic resonance spectroscopy has been utilized in the investigation of the reactions of vanadate with N,N-dimethylhydroxylamine in aqueous medium. The major components of the reaction products were mono- and bisliganded mononuclear vanadate compounds with 51V chemical shifts near −630 and −740 ppm, respectively. Variation of the concentration of the reactants enabled the determination of stoichiometry and formation constants of the products. The two major signals near −740 ppm were assigned to two stereoisomers of a bisligand product. The proton stoichiometrics and pKa values of the major products were determined from pH variation studies. A crystalline product of the type [V(O)(ONMe2)2]2O was isolated from the reaction of vanadate with dimethylhydroxylamine and its structure determined from X-ray diffraction studies. The compound possesses a dimeric oxo-bridge structure with a six-coordinate vanadium core. The arrangement about each vanadium may be described as approximately tetrahedral considering the center of the N—O bond in each dimethylhydroxamide ligand as one vertex. Hydrolysis of the crystalline solid in D2O provided two isomers that corresponded to the two bisligand products. A variable temperature 1H NMR study in D2O and 50% D2O/(CD3)2CO mixture revealed the existence of reasonably fast chemical exchange between the two predominant isomers. The nature of coordination of these and related compounds is discussed. Crystal structure of [V(O)(ONMe2)2]2O: orthorhombic, space group P22121;Z = 2;a = 7.0955(9) Å; b = 10.2313(12) Å; c = 11.5942(11) Å; V = 841.69 Å3; T = 213 K; RF = 0.021 for 1141 data (I0 ≥ 2.5σ(I0) ) and 137 variables. Keywords: bis(N,N-dimethylhydroxamido)hydroxooxovanadate, vanadate, dimethylhydroxylamine, vanadium NMR, aqueous equilibria, peroxovanadate.
Canadian Journal of Chemistry 02/2011; 75(4):429-440. · 1.24 Impact Factor
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ABSTRACT: Base-promoted hydrolysis kinetics for N-(4-nitrobenzoyl)pyrrole (1) have been measured as a function of buffer concentration at several pH values at 25°C. In addition carbonyl-18O exchange kinetics have been determined at a single pH value (9.48) as a function of 1,4-diazobicyclo[2.2.2]octane (DABCO) concentration. At zero buffer concentration the measured ratio of 18O exchange to hydrolysis (kex/khyd) is approximately 0.04, and this value increases and finally levels off at about 0.23 as the DABCO concentration is increased. These observations are consistent with the buffer acting as a general-base to catalyze both the attack of water to generate an anionic tetrahedral intermediate (To-) and the breakdown of To- to give hydrolysis products.Key words: amide, hydrolysis, catalysis, general-base, tetrahedral intermediate.
Canadian Journal of Chemistry 02/2011; 76(10):1410-1417. · 1.24 Impact Factor
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ABSTRACT: Reaction of β-mercaptoethanol with vanadate under slightly alkaline conditions provided a crystalline complex that was characterized by X-ray diffraction and FTIR spectroscopy. The complex was dimeric in structure with a central [VO]2 core and a pentacoordinate, crudely trigonal bipyramidal arrangement about each vanadium atom with a sulphur occupying a pseudo-axial position. A single 51V NMR signal was observed for this complex when dissolved in water, chloroform or acetonitrile. A large influence of acetonitrile on the vanadium chemical shift suggested the possibility of reaction with acetonitrile. FTIR showed the presence of two complexes in acetonitrile solution but only one in chloroform or water. Mixed solvent studies were carried out in an effort to further characterize the solution complexes. Crystal structure of [{VO2(OC2H4S)}2][NEt4]2: monoclinic, space group P21/n,. a = 8.3451(17), b = 16.954(4), c = 10. 2064(25) Å; β = 101. 271(18)°; V = 1416.2 Å3; Z = 2; RF = 0.048 for 1355 data (Io 2..5σ (Io) and 147 variables.Key words: mercaptoethanol, vanadate, vanadium NMR, X-ray diffraction, FTIR, thiolate.
Canadian Journal of Chemistry 02/2011; 77(12):2088-2094. · 1.24 Impact Factor
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Michael J Katz,
Vladimir K Michaelis,
Pedro M Aguiar,
Renante Yson,
Haiyan Lu,
Harini Kaluarachchi, Raymond J Batchelor,
Georg Schreckenbach,
Scott Kroeker,
Howard H Patterson,
Daniel B Leznoff
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ABSTRACT: The reaction of Pb(ClO4)2 x xH2O, an ancillary ligand L, and two equivalents of Au(CN)2(-) gave a series of crystalline coordination polymers, which were structurally characterized. The ligands were chosen to represent a range of increasing basicity, to influence the stereochemical activity (i.e., p-orbital character) of the Pb(II) lone pair. The Pb(II) center in [Pb(1,10-phenanthroline)2][Au(CN)2]2 (1) is 8-coordinate, with a stereochemically inactive lone pair; all 8 Pb-N bonds are similar. The Au(CN)2(-) units propagate a 2-D brick-wall structure. In [Pb(2,2'-bipyridine)2][Au(CN)2]2 (2), the 8-coordinate Pb(II) center has asymmetric Pb-N bond lengths, indicating moderate lone pair stereochemical activity; the supramolecular structure forms a 1-D chain/ribbon motif. For [Pb(ethylenediamine)][Au(CN)2]2 (3), the Pb(II) is only 5-coordinate and extremely asymmetric, with Pb-N bond lengths from 2.123(7) to 3.035(9) A; a rare Pb-Au contact of 3.5494(5) A is also observed. The Au(CN)2(-) units connect the Pb(ethylenediamine) centers to form 1-D zigzag chains which stack via Au-Au interactions of 3.3221(5) A to yield a 2-D sheet. (207)Pb MAS NMR of the polymers indicates an increase in both the chemical shielding span and isotropic chemical shift with increasing Pb(II) coordination sphere anisotropy (from delta iso = -2970 and Omega = 740 for 1 to delta iso = -448 and Omega = 3980 for 3). The shielding anisotropy is positively correlated with Pb(II) p-character, and reflects a direct connection between the NMR parameters and lone-pair activity. Solid-state variable-temperature luminescence measurements indicate that the emission bands at 520 and 494 nm, for 1 and 2, respectively, can be attributed to Pb --> L transitions, by comparison with simple [Pb(L)2](ClO4)2 salts. In contrast, two emission bands for 3 at 408 and 440 nm are assignable to Au-Au and Pb-Au-based transitions, respectively, as supported by single-point density-functional theory calculations on models of 3.
Inorganic Chemistry 07/2008; 47(14):6353-63. · 4.60 Impact Factor
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ABSTRACT: An elaborate coordination polymer is formed using the weak Lewis-base [Au(CN)4]- coupled to a Jahn−Teller distorted CuII ion. Such structural complexity is inaccessible if a stronger structure-directing bonding interaction is present, as in the simpler NiII analog.
09/2007;
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ABSTRACT: In a series of iron(III) halide complexes of the form {FeX[MesN(SiMe(2))]2O}2 (Mes = mesityl; X = Cl, Br, I), the ancillary diamidosilylether ligand can either chelate to one metal or instead bridge two metal centers, as a function of the halide coligand. The complexes are prepared from diamidosilyletheriron(II) precursors, which are oxidized with iodine, benzyl bromide, or PhICl2 to yield the appropriate iron(III) halide. The bromide analogue can also be synthesized by reacting the iron(II) precursor with a bromonium transfer agent (stabilized by adamantylideneadamantane). The latter reaction may proceed via an iron(IV) intermediate, which can oxidize the normally noncoordinating, inert [B(ArF)4]- counteranion [ArF = 3,5-(CF3)2Ph].
Inorganic Chemistry 02/2007; 46(2):366-8. · 4.60 Impact Factor
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Angewandte Chemie International Edition 02/2007; 46(46):8804-7. · 13.45 Impact Factor
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ABSTRACT: The coordination polymer Pb(H2O)[Au(CN)2]2 (1) was synthesized by the reaction of KAu(CN)2 and Pb(NO3)2. The structure contains 1-D chains of lead(II)-OH2 linked via Au(CN)2(-) moieties, generating a 2-D slab; weak aurophilic interactions of 3.506(2) and 3.4885(5) A occur within and between slabs. The geometry about each lead(II) is bicapped trigonal prismatic, having six N-bound cyanides at the prism vertices and waters at two of the faces. Dehydration at 175 degrees C yields microcrystalline Pb[Au(CN)2]2 (2), which, along with 1, was examined by 13C, 15N, 1H, and 207Pb solid-state NMR methods. Two 15N resonances are assigned to the mu2-bridging and hydrogen-bonding cyanides in 1. Upon dehydration, the 207Pb NMR spectrum becomes axially symmetric and yields a reduced shielding span, indicating higher site symmetry, while the 13C and 15N spectra reveal a single cyanide. Although no single-crystal X-ray structure of 2 could be obtained, a structure is proposed on the basis of the NMR and X-ray powder data, consisting of a lead(II) center in a distorted square-prismatic environment, with cyanides present at each corner. The birefringence of single crystals of 1 is found to be 7.0 x 10(-2) at room temperature. This value is large compared to that of most optical materials and can be attributed to the anisotropy of the 2-D slabs of 1, with all CN bonds aligned in the same direction by the polarizable lead(II) center.
Journal of the American Chemical Society 04/2006; 128(11):3669-76. · 9.91 Impact Factor
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ABSTRACT: A Cu(I)/Cu(II)/Zn(II) mixed-valent [Cu(en)2][Zn(NC)4(CuCN)2] polymer, which has a 2-D layer structure with six structurally inequivalent cyanides in four distinct bonding modes, has been prepared; structurally informative 13C and 15N MAS NMR spectra of this paramagnetic system are readily observable.
Chemical Communications 03/2006; · 6.17 Impact Factor
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ABSTRACT: Two polymorphic products, [[Cu(tmeda)(mu-OH)}2Au(CN)4][Au(CN)4] (1) and [Cu(tmeda)(mu-OH)Au(CN)4]2 (2), were synthesized from {Cu(tmeda)(mu-OH)}(2)X(2) (tmeda = N,N,N',N'-tetramethylethylenediamine, X = ClO4-, BF4-) and 2 equiv of K[Au(CN)4], and their X-ray structures were determined. Both compounds have [Cu(tmeda)(mu-OH)}2(2+) dimers with [Au(CN)4]- units bound in the axial positions. However, in 1, two trans N-donor cyanides of each [Au(CN)4]- unit bind to adjacent copper(II) dimers, forming a 1-D chain, whereas complex 2 is molecular, with two mono-coordinated [Au(CN)4]- units. The 1-D polymorph 1 is formed from aqueous solution, while the molecular polymorph 2 is obtained with X = BF4- in methanol. The polymorphs have slightly different Cu-O-Cu angles, a key magnetostructural parameter, such that the 1-D chain 1, with an angle of 96.6(2) degrees, shows ferromagnetic interactions with 2J = +57.5 cm(-1) and g = 2.097, whereas the molecular complex 2, with an angle of 98.92(17) degrees, shows antiferromagnetic interactions with 2J = -143.6 cm(-1) and g = 2.047. A similar Cu(II) complex, [[Cu(tmeda)(mu-OH)]2Au(CN)4][ClO4].MeOH (3), was synthesized in methanol when X = ClO4-, in which the [Au(CN)4]- unit bridges the two Cu(II) centers within the dimer in an intramolecular fashion via cis N-donor cyanides. The average Cu-O-Cu angle of 98.4(2) degrees in 3 generates antiferromagnetic interactions with 2J = -64.8 cm(-1) and g = 2.214. Complexes 1-3 represent the first examples of [Cu(tmeda)(mu-OH)]2(2+) dimers with Cu-O-Cu angles under 100 degrees, thereby extending the range of 2J coupling constants for this moiety from 149 to 566 cm(-1). The switch to ferromagnetic interactions in 1 as a result of the coordinating, bridging [Au(CN)4]- anion suggests that cationic, dinuclear moieties that are typically antiferromagnetically coupled may, with an appropriate coordinating counterion, become ferromagnetic units.
Inorganic Chemistry 03/2006; 45(4):1757-65. · 4.60 Impact Factor
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Inorganic Chemistry - INORG CHEM. 01/2006; 45(4):1757-1765.
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ABSTRACT: The high-yield synthesis, spectroscopic and structural determination of three new uranium(IV) and thorium(IV)ate complexes supported by three different diamido ether ligands are reported. The reaction of Li2[2,6-iPr2PhN(CH2CH2)]2O (Li2[DIPPNCOCN]) with 1 equiv. of UCl4 in THF generates [DIPPNCOCN]UCl3Li(THF)2(1), while reaction in toluene/ether gives salt-free [DIPPNCOCN]UCl2.1/2C7H8(2), which was identified by paramagnetically shifted 1H NMR. Reaction of 0.5 equiv. of {[tBuNON]UCl2}2([tBuNON]=[(CH3)3CN(Si(CH3)2)]2O2-) with 3.5 equiv. LiI in toluene and a minimal amount of THF results in [tBuNON]UI3Li(THF)2(3) and is very similar in structure to 1. {[MesNON]ThCl3Li(THF)}2(4), a dimeric complex with a Th2Li2Cl6 core, is prepared by reaction of Li2[2,4,6-Me3PhN(Si(CH3)2)]2O (Li2[MesNON]) with ThCl4 in THF. The analogous reaction in toluene did not yield the salt-free complex but rather a sterically crowded diligated compound, [MesNON]2Th (5), which was also structurally characterized. Complex 5 was prepared rationally by reacting 2 equiv. Li2[MesNON] with ThCl4 in toluene. The reaction of 1 and 3 with 2 equiv. of LiCH2Si(CH3)3 generates the stable, salt-free organoactinides [DIPPNCOCN]U(CH2Si(CH3)3)2(6) and [tBuNON]U(CH2Si(CH3)3)2(7). Complex 6 was structurally characterized. These reactions illustrate the viability of ate complexes as useful synthetic precursors.
Dalton Transactions 10/2005; · 3.84 Impact Factor
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ABSTRACT: The dilithio salts of two chelating diamidosilylether ligands undergo a retro-Brook rearrangement from oxygen to the amido-nitrogen, thereby directly yielding a new mixed-donor amido/amino/siloxo ligand. When reacted with chromium(II), siloxo-bridged dimers and a very strong eta(2)-(N,C(ipso)) arylamido interaction are featured.
Dalton Transactions 08/2005; · 3.84 Impact Factor
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ABSTRACT: Two polymorphs of an [Au(CN)2]-based coordination polymer, Cu[Au(CN)2]2(DMSO)2, one green (1) and one blue (2), have been identified. In polymorph 1, alternation of five-coordinate Cu(II) and [Au(CN)2]- units generates 1-D chains, while 2-D corrugated sheets are obtained in polymorph 2, which contains six-coordinate Cu(II) centers. Both polymorphs form 3-D networks by virtue of aurophilic interactions of 3.22007(5) A and 3.419(3) A, respectively, and show similar weak antiferromagnetic coupling, but have different thermal decomposition temperatures. They both show vapochromic properties and, importantly, despite their significantly different solid-state structures, the vapochromic behavior of the two polymorphs is essentially identical. Upon solvent exchange, both polymorphs convert to the same Cu[Au(CN)2]2(solvent)x complex (solvent = H2O, CH3CN, dioxane, N,N-dimethylformamide, pyridine, NH3). The Cu[Au(CN)2]2(DMF) and Cu[Au(CN)2]2(pyridine)2 complexes have very similar 2-D square grid structures, comparable to that of 2. The solvent molecules adsorbed by Cu[Au(CN)2]2 bind to the Cu(II) centers, thereby altering the visible spectrum associated with the Cu(II) chromophores and the number and frequency of the nu(CN) as well. The network-stabilizing gold-gold interactions and the flexible coordination sphere of Cu(II) probably facilitate reversible solvent exchange at room temperature.
Journal of the American Chemical Society 01/2005; 126(49):16117-25. · 9.91 Impact Factor
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ABSTRACT: In the reaction of organic monocationic chlorides or coordinatively saturated metal-ligand complex chlorides with linear, neutral Hg(CN)(2) building blocks, the Lewis-acidic Hg(CN)(2) moieties accept the chloride ligands to form mercury cyanide/chloride double salt anions that in several cases form infinite 1-D and 2-D arrays. Thus, [PPN][Hg(CN)(2)Cl].H(2)O (1), [(n)Bu(4)N][Hg(CN)(2)Cl].0.5 H(2)O (2), and [Ni(terpy)(2)][Hg(CN)(2)Cl](2) (4) contain [Hg(CN)(2)Cl](2)(2-) anionic dimers ([PPN]Cl = bis(triphenylphosphoranylidene)ammonium chloride, [(n)Bu(4)N]Cl = tetrabutylammonium chloride, terpy = 2,2':6',6' '-terpyridine). [Cu(en)(2)][Hg(CN)(2)Cl](2) (5) is composed of alternating 1-D chloride-bridged [Hg(CN)(2)Cl](n)(n-) ladders and cationic columns of [Cu(en)(2)](2+) (en = ethylenediamine). When [Co(en)(3)]Cl(3) is reacted with 3 equiv of Hg(CN)(2), 1-D [[Hg(CN)(2)](2)Cl](n)(n-) ribbons and [Hg(CN)(2)Cl(2)](2-) moieties are formed; both form hydrogen bonds to [Co(en)(3)](3+) cations, yielding [Co(en)(3)][Hg(CN)(2)Cl(2)][[Hg(CN)(2)](2)Cl] (6). In [Co(NH(3))(6)](2)[Hg(CN)(2)](5)Cl(6).2H(2)O (7), [Co(NH(3))(6)](3+) cations and water molecules are sandwiched between chloride-bridged 2-D anionic [[Hg(CN)(2)](5)Cl(6)](n)(6n-) layers, which contain square cavities. The presence (or absence), number, and profile of hydrogen bond donor sites of the transition metal amine ligands were observed to strongly influence the structural motif and dimensionality adopted by the anionic double salt complex anions, while cation shape and cation charge had little effect. (199)Hg chemical shift tensors and (1)J((13)C,(199)Hg) values measured in selected compounds reveal that the NMR properties are dominated by the Hg(CN)(2) moiety, with little influence from the chloride bonding characteristics. delta(iso)((13)CN) values in the isolated dimers are remarkably sensitive to the local geometry.
Inorganic Chemistry 11/2004; 43(21):6557-67. · 4.60 Impact Factor
