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1.
Palladium–bis(oxazoline) complexes (Pd-BOX-A and Pd-BOX-B) were synthesized and characterized by 1H, 13C NMR, IR and elemental analysis. The molecular structures of the complexes were confirmed by single-crystal X-ray analysis. In both cases, the palladium center is coordinated by the nitrogen atoms of the two oxazoline rings and two chloride ligands in a distorted square planar geometry. Despite the fact that the bis(oxazoline) ligand is achiral, the asymmetrical substitution on the phenyl spacer and the rigid backbone of the complex Pd-BOX-A induce inherent chirality and the compound crystallizes as a racemic mixture. Both complexes were found to be highly effective catalysts for Suzuki–Miyaura, Mizoroki–Heck and Sonogashira cross-coupling reactions. They also show excellent catalytic activities toward carbonylative coupling reactions.  相似文献   

2.
A nickel(Ⅱ) complex containing both dithiolato and phosphine ligands, Ni_2(PPh_3)_2(edt)_2(edt = SCH_2CH_2S~(2-)), has been prepared and characterized by X-ray diffration. The complex crystallizesin the triclinic system, space group P-1, with a = 10.693(3), b = 17.457 (6), c = 10.606 (3)A, α=102.84(2), β = 96.49 (2), γ = 82.56(3)°; V = 1906.8 A~3; D_c = 1.439g.cm~(-3) for Z=2; the final con-ventional R was 0.052 based on 3338 observed reflections. Nickel atoms are linked by two sulfuratoms from two edt ligands with the Ni--Ni distance of 2.893 A, and each Ni atom is coordinatedby one phosphorus atom and three sulfur atoms with a square-planar geometry, where the average:length of Ni--S bond is 2.180 A and Ni--P bond 2.188 A. The UV-Vis and ~1H NMR spectra havealso been recorded.  相似文献   

3.
The two complexes [Ni(oxen)Cu(L)2](ClO4)2.xH2O (L=2,2'-bipyridyl(bpy), 1,10-phenanthroline(phen)) have been synthesized, where oxen is N,N'-bis(2-aminoethyl)oxamido di-anion. The crystal structure of [Ni(oxen)Cu(bpy)2](ClO4)2.CH3OH has been determined by X-ray diffraction method. The crystal is triclinic system, space group P1 with a=12.179(1),b=12.298(2), c=11.476(2) A, a=97.57(1), B=97.52(1), 7=80.29(2), V=1669.04(67) A3, Z=2, Dcalcd=1.667 g/cm3. The structure has been refined to final R of 0.076 and Rw of 0.080, respectively. The complexes have an extended oxamido-bridged structure and consist of Ni(Ⅱ) ion in a square planar environment and Cu(Ⅱ) ion in a distorted octahedral environment.  相似文献   

4.
Starting from cis-[Ru(dcbpyH2)2Cl2] (1), two new heteroleptic ruthenium(II) complexes, [Ru(dcbpyH2)2(L1)](NO3)2 (L1?=?2-(2′-pyridyl)quinoxaline (2), and [Ru(dcbpyH2)2(L2)](NO3)2 (L2?=?4-carboxy-2-(2′-pyridyl)quinoline (4); dcbpyH2?=?2,2′-bipyridine-4,4′-dicarboxylic acid), were synthesized and spectroscopically characterized. During the preparation of 2 and 4, the homoleptic [Ru(dcbpyH2)3]Cl2 complex (3) was isolated as a side product. Characterization includes IR and Raman spectroscopy, UV-Vis, multinuclear NMR spectroscopy, elemental, and ESI-mass spectrometric analyses.  相似文献   

5.
Wu  Hui-lu  Gao  Yi-ci  Yu  Kai-bei 《Transition Metal Chemistry》2004,29(2):175-179
Four 5-coordinate zinc complexes containing the tripod ligand, tris(2-benzimidazolylmethyl)amine (ntb), and four different ,-unsaturated carboxylates (L1–4), with compositions [Zn(ntb)(L1–4)](NO3nH2O (L1 = acrylate; L2 = -methacrylate; L3 = trans-cinnamate; L4 = 2-hydroxycinnamate; n = 1, 1.5 and 2), were synthesized and characterized by means of elemental analyses, electrical conductivities, thermal analyses, i.r., u.v., and 1H-n.m.r. spectra. The novel crystal structure of [Zn(ntb)(L3)](NO3)·H2O·DMF has been determined by a single-crystal X-ray diffraction method, and shows that each zinc ion is linked to a tris(2-benzimidazolymethyl)amine (ntb) unit and a trans-cinnamate. The zinc ion is 5-coordinate with a N4O ligand set. The coordination geometries of the zinc ion may be best described as a distorted trigonal bipyramid of site symmetry C3.  相似文献   

6.
Two new ternary complexes of manganese(II) with tris(2-benzimidazylmethyl)amine (ntb), and two different α,β-unsaturated carboxylates, {[Mn(ntb)(acrylate)](ClO4)}2?·?(H2O)·3(CH3OH) (1) and {[Mn(ntb)(α-methacrylate)](ClO4)}2·(H2O)·2(CH3OH) (2), have been synthesized and characterized by means of elemental analyses, thermal analyses, IR, UV and single crystal X-ray diffraction. In the two complexes, ntb functions as a tripodal tetradentate ligand, resulting in trigonal pyramidal geometry. In each complex, an additional ligand, acrylate anion, or α-methacrylate anion, is coordinated at the opened site trans to the apical nitrogen atom of the ntb ligand. The crystal structure of 1 shows two crystallographically independent but chemically identical [Mn(ntb)(acrylate)]+ cations. In 2, the crystal structure shows two crystallographically independent and chemically different [Mn(ntb)(a-methacrylate)]+ cations. Cyclic voltammograms of the manganese complexes indicate a quasireversible Mn3+/Mn2+ couple. The X-band EPR spectrum of the complexes exhibits a six-line manganese hyperfine pattern with g?=?2, A?=?97 (1) and 93?G (2). The spectrum confirms that the material is high-spin Mn(II).  相似文献   

7.
Monometallic zinc(II) and nickel(II) complexes, [Zn(H2nsh)(H2O)] (1) and [Ni(H2nsh)(H2O)2] (2), have been synthesized in methanol by template method from bis(2-hydroxy-1-naphthaldehyde)succinoyldihydrazone (H4nsh). Reaction of monometallic complexes with alternate metal(II) acetates as a transmetallator in 1 : 3 molar ratio resulted in the formation of heterobimetallic complexes [NiZn(nsh)(A)3] and [ZnNi(nsh)(A′)2] (A = H2O (3), py (4), 2-pic (5), 3-pic (6), 4-pic (7)), (A′ = H2O (8), py (9), 2-pic (10), 3-pic (11), and 4-pic (12)). The complexes have been characterized by elemental analyzes, mass spectra, molar conductance, magnetic moments, electronic, EPR, and IR spectroscopies. All of the complexes are non-electrolytes. Monometallic zinc(II) is diamagnetic while monometallic nickel(II) complex and all heterobimetallic complexes are paramagnetic. The metal centers in heterobimetallic complexes are tethered by dihydrazone and naphthoxo bridging. Zinc(II) is square pyramidal; nickel(II) is six-coordinate distorted octahedral except [ZnNi(nsh)(A)2], in which nickel(II) has square-pyramidal geometry. The displacement of metal center in monometallic complexes by metal ion has been observed in the resulting heterobimetallic complexes.  相似文献   

8.
Mercury(II) complexes of pyrrolidinedithiocarbamate (PDTC) having the general formula [Hg(PDTC)X] (X = Cl?, SCN?, and CN?) and [Hg(PDTC)2] have been prepared and characterized by elemental analysis, IR, and NMR. The crystal structure of [Hg(PDTC)2] has also been determined by X-ray crystallography, showing that the complex is a centrosymmetric dimer, [Hg2(PDTC)4] (bis[µ2-(pyrrolidinedithiocarbamato-S,S′)(pyrrolidinedithiocarbamato-S,S′)mercury(II)]) (1). The solid-state structure of 1 contains two crystallographically equivalent Hg(II) centers in a distorted tetrahedron.  相似文献   

9.
《Journal of Coordination Chemistry》2012,65(16-18):2487-2509
Abstract

Reaction of 2-amino-5-halopyridine molecules with Cu(II) halides in the solid state via mechanochemical techniques produced four coordination complexes, (5BAP)2CuBr2 (2a), (5BAP)2CuCl2 (3), (5CAP)2CuCl2 (4), (5CAP)2CuBr2 (5) [5BAP?=?2-amino-5-bromopyridine; 5CAP?=?2-amino-5-chloropyridine]. In all compounds, the 5BAP or 5CAP ligands are coordinated to the Cu(II) ion through the pyridine N atom along with two halide ions. Compounds 2 and 3 crystallized in the P-1 and P21/c space groups, respectively. Temperature dependent magnetic susceptibility data for 2 were fit to the antiferromagnetic rectangle model (J?=?–4.5(2) K; α?=?0.89(17)), while the data for 3 were fit to the uniform chain model (J?=?–4.20(6) K), indicating a significant difference in the interchain interactions. Both 4 and 5 crystallize with the 5CAP ligands in the syn-conformation in the space groups I2/a and P21/n, respectively. Compound 4 formed the expected dimeric structure via bridging chloride ions and the magnetic data were successfully fit to the dimer model (J?=?–2.57(5) K), while 5 unexpectedly formed a structural chain via Br…Br contacts which exhibits very weak antiferromagnetic interactions. An intermediate structure, (5BAP)(H2O)CuBr2 (1), was prepared and characterized via mechanochemical methods along with an isomer of (5BAP)2CuBr2 (2b).  相似文献   

10.
Reactions of anhydrous CoX2 (X?=?Br?, SCN?) and Ni(ClO4)2 with N,N,N′,N′-tetraisobutylpyridine-2,6-dithiocarboxamides (S-dbpt), N,N,N′,N′-tetraisopropyl pyridine-2,6-dithiocarboxamides (S-dppt), and N,N,N′,N′-tetraethylpyridine-2,6-dithiocarboxamides (S-dept) lead to the formation of [Co(S-dbpt)Br2] (1), [Co(S-dppt)(SCN)2] (2), and [Ni(S-dept)2]·(ClO4)2·H2O (3), respectively. The X-ray crystal structures of the three S-dapt ligands and three complexes along with spectroscopic analyzes are presented. The molecular structure investigations of the S-dapt ligands show that the thiamide planes are twisted with respect to the pyridine ring, which is more in the case of phenyl groups. The structures of the Co(II) complexes reveal that an increase in steric crowding on the amide side arms of the ligands has no substantial effect on the geometry adopted by the corresponding complexes. The Co(II) gives only 1?:?1 five-coordinate, ion-paired complexes with a distorted square pyramidal geometry. Ni(II), on the other hand, prefers an octahedral geometry with 1?:?2 metal–ligand ratio. The coordination behavior of S-dapt has been compared to the analogous oxo(O-daap) ligands. Lesser propensity of S atom to get involved in H-bonding interactions ensures an S-N-S type of tridentate coordination by S-dapt.  相似文献   

11.
Two heterometallic coordination complexes, {[Cu(aeop)Zn(H2O)3]2?·?3H2O} n (1) and [Cu(aeop)Ni(H2O)4]?·?4H2O (2) (H4aeop?=?N-(2-aminoterephthalic acid)-N′-(1,3-propanediamine)oxamidate), have been synthesized and characterized by elemental analyses, IR, UV spectroscopy, thermogravimetric analysis, and X-ray crystal diffraction. Complex 1 features a 1-D chain constructed from neutral tetranuclear units. Complex 2 is a neutral binuclear complex. Through intermolecular hydrogen-bonding interactions, 2 gives a 3-D network structure. The variable temperature magnetic susceptibility measurements (2–300?K) of 2 show a pronounced antiferromagnetic interaction between the copper(II) and nickel(II), and the exchange integral J is equal to ?42.7?cm?1.  相似文献   

12.
13.
The current article describes the synthesis and characterization of the following adducts: [Cd(2-mpipdtc)2(1,10-phen)], [Cd(2-mpipdtc)2(bipy)], [Cd(4-mpipdtc)2(1,10-phen)], [Cd(4-mpipdtc)2(bipy)] (where 2-mpipdtc? = 2-methylpiperidinecarbodithioate anion, 4-mpipdtc? = 4-methylpiperidinecarbodithioate anion, 1,10-phen = 1,10-phenanthroline and bipy = 2,2′-bipyridine). A single crystal X-ray structural analysis was carried out for [Cd(4-mpipdtc)2(1,10-phen)]. IR spectra of the complexes show the contribution of the thioureide form to the structures. Reduction in νC–N(thioureide) for the mixed ligand complexes is attributed to the change in coordination number from four to six and the steric effect exerted by 1,10-phenanthroline or 2,2′-bipyridine. Deshielding of the protons adjacent to nitrogen in the 1H NMR spectra is attributed to drift of electrons from the nitrogen of NR2, forcing electron density towards sulfur via the thioureide π-system. Single crystal X-ray structural analysis of [Cd(4-mpipdtc)2(1,10-phen)] showed that the cadmium is in a distorted octahedral environment with a CdS4N2 chromophore. The presence of 1,10-phenanthroline in the coordination sphere of Cd(dtc)2 increases the Cd–S distances and decreases the S–Cd–S angles. VBS analysis supports the determined structure.  相似文献   

14.
Two crystal modifications of a novel complex bis(μ2-chloro)tetrachlorodicuprate(II) bis[(18-crown-6)potassium, [K{(18-crown-6)}2Cu2Cl6] were synthesized and studied by X-ray diffraction. The structures of two monoclinic modifications—Iα (space group P21/n, a = 9.053, b = 33.815, c = 13.469 Å, β = 101.29°, Z = 4) and Iβ (space group P21/c, a = 10.991, b = 8.187, c = 22.542 Å, β = 98.15°, Z = 2) were solved by the direct method and refined by the full-matrix least-squares method in anisotropic approximation to R = 0.073 (Iα) and 0.068 (Iβ) for 4883 (Iα) and 3525 (Iβ) independent reflections (CAD-4 automated diffractometer, λMoK α). The molecules of Iα and Iβ consist of the central binuclear complex anion [Cu2Cl6]2? and two peripheral host-guest cationic fragments [K(18-crown-6)]+, each linked with the [Cu2Cl6]2? anions through the K-Cl bonds. The molecule of Iα and centrosymmetric Iβ molecule have different structures, since they have different orientation of the [K(18-crown-6)]+ fragments relative to the central [Cu2Cl6]2? anion. The coordination polyhedron of the Cu2+ cation in the latter anion in Iα and Iβ is intermediate between flattened tetrahedron and square. In the [K(18-crown-6)]+ ions of Iα and Iβ, the K+ cation has the distorted hexagonal pyramidal coordination polyhedron with six O atoms of the 18-crown-6 ligand in a base and bifurcate vertex at two Cl atoms of the [Cu2Cl6]2? anion. The 18-crown-6 ligands of Iα and Iβ have standard crown conformation.  相似文献   

15.
In this review are classified and analyzed structural parameters of almost 90 monomeric organoplatinum complexes with inner coordination spheres consisting of PtPCOX (X?=?N, Cl, S), PtPCNX (X?=?Cl, S, Br, I, As) and PtPCClX (X?=?S, I, As). These complexes crystallized in three crystal systems: orthorhombic (× 11), triclinic (× 32) and monoclinic (× 45). Distorted square planar arrangements about the Pt(II) atoms are provided by mono-, heterobi- and heterotridentate donor ligands. The chelating ligands create a wide variety of four-, five- and six-membered metallocyclic rings and the effects of both steric and electronic factors influence the L–Pt–L bite angles. There are wide variations in the trans-positions of the donor ligands. Two examples are classified as distortion isomers.  相似文献   

16.
Reaction of [Pt(bipy)Cl2] (bipy = 2,2′-bipyridine) with an excess of silver triflate in refluxing acetonitrile readily affords [Pt(bipy)(MeCN)2](CF3SO3)2 as a yellow, crystalline solid. A single crystal X-ray diffraction study shows that the cations are arranged in a zig-zag manner in rows parallel to the b axis of the monoclinic unit cell. Consideration of the crystal structures of related bipyridyl ligand complexes of platinum(II), leads to the conclusion that a stacked structure with intermolecular Pt…Pt interactions for the title compound is prevented by the electrostatic repulsion between adjacent cations that are doubly charged.  相似文献   

17.
Mercury(II) complexes, {[Hg(Ph2phen)(μ-Br)]2Br2} · CH3CN (1) and {[Hg(dmbpy)(µ-Br)]2Br2}(2) (where Ph2phen is 4,7-diphenyl-1,10-phenanthroline and dmbpy is 5,5′-dimethyl-2,2′-bipyridine), were synthesized from reaction of HgBr2 with Ph2phen and dmbpy in CH3CN and CH3OH. Both complexes were thoroughly characterized by elemental analysis, infrared, 1H and 13C NMR spectroscopy and single-crystal X-ray diffraction. Complexes 1 and 2 crystallize in the space group P21/n of the monoclinic and P 1 of the triclinic systems and contain four and one molecules per unit cell, respectively. The unit cell dimensions for 1 are: a = 20.422(4) Å, b = 11.384(2) Å, c = 20.665(4) Å, and β = 109.94(3)° and for 2 are: a = 8.7470(17) Å, b = 8.8328(18) Å, c = 9.4950(19) Å and α = 75.47(3)°, β = 82.21(3)°, γ = 85.56(3)°. According to X-ray structure determination both complexes are five coordinate with three bromides and one bidentate ligand; one bromide is set at a semi-bridging position.  相似文献   

18.
《Polyhedron》1999,18(8-9):1323-1328
The coordination mode of the title ligand, MPyPzCA (synthesised for the first time and characterised by elemental analyses, mass, IR and PMR spectral parameters), is reported by solid state isolation and physicochemical identification of copper(II) complexes, Cu(MPyPzCA)2X2.H2O (X=Cl/Br/NO3/ClO4). Magnetic and electronic spectral features classify the reported complexes as six coordinate distorted octahedral ones. IR spectra (4000–200 cm−1) of MPyPzCA and its complexes indicate different denticity of the two ligand moities namely neutral bidentate function through pyrazolyl 2N and pyridyl 1′N of one ligand (A) and the neutral tridentate behaviour through pyrazolyl 2N, pyridyl 1′N and the amidic oxygen of the second ligand system (B). The sixth apical coordination site is occupied by a water molecule in the perchlorate complex (as evident by X-ray data) or by the counter ion, X (X=Cl/Br/NO3). The electrochemical studies demonstrate easy oxidative nature of Cu(II) in the reported species. X-ray crystallographic studies of the perchlorate complex, [Cu(MPyPzCA)2(H2O)](ClO4)2, (Pna21, orthorhombic), has substantiated the conjecture that the geometry is distorted octahedral. The Cu-N (pyrazolyl) and Cu-N (pyridyl) bond lengths are 2.001(3) and 1.969(3) Å and 2.020(4) and 2.206(4) Å in the ligand systems, A and B. respectively; Cu-O (amidic oxygen) for ligand system B and Cu-O (water) bond lengths are 2.783(3) and 2.010(3) Å, respectively. The crystal structure is highly stabilised through extensive hydrogen bonding.  相似文献   

19.
The tridentate monoanionic ligand o,o′-(Me2NCH2)2C6H3 (NCN′) has been used to synthesize novel aryl-palladium(II) and -platinum(II) complexes [PtR(NCN′)] and [MX(NCN′)] (M = Pt, Pd). Three synthetic procedures are described, namely: (i) reaction of the cationic complex [M(NCN′)(H2O)]+ with KX or NaX to give [MX(NCN′)] (X = Cl, I, O2CH, NCS, NO2, NO3); (ii) displacement reactions using AgX with [MBr(NCN′)] to give [MX(NCN′)] (X = CN, O3SCF3. O2CMe, O2CCF3) and (iii) transmetallation reactions of [PtBr{C6H3(CH2NMe2)2-o,o′}] with organolithium to give [PtR{C6H3(CH2NMe2)2-o,o′}] (R = Ph, o-, m-, p-tolyl, CCPh, CC-p-tolyl). All complexes have been characterized by elemental analysis, and IR, 1H and 13C NMR spectroscopy.An X-ray diffraction study has shown that [PtBr{C6H3(CH2NMe2)2-o,o′}] (2) has a square-planar structure, in which the tridentate ligand is bonded via C(ipso) (PtC 1.90(1) Å), and two mutually trans-N donor atoms (PtN(1) 2.07(1), PtN(2) 2.09(1) Å). The fourth site trans to C(ipso) is occupied by bromine (PtBr 2.526(2) Å). The two chelate rings (NPtC(ipso) 82.9(5) and 81.5(5)°) are distinctly puckered, with the two NMe2 groups on opposite sides of the aryl plane. The PtC bond in 2 is shorter than analogous bonds in other arylplatinum(II) complexes, as a result of (i) the rigid structure of the tridentate ligand and (ii) the presence of two hard N donor atoms trans to one another across the platinum centre.  相似文献   

20.
Abstract

Reaction of α-keto stabilized sulfur ylide (Me)2SCHC(O)C6H4-p-CN (Y) with HgX2 (X?=?Cl, Br, and I) led to the formation of new dinuclear products of the type [HgX2(Y)]2 (X?=?Cl (1), Br (2), and I (3)). Furthermore, the reaction of the corresponding sulfur ylide (Y) with Hg(NO3)2·H2O in equimolar ratio, using methanol as a solvent, was shown to produce the polynuclear complex [(Y)Hg(NO3)2]n (4). The obtained compounds were characterized using elemental analysis, IR, 1H and 13C NMR techniques. The structures of compounds Y and 1 were characterized by single-crystal X-ray diffraction (XRD) analysis. Also, in order to confirm the crystalline nature of complexes 13, powder XRD pattern was used. Likewise, the antioxidant property of the complexes was examined by 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging which revealed the strong-to-moderate radical scavenging ability (IC50; 0.163?±?0.004 to 0.936?±?0.012?mg·mL?1) of the synthesized compounds. Further, results from this study indicated that the compounds possess moderate antibacterial activity.  相似文献   

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