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1.
The complex Pt(bph) (CO) 2 crystallizes in the space group Cmcm with a = 18.647(6), B = 9.566(2) and C = 6.4060(5) Å. The geometry of the molecule is slightly distorted from square planar with a Pt---C(CO) bond distance of 1.98(2) Å and a Pt---C(bph) bond distance of 2.04(2) Å. The Pt(bph)(CO) 2 complex serves as a precursor for the preparation of a wide variety of Pt(bph)X 2 complexes, where X = monodentate ligands such as acetonitrile, pyridine, etc., and X 2 = bidentate ligands such as bypyridine, 1,10-phenanthroline, etc. In the solid state, the complex exhibits a green color, but when ground with an alkali metal salt turns deep blue to purple. In CH 2Cl 2, the color disappears but optical transitions are observed at 271 nm (2.7 × 10 4 M −1 cm −1), 303 nm (1.1 × 10 4 M −1 cm −1) and 330 nm (5.5 × 10 3 M −1 cm −1). The complex is a weak emitter exhibiting a structured spectrum in CH 2Cl 2 at r.t. with maxima located at 562 and 594 nm and an emission lifetime of 3.1 μs when excited at 337 nm. 相似文献
2.
New partially N-hydroxyethylated 14-membered tetraaza macrocycles 1,8-bis(2-hydroxyethyl)-3,5,7,7,10,12,14,14-octamethyl-1,4,8,11-tetraazacyclotetradecane (L 2) and 1-(2-hydroxyethyl))-3,5,7,7,10,12,14,14-octamethyl-1,4,8,11-tetraazacyclotetradecane (L 3) have been synthesized selectively by the one-step reaction of 2,5,5,7,9,12,12,14-octamethyl-1,4,8,11-tetraazacyclotetradecane (L 1) with 2-hydroxyethyl bromide. The complexes [NiL 3] 2+, [CuL 2] 2+, and [CuL 3] 2+ have been prepared and characterized. The complex [CuL 2](ClO 4) 2 has a square-pyramidal coordination geometry with one apical oxygen atom; only one of the two hydroxyethyl groups is coordinated to the metal ion. Electronic absorption spectra of [CuL 3](ClO 4) 2 containing one hydroxyethyl pendant arm indicate that the geometry is similar to that of [CuL 2](ClO 4) 2. Unexpectedly, the nickel(II) complex [NiL 3](ClO 4) 2 has a severely distorted trigonal bipyramidal coordination geometry with the oxygen atom of the pendant arm at the equatorial position. The Ni---O bond distance of the nickel(II) complex is shorter, or not longer, than the Ni---N bond distances. The ligand in [CuL 2] 2+ is in the RRSS ( trans-III) configuration, as usual, whereas that in [NiL 3] 2+ has the RRRR ( trans-V) conformation. The coordination geometry and properties of [NiL 3] 2+ are quite different from those reported for other related nickel(II) complexes containing one functional pendant arm. 相似文献
3.
The ligand N, N′-bis[2,2-dimethyl-4-(2-hydroxyphenyl)-3-aza-3-buten] oxamide with two identical coordination sites reacts with copper ions in its tetradeprotonated form to yield the dinuclear complex [Cu 2(C 24H 26N 4O 4)]·H 2O. The structure of this compound has been determined by the X-ray diffraction method. The crystals are orthorhombic with a = 11.744(1), B = 16.369(2), C = 26.340(3) Å, V = 5064(1) Å 3, Z = 8, space group Pbca. The oxamide is in a trans conformation with two different environments for the copper centres, a (4 + 1) coordination mode for the first one and a square planar environment for the other one. The water molecule is not directly bound to a copper centre, but involved in hydrogen bonding with the two oxygen atoms of an N 2O 2 coordination site. Indeed, extra coordination comes from a phenolic oxygen atom belonging to an adjacent dinuclear unit. Static susceptibility measurements point to a strong intrapair antiferromagnetic exchange interaction of 2 J = −520(±4) cm −1 and possibly an interpair ferromagnetic exchange interaction of 10(±5) cm −1. 相似文献
4.
The title compoud, [TlMe 2(HL)(H 2O)] (HL = monoanion of pyridoxal thiosemicarbazone), crystallizers in the triclinic space group
, No. 2). The HL −anion coordinates to the thallium atom, in an unusual mode through the S atom (Tl-S = 2.832(1) Å), and also forms a weak bond with the metal atom of a neighbouring molecule to make an asymmetric bridge (Tl′…S = 3.190(1) Å). The acidic proton retained in the thiosemicarbazonato anion is located on the oxygen of the phenolic hydroxyl group. The water molecule is only 2.630(4) Å from the metal, suggesting a rather strong bond that contrasts with the long distance between the thallium and the phenolic oxygen (Tl…O(1)′ = 3.124(4) Å). If both strong and weak intermolecular interactions are taken in account, the metal has distorted octahedral coordination with the methyl groups in apical positions. The solid state IR spectrum and 1H, 13C and 205Tl NMR spectra in DMSO solution are also discussed. 相似文献
5.
The first crystal and molecular structure of a transition metal complex containing 1,2-dithiocroconate (1,2-dtcr, dianion of 1,2-dimercaptocylopent-1-ene-3,4,5-trione), [Cu(bpca)(H 2O)] 2[Cu(1,2-dtcr) 2]·2H 2O (where bpca is the bis(2-pyrdidylcarbonyl)amide anion), has been determined by single crystal X-ray diffraction methods. The compound crystallizesin the monoclinic syste, space group P2 1/ c, with a = 11.661(3), b = 20.255(6), c = 8.265(3) Å, ß = 107.26(2)° and Z = 2. The structure is formally built of [Cu(1,2-dtcr) 2] 2− and [Cu(bpca)(H 2O)] + ions and water of hydration. The copper atom of the anion is situated at a crystallographic inversion centre, bonded to four sulfur atoms in a planar, approximately square arrangement. In the cation the copper equatorial plane is formed by the three nitrogen atoms of the bpca ligand and a water oxygen atom. In addition there is a very weak axial bond to one of the sulfur atoms of a 1,2-dtcr ligand in the anion. Through these latter weak bonds each anion is connected to, and sandwiched between, two cations, resulting in neutral, trinuclear, centrosymmetric formula units. The triple-decker molecules are arranged in stacks along the crystallographic a-axis creating close contacts between the terminal copper atoms and bpca groups of the neighbouring molecules. This intermolecular interaction is, however, too weak to define the structure as a chain compound. The distance between adjacent copper atoms within the trinuclear unit is 4.189(1) Å, while the shortest intra-stack metal-metal separation between terminal copper atoms is 5.281(1) Å. Variable-temperature magnetic susceptibility measurements in the temperature r.2–140 K reveal that a Curie law is followed; with three non-interacting copper(II) ions in the formula unit. 相似文献
6.
The first 1:2 metal complexes of 2-(2′-pyridyl)quinoxaline (L) have been isolated. The physical and spectroscopic characteristics of the compounds [MCl 2L 2] (M = Ni, Cu, Cd) and [Cu IL 2](PF 6) are described. The structure of the copper(I) complex has been determined by X-ray diffraction methods. Crystals are orthorhombic, space group Pcnb with A = 11.014(2), B = 12.886(2), C = 17.806(4) Å, V = 2527.1(9) Å 3 and Z = 4. Refinement of the structure gave a final R factor of 0.046 ( Rw = 0.041) for 814 unique reflections having I > 2.0σ( I). The ligand L acts as a bidentate chelate, the ligated atoms being the pyridine nitrogen and the nearest quinoxaline nitrogen. The structure of [CuL 2] + consists of a distorted tetrahedral arrangement around the copper(I) atom with Cu---N bond lengths of 2.023(6) and 2.059(5) Å and the N---Cu---N angle of the chelating ligand equal to 80.6(2)°. A monomeric trans pseudo-octahedral stereochemistry is assigned for the [MCl 2L 2] complexes. 相似文献
7.
(3-Trimethylsilyl-pyridine-2-thiolato-S,N)copper(I), [Cu(3-Me 3Sipyt)], was obtained by electrochemical oxidation of copper metal in an acetonitrile solution of the neutral ligand. The compound is tetrameric and the four copper atoms are arranged with distorted tetrahedral geometry, each copper atom being trigonally coordinated to one nitrogen and two sulfur atoms of three different ligands. Crystal data: 14 1/ a, a=14.608(2), C=19.366(4) Å, V=4133(2), Å, Z=4, Dcalc=1.581 g cm −3, R=0.0397 for 848 reflections. 相似文献
8.
The reactions of cadmium halides with the 15-membered macrocyclic crown ethers, 15-crown-5 and benzo-15-crown-5, have been carried out and six new complexes have been isolated and structurally characterized. Metal to ligand stoichiometries of 1:1, 2:1, 3:1 and 3:2 have been observed with a variety of different formulations. Examples of charge separated ion pairs ([(NH 4)(benzo-15-crown-5) 2] 2[Cd 2I 6]), halogen bridged monomers, dimers or polymers ([Cd(15-crown-5)(OHMe)(μ-Br)CdBr 3], [Cd(15-crown-5)(μ-Br) 2CdBr(μ-Br)] 2(isolated from the same reaction mixture) and [(CdCl 2) 2CdCl 2(15-crown-5)] n), and hydrogen bonded finite chains or polymers ([(Cd(OH 2) 2(15-crown-5)][CdI 3(OH 2)] 2·2(15-crown-5)·2CH 3CN and [CdI 2(OH 2) 2(THF)]·benzo-15-crown-5) have been isolated. Three different types of 15-crown-5 coordination modes have been observed in these complexes. In-cavity coordination resulting in pentagonal bipyramidal geometries about Cd 2+ was observed in [(CdCl 2) 2CdCl 2(15-crown-5)] n, [Cd(15-crown-5)(OHMe)(μ-Br)CdBr 3], and [Cd(OH 2) 2(15-crown-5)][CdI 3(OH 2)] 2·2(15-crown-5)·2CH 3CN, [Cd(15-crown-5)(μ-Br) 2CdBr(μ-Br)] 2 displays out-of-cavity coordination with one etheric donor distorted into an axial position of a distorted pentagonal bipyramid. The third coordination mode is secondary sphere coordination via hydrogen bonding which is observed for [Cd(OH 2) 2(15-crown-5)][CdI 3(OH 2)] 2·2(15-crown-5)·2CH 3CN. The good fit of Cd 2+ within the cavity of 15-crown-5 results in shorter bonding contacts and a more narrow distribution in Cd---O values (2.273(7)-2.344(6) Å) than observed for cadmium halide complexes of 18-crown-6 (Cd---O = 2.69(1)–2.81(1) Å). 相似文献
9.
Electrospray mass spectrometry (ESMS) has been used to investigate the relative ligand properties of the triphenylpnictogen ligands EPh 3 (E=P, As, Sb and Bi) towards silver(I) and copper(I) ions. It is found that the preferred species formed increase in coordination number from two for PPh 3 in [Ag(PPh 3) 2] + to four for SbPh 3 in [Ag(SbPh 3) 4] +, consistent with the decreasing donor ligand ability and increasing metal –E bond length in the series PPh 3–AsPh 3–SbPh 3. With BiPh 3, the spectra were complex, suggesting considerable decomposition. These studies also suggest that silver(I) and copper(I) ions will have widespread utility in the characterisation of tertiary stibine ligands, as has been described previously for phosphines and arsines. These studies demonstrate the power of the ESMS technique in determining the donor properties of a related series of ligands, and this information is of significance in coordination chemistry. 相似文献
10.
The mononuclear manganese(III) complexes [C 5H 10NH 2][MnL 2] [L 2−=a substituted N-(2-hydroxybenzyl)glycinate (hbg 2−) viz. 3,5-dibromo- (3,5-Br-hbg 2−), 3,5-dichloro- (3,5-Cl-hbg 2−), 3-methyl-5-chloro- (3,5-Me,Cl-hbg 2−), 5-bromo- (5-Br-hbg 2−), 5-chloro- (5-Cl-hbg 2−), 5-nitro- (5-NO 2-hbg 2−) or N-(5-nitro-2-hydroxybenzyl)sarcosine (5-NO 2-hbs 2−)] have been synthesised by reaction of the appropriate ligand with manganese(II) perchlorate under ambient conditions in a 2:1 molar ratio using piperidine as base. The structures of three of these complexes, [C 5H 10NH 2][Mn(3,5-Cl-hbg) 2] (2), [C 5H 10NH 2][Mn(5-NO 2-hbg) 2] (6) and [C 5H 10NH 2][Mn(5-NO 2-hbs) 2] (7) have been elucidated by single-crystal X-ray crystallography and each displays two similar, independent [MnL 2] − ions in the asymmetric unit linked via piperidinium cations through hydrogen bonding. The ligands co-ordinate in a facial tridentate fashion with the three donor atoms being the phenolate and carboxylate oxygens and the amine nitrogen. The geometry at the Mn centres is compressed rhombic octahedral consistent with a pseudo-Jahn–Teller compression along the Mn–O(phenolate) axis. Mean bond lengths are in the ranges 1.886–1.889 Å for the Mn–O(phenolate), 2.062–2.125 Å for the Mn–O(carboxylate) and 2.091–2.184 Å for the Mn–N(amine) distances. The magnetic susceptibility and electronic and IR spectroscopic data are discussed with reference to the crystal structures. 相似文献
11.
Based on the new ligand bis(1-methyl-2-benzimidazolyl) propane (abbreviated as mtbz) several new copper(II) coordination compounds have been prepared and characterized structurally and spectroscopically. Two representative compounds, i.e. [Cu 2(mtbz) 2(CH 3) 2- (CF 3SO 3)](CF 3SO 3) (1) and [Cu 2(mtbz) 2(CH 3O) 2](ClO 4) 2 (4) were characterized structurally by X-ray diffraction. Crystal data for 1: monoclinic, space group P2 1/ c, a=13.6585(5), B=39.981(3), C=20.919(1) Å, β=125.98(1)°, Z=8. Crystal data for 4: monoclinic, space group P2 1/ c, a=13.115(2), B=9.523(2), C=17.908(4) Å, β=111.71(1)°, Z=2. Structures 1 and 4 each consist of a dinuclear unit with bridging methoxo groups and one ligand linked to each copper via an N atom. Structure 1 (which consists of two dinuclear, crystallographically independent, but chemically identical units) has the two copper atoms bridged by a triflate anion, providing each copper atom a square-pyramidal coordination, while the copper atoms in structure 4 have an almost a square-planar geometry. The Cu---Cu distances (Å) within the dinuclear units are: 1, 2.9775(13), 2.9751(13); 4, 2.9872(16); the Cu---O---Cu bridging angles (°) are: 1, 101.7(3), 101.7(3), 100.9(3), 102.1(3); 4, 103.2(2). The mid-IR section focused on the vibrations of the triflate anion reveals interesting results concerning the assignments of that anion related to the vas(S---O) band. Characteristic Cu---O vibrations in the far-IR section were found at 386 and 230 cm −1 for the methoxo-bridged and 454 and 332 cm −1 for the ethoxo-bridged compounds. These dinuclear species are EPR silent, and only a weak signal of monomeric impurities is observed. They also show a diamagnetic behavior below room temperature. 相似文献
12.
The reactions of silver perchlorate and tetraiodoethylene in different solvents, namely, benzene and toluene, isolated two silver(I)–iodocarbon complexes, [Ag(C 2I 4)(C 6H 6) 2(ClO 4)] (1) and [Ag(C 2I 4)(ClO 4)] (2). Both compounds contain intact iodoalkenes which coordinate via σ-donation of a halogen lone pair and retain their carbon–iodine bonds. Owing to the participation of the benzene molecules in coordination, complex 1 is found to be a discrete monomer in which the five-coordinate geometry of the silver ion is comprised of two benzene molecules, one C 2I 4 group and one perchlorate ion. In contrast, the unsaturated coordination environment of the metal ion in 2 is filled by the second iodocarbon group leading to a two-dimensional framework. The coordinated tetraiodoethylene molecules involve severe twisting of the C=C double bond, causing the C=C stretching band to move to a lower frequency. 相似文献
13.
The hydrothermal reactions of (Ph 4P)[VO 2Cl 2] and H 2C 2O 4 at 150 and 125°C yield (Ph 4P) 2[V 2O 2(H 2O) 2(C 2O 4) 3]·4H 2O (1) and (Ph 4P)[VOCl(C 2O 4)] (2), respectively. The structure of the molecular anion of 1 consists of a binuclear unit of oxovanadium(IV) octahedra bridged by a bisbidentate oxalate group. The VO 6 coordination geometry at each vanadium site is defined by a terminal oxo group, an aquo ligand, and four oxygen donors — two from the bisbidentate bridging oxalate and two from the terminal bidentate oxalate. The structure of 2 consists of discrete Ph 4P + cations occupying regions between [VOCl(C 2O 4)] −∞ spiral chains. The structure of the one-dimensional anionic chain exhibits V(IV) octahedra bridged by bisbidentate oxalate groups. Crystal data: 1·4H 2O, monoclinic P2 1/ n, A = 12.694(3), B = 12.531(3), C = 17.17(3) Å, β = 106.32(2)°, V = 2621.3(13) Å 3, Z = 2, Dcalc = 1.501 g cm −3, structure solution and refinement converged at a conventional residual of 0.0518; 2, tetragonal P4 3, A = 12.145(2), C = 15.991(3) Å, V = 2358.7(12) Å 3, Z = 4, R = 0.0452. 相似文献
14.
The metal ion complexing properties of the ligand HQC (8-hydroxyquinoline-2-carboxylic acid) are reported. The structures of [Zn(HQCH) 2] · 3H 2O (1) and [Cd(HQCH) 2] · 3H 2O (2) were determined (HQCH = HQC with phenol protonated). Both 1 and 2 are triclinic, space group , with Z = 2. For 1 a = 7.152(3), b = 9.227(4), c = 15.629(7) Å, = 103.978(7)°, β = 94.896(7)°, γ = 108.033(8)°, R = 0.0499. For 2 a = 7.0897(5), b = 9.1674(7), c = 16.0672(11) Å, = 105.0240(10)°, β = 93.9910(10)°, γ = 107.1270(10)°, R = 0.0330. In 1 the Zn has a distorted octahedral coordination geometry, with Zn–N of 2.00 and 2.15 Å, and Zn–O to the protonated phenolic oxygens of 2.431 and 2.220 Å. The structure of 2 is similar, with Cd–N bonds of 2.220 and 2.228 Å, with Cd–O bonds to the protonated phenolate oxygens of 2.334 and 2.463 Å. The structures of 1 and 2, and isomorphous Ni(II) and Co(II) HQC complexes reported in the literature, show very interesting short (<2.5 Å) O–O distances in H-bonds involving the protons on the coordinated phenolates and lattice water molecules. These are discussed in relation to the possible role of short low-energy H-bonds in alcohol dehydrogenase in mediating the transfer of the hydroxyl proton of the alcohol to an adjacent serine oxygen. The formation constants for HQC are determined by UV–Visible spectroscopy at 25 °C in 0.1 M NaClO4 with Mg(II), Ca(II), Sr(II), Ba(II), La(III), Gd(III), Zn(II), Cd(II), Ni(II), Cu(II), and Pb(II). These show greatest stabilization with metal ions with an ionic radius above 1.0 Å. This is as would be expected from the fact that HQC forms two five-membered chelate rings on complex-formation, which favors larger metal ions. The ligand design concept of using rigid aromatic backbones in ligands to achieve high levels of preorganization, and hence the high log K values (for a tridentate ligand) and strong metal ion selectivities observed for HQC, is discussed. 相似文献
15.
The chloro complexes trans-[Pt(Me)(Cl)(PPh 3) 2], after treatment with AgBF 4, react with 1-alkynes HC---C---R in the presence of NEt 3 to afford the corresponding acetylide derivatives trans-[Pt(Me) (C---C---R) (PPh 3) 2] (R = p-tolyl (1), Ph (2), C(CH 3) 3 (3)). These complexes, with the exception of the t-butylacetylide complex, react with the chloroalcohols HO(CH 2) nCl ( n = 2, 3) in the presence of 1 equiv. of HBF 4 to afford the alkyl(chloroalkoxy)carbene complexes trans-[Pt(Me) {C[O(CH 2) nCl](CH 2R) } (PPh 3) 2][BF 4] (R = p-tolyl, N = 2 (4), N = 3 (5); R=Ph, N = 2 (6)). A similar reaction of the bis(acetylide) complex trans-[Pt(C---C---Ph) 2(PMe 2Ph) 2] with 2 equiv. HBF 4 and 3-chloro-1-propanol affords trans-[Pt(C---CPh) {C(OCH 2CH 2CH 2Cl)(CH 2Ph) } (PMe 2Ph) 2][BF 4] (7). T alkyl(chloroalkoxy)-carbene complex trans-[Pt(Me) {C(OCH 2CH 2Cl)(CH 2Ph) } (PPh 3) 2][BF 4] (8) is formed by reaction of trans-[Pt(Me)(Cl)(PPh 3) 2], after treatment with AgBF 4 in HOCH 2CH 2Cl, with phenylacetylene in the presence of 1 equiv. of n-BuLi. The reaction of the dimer [Pt(Cl)(μ-Cl)(PMe 2Ph)] 2 with p-tolylacetylene and 3-chloro-1-propanol yields cis-[PtCl 2{C(OCH 2CH 2CH 2Cl)(CH 2C 6H 4- p-Me}(PMe 2Ph)] (9). The X-ray molecular structure of (8) has been determined. It crystallizes in the orthorhombic system, space group Pna2 1, with a = 11.785(2), B = 29.418(4), C = 15.409(3) Å, V = 4889(1) Å 3 and Z = 4. The carbene ligand is perpendicular to the Pt(II) coordination plane; the PtC(carbene) bond distance is 2.01(1) Å and the short C(carbene)-O bond distance of 1.30(1) Å suggests extensive electronic delocalization within the Pt---C(carbene)---O moietry. 相似文献
16.
The reactions of [(H 5C 6) 3P] 2ReH 6− with (CH 3CN) 3Cr(CO) 3, (diglyme)Mo(CO) 3 or (C 3H 7CN) 3W(CO) 3 led to the formation of [(H 5C 6) 3P] 2ReH 6M(CO) 3− (M = Cr, Mo, W) complexes. These have been characterized by IR and NMR spectroscopies, as well as elemental analyses. A single crystal X-ray diffraction study has also been carried out for the M = Cr complex as a K(18-crown-6) + salt. The complex crystallizes as a THF monosolvate in the monoclinic space group P2 1/ n with a = 22.323(6), B = 9.523(2), C = 27.502(5) Å, β = 104.98(2) 0 and V = 5648 Å 3 for Z = 4. The Re---Cr separation is 2.5745(12) Å, and the two phosphine ligands are oriented unsymmetrically. Although the hydride ligands were not found, the presence of three bridging hydrides and a dodecahedral coordination geometry about rhenium could be inferred. Low temperature 1H and 31P NMR spectroscopic studies did not reveal the low symmetry of the solid state structure. 相似文献
17.
Hexacoordination of the neutral phosphorus compounds 4–6 is evidenced by their high field 31P NMR chemical shifts and is further substantiated by the crystal structure of 5 and 6.5 contains the potentially bis-chelating ligand Ar = (C 6H 3(CH 2NMe 2) 2-2,6) and 6 the same ligand with a protonated amino group. In both cases the compounds exhibit slightly distorted octahedral geometry. In compound 5, only one NMe 2 group is coordinated to the phosphorus atom with an N → P bond of 2.063 Å. In compound 6, the NMe 2 group is coordinated to the phosphorus atom with an N → P bond of 2.007 Å while the dimethylammonium substituent is pointing away from the phosphorus atom forming a hydrogen bridge with two oxygen atoms. The fluxional behavior of these three novel six-coordinate phosphorus compounds was studied by dynamic 1H NMR spectroscopy. 相似文献
18.
Reaction of LaCl 3·7H 2O containing small amounts of La(NO 3) 3·7H 2O as an impurity with 12-crown-4 or 18-crown-6 in 3:1 CH 3CN:CH 3OH resulted in the isolation of the mixed anion complexes [LaCl 2(NO 3)(12-crown-4)] 2, [La(NO 3)(OH 2) 4(12-crown-4)]Cl 2·CH 3CN and [LaCl 2(NO 3)(18-crown-6)]. The nine-coordinate dimer, [LaCl 2(NO 3)(12-crown-4)] 2, has all of the anions in the inner coordination sphere and La 3+ has a capped square antiprismatic geometry. It crystallizes in the orthorhombic space group Pbca with (at −150 °C) a = 12.938(6), B = 15.704(3), C = 13.962(2) Å, and Dcalc = 2.08 g cm −3 for Z = 4. The second complex isolated from the same reaction, [La(NO 3)(OH 2) 4(12-crown-4)]Cl 2·CH 3CN, has the bidentate nitrate anion in the inner coordination sphere but the two chloride anions are in a hydrogen bonded outer sphere. This complex is ten-coordinate 4A,6B-expanded dodecahedral and crystallizes in the monoclinic space group P2 1 with (at 20 °C) A = 7.651(2), B = 11.704(7), C = 11.608(4) Å, β = 95.11(2)°, and Dcalc = 1.80 g cm −3 for Z = 2. The 18-crown-6 complex, [LaCl 2(NO 3)(18-crown-6)], has all inner sphere anions and has ten-coordinate 4A,6B-expanded dodecahedral La 3+ centers. It crystallizes in the orthorhombic space group Pbca with (at 20 °C) a = 14.122(7), B = 13.563(5), C = 19.311(9) Å, and Dcalc = 1.89 g cm −3 for Z = 8. 相似文献
19.
Two novel complexes Co(N 3) 2(PNN) 4 (I) and Mn(N 3) 2(PNN) 2(CH 3OH)(C 2H 5OH) (II) (PNN=2-( p-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3–oxide) were synthesized and characterized by infrared spectra, elemental analyses and UV–Vis techniques. The crystal structures of both complexes have been determined by X-ray diffraction analysis. Complex I is a neutral five-spin system and adopts a centrosymmetric tetragonally compressed octahedral coordination geometry in which Co(II) ion is coordinated to four radicals through the nitrogen atoms of the pyridine rings and two azide anions occupying the axial positions. Complex II is a neutral three-spin system in which Mn(II) ion is bound to two azide anions, two alcohol molecules and two radicals through the nitrogen atom of pyridine rings, and shows one-dimensional chain structure via hydrogen bonds ( dON=2.78 Å). The magnetic properties for complexes I and II have been investigated in the temperature range 2–300 K. A theoretical model has been developed for complex I and the magnetic behaviors for both complexes have been discussed in detail. 相似文献
20.
The coordination chemistry of the new bidentate nitrogen ligands 8-(2-pyridyl)quinoline (8-PQ) and 8-(6-methyl-2-pyridyl)quinoline (Me-8-PQ) towards palladium and platinum has been studied. Several (NN)Pd(R)Cl and (NN)Pd(alkene) complexes have been synthesized. The complex (8-PQ)Pd(Me)Cl has been characterised by a single crystal X-ray determination (crystal data triclinic space group ). A fast CO insertion occurs into the palladium-carbon bond of the complexes (NN)Pd(Me)Cl providing the (NN)Pd(C(O)Me)Cl complexes. For (8-PQ)Pd(C(O)Me)Cl an X-ray structure determination has been carried out (crystal data: monoclinic space group P2 1/ c with a=9.084(4), B=10.179(3), C=16.400(3) Å, β=95.59(2)°, V=1509.2(9) Å 3, R=0.043, Z=4). Unexpected in both molecular structures is the large dihedral angle between the plane of the bidentate nitrogen ligand and the coordination plane of the palladium. Both bidentate coordinating ligands 8-PQ and Me-8-PQ show a relatively large bite angle. A monodentate coordination mode has been observed for the complexes (NN)M(PEt 3)Cl 2 (M=Pd, Pt), as the pyridyl group of the ligand is coordinated to the metal while the quinoline group is dissociated from the metal, which is shown in the X-ray structure determination for the complex (8-PQ)Pd(PEt 3)Cl 2 (crystal data: monoclinic space group P2 1/ a with A=15.736(2), B=7.782(1), C=18.255(3) Å, β=102.98(1)°, V=2178.3(6) Å 3, R=0.062, Z=4). 相似文献
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