Organotransition-Metal Complexes of Multidentates 1. Synthesis and Characterization of N,N-Bis(Pyrazol-1-Ylmethyl)Aminomethane and N,N-Bis(3, 5-Dimethylpyrazol-1-Ylmethyl)-Aminomethane Derivatives of the Group VI Metal Carbonyls

N, N-bis(pyrazol-1-ylmethyl)aminomethane (bpam) and N, N-bis(3, 5-dimethylpyrazol-1-ylmethyl)aminomethane (bdmpam) reacted with M(CO)₆ or M(CO)₃(CH₃CN)₃ in acetonitrile to give respectively fac-(bpam)M(CO)₃ and fac-(bdmpam)M(CO)₃ in good yields (M=Cr, Mo, W). These complexes are characterized by elemental analysis, IR, and NMR and compared with the related polypyrazolylborate complexes of the group VI metal carbonyls.     

Organotransition-Metal Complexes of Multidentates 2. Synthesis and Allyl Bromination of N,N-Bis(3,5-Dimethylpyrazol-1-YL)Methane Derivatives of the Group VI Metal Carbonyls

N,N-Bis(3,5-dimethylpyrazol-1-yl)methane (H₂CPz'₂) reacts with the hexacarbonyls of chromium, molybdenum, and tungsten to give cis-(H₂CPz'₂)M(CO)₄ derivatives with M=Cr, Mo, W. The direct allyl bromination of these complexes is also investigated and only the molybdenum complex is converted into (H₂CPz'₂)Mo(CO)₂(π-C₃H₃)(Br).     

二(2-苯并咪唑亚甲基)胺配合物的合成、晶体结构、活性和量子 化学研究

合成了[二(2-苯并咪唑亚甲基)胺][咪唑]合Cu(Ⅱ)Zn(Ⅱ)Cu(Ⅱ)高氯酸盐配合物C_(57)H_(57)N_(21)Cu_2Zn(ClO_4)_6·6[(CH_3)_2NCHO],并进行了元素分析、红外和紫外表征,用X射线衍射的方法测定了晶体结构,进行了生物活性测试和量子化学计算     

Synthesis, X-ray structure and properties of a new nitrite-bound copper(II) complex with 2-(3,5- dimethylpyrazol-1-ylmethyl)pyridine in a CuN4(O) coordination

Synthesis and characterization of a nitrite-bound copper(II) compound [CuL⁴)₂(ONO)]ClO₄ have been achieved (L⁴ = 2-(3,5-dimethylpyrazol-1-ylmethyl)pyridine]. The bidentate ligand L⁴ provides a pyridine and a pyrazole donor site; however, they are separated by a methylene spacer. The complex has been structurally characterized and it belongs to only a handful of complexes having nitrito-bound mononuclear copper(II) centre. The metal atom has a distorted square pyramidal geometry with the copper atom displaced from the equatorial plane by 0.25 Å. In MeCN solution the green complex exhibits a broad ligand-field transition at 655 nm with a shoulder at 675 nm and in dichloromethane-toluene glass (80 K) it exhibits an EPR spectral feature characteristic of the unpaired electron in the d_x²−y² orbital. Variable-temperature (80–300 K) magnetic susceptibility measurements in the solid state as well as room temperature measurement in MeCN solution reveal mononuclear magnetically dilute copper(II) centre. When examined by cyclic voltammetry (MeCN solution) it displays electrochemically irreversible Cu^II---Cu^I response [cathodic peak potential, E_pc (V vs saturated calomel electrode (SCE)): −0.32]. An oxidative response is observed at 1.14 V, probably due to bound-nitrite oxidation and is partially removed to generate a solvated complex at the electrode surface. The latter species gives rise to reversible Cu^II---Cu^I redox response [ ].     

Synthesis,structure, electrochemical properties,and antioxidant activities of copper(II) and zinc(II) complexes with N,N-bis(N-ethyl-2-ylmethylbenzimidazol)allylamine ligand

N,N-bis(N-methyl-2-ylmethylbenzimidazole)aniline (EtAIDB) and its transition metal complexes, [Cu(EtAIDB)Br₂]·EtOH {dibromo[N,N-bis(N-methyl-2-ylmethylbenzimidazole)aniline] copper(II) ethanol} (1) and [Zn(EtAIDB)Br₂] {dibromo[N,N-bis(N-methyl-2-ylmethylbenzimidazole)aniline] zinc(II)} (2), have been synthesized and characterized by elemental analysis, molar conductivity, UV–visible, and IR spectroscopy. The X-ray crystallographic studies of 1 and 2 have shown two different arrangements: 1 is distorted square-based pyramidal, while 2 can be treated as distorted tetrahedral. The cyclic voltammogram of 1 represents quasi-reversible Cu²⁺/Cu⁺ pairs. In vitro antioxidant tests showed that 1 had significant antioxidant activity against superoxide and hydroxy radicals.     

Crystal structures of cobalt(II) complexes with N-(2-hydroxyethyl)iminodiacetic and N,N-bis(2-carbamoylethyl)aminoacetic acids: Co(Heida)·2H2O and Co(Bcegly)(ClO4)·2H2O

The cobalt atom in the structures studied is situated in the center of an octahedron involving donor atoms N and 3O organic ligands Heida or Bcegly (ions of hydroxyethyliminodiacetate or bis(carbamoylethyl)aminoacetate, respectively), water molecule oxygen atom, and a carboxylic atom of the neighboring ligand in the trans-position to the N atom, so that each (II) ion is linked with two organic anions. This results in a formation of infinite chains — uncharged [Co(Heida)(H₂O)]_n or cationic {[Co(Bcegly)(H₂O)]⁺}_n. In both cases, a molecule of crystallization water is present, and in the second case, the charge of the chains is compensated by perchlorate ions. Aminoacetic cycle of the Heida ligand is approximately coplanar to another such cycle, while a similar cycle of the Bcegly ligand is in the plane of one of six-membered aminopropionamide cycles.     

Synthesis, Characterization and Luminescence of Lanthanide Chloride Complexes with N,N,N'''',N''''-Tetra[(2-benzimidazolyl) methyl]-1,2-Ethanediamine

Imidazole groups play an important role in the coordination chemistry of the metal ions in many biological systems1. Earlier work has established its suitability for formations of binuclear copper1, iron2 and manganese3 complexes. Reaction of EDTB with Cu(H2O)6(BF4)2 in absolute ethanol has given a six-coordinate complex of [Cu(EDTB)](BF4)(BF3?O(C2H5)2)H2O4. Rare earth ions have similar physical and chemical properties with Ca2+ and Mg2+ which are important in biological systems. Wan…     

Synthesis and in vitro cytotoxicity of platinum(II) complexes with chiral N-monosubstituted 1,2-cyclohexyldiamine derivatives as the carrier groups

Eight platinum(II) complexes with the new chiral ligands, (1R,2R)-N ¹-(pyridine-2-ylmethyl) cyclohexane-1,2-diamine (R) or (1S,2S)-N ¹-(pyridine-2-ylmethyl) cyclohexane-1,2-diamine (S) as the carrier groups were designed, synthesized, and spectrally characterized. All platinum(II) complexes showed much better aqueous solubility than cisplatin and oxaliplatin. In vitro cytotoxicity of the compounds against human HepG-2, MCF-7, A549, and HCT-116 cell lines was evaluated. Results indicate that all compounds with R as the carrier group showed cytotoxicity against HCT-116, A549, and MCF-7 cell lines; however, all compounds with S as carrier group exhibited disappointing cytotoxicity against tested cell lines. Compound R2, bearing ClCH₂COO^- as leaving group, exhibited better cytotoxicity than that of carboplatin against A549 and MCF-7 cell lines and also showed close activity to oxaliplatin against HCT-116 cell line.     

Polar bonds in π-complexes. Preparation and crystal structures of cyclopentadienylcarbonyl iron(II) and ruthenium(II) benzoates andp-fluorobenzoates

Complexes of Fe(II) and Ru(II) of the general formula Cp(OC)₂MOC(O)C₆H₄X-p, where M=Fe, X=H, F (1, 2) or M=Ru, X=H, F (3, 4) have been prepared by reactingp-XC₆H₄COOAg with [CpFe(CO)₂]₂ or CpRu(CO)₂I. The crystal structures of complexes1–3 have been determined using X-ray diffraction. Compounds1 and3 are isomorphous. The COO group in1–3 is coordinated as a monodentate ligand. As the latter and the CO ligands are electronically non-equivalent, the coordination of the Cp ligand to the metal is slightly asymmetric.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 395–399, February, 1993.     

Synthesis and Characterization of Copper(II) and Zinc(II) Tricyanomethanide (tcm) Complexes with Di(2‐pyridyl)amine (dpyam) as Co‐ligands: [Cu(dpyam)(tcm)2], [Cu(dpyam)(tcm)(OAc)] and Zn(dpyam)2(tcm)2

Three new transition metal tricyanomethanide complexes [Cu(dpyam)(tcm)₂] ( 1 ), [Cu(dpyam)(tcm)(OAc)] ( 2 ) and Zn(dpyam)₂(tcm)₂ ( 3 ) were synthesized and characterized by single crystal X‐ray diffraction analysis. In 1 each copper(II) atom is coordinated to three tcm anions and one dpyam molecule to form a square pyramide geometry. In 2 the coordination geometry around the central metal is also square pyramidal, and each copper atom is surrounded by two tcm anions, one dpyam ligand and one OAc. Both 1 and 2 display a µ_1,5‐tcm bridged infinite chain structure. In 3 each zinc(II) atom is coordinated by two tcm anions and two dpyam molecules to form a distorted octahedral geometry. Different from the former two complexes, 3 shows a mononuclear structure. Magnetic susceptibility measurement in the range 2–300 K indicates that there are weak antiferromagnetic couplings between adjacent copper(II) ions in 1 (J=?0.03 cm^?1) and 2 (J=?0.11 cm^?1) respectively.     

Counter‐anion role in the formation of two supramolecular complexes: [Ag2(DPP)2](ClO4)2·CH3CN and [Ag2(DPP)2(NO3)2] {DPP is N‐[(diphenylphosphanyl)methyl]pyridin‐4‐amine}

The title compounds, bis{μ‐N‐[(diphenylphosphanyl)methyl]pyridin‐4‐amine‐κ²N¹:P}disilver bis(perchlorate) acetonitrile monosolvate, [Ag₂(C₁₈H₁₇N₂P)₂](ClO₄)₂·CH₃CN, (1), and bis{μ‐N‐[(diphenylphosphanyl)methyl]pyridin‐4‐amine‐κ²N¹:P}bis[(nitrato‐κ²O,O)silver], [Ag₂(C₁₈H₁₇N₂P)₂(NO₃)₂], (2), each contain disilver macrocyclic [Ag₂(C₁₈H₁₇N₂P)₂]²⁺ cations lying about inversion centres. The cations are constructed by two N‐[(diphenylphosphanyl)methyl]pyridin‐4‐amine (DPP) ligands linking two Ag⁺ cations in a head‐to‐tail fashion. In (1), the unique Ag⁺ cation has a near‐linear coordination geometry consisting of one pyridine N atom and one P atom from two different DPP ligands. Two ClO₄⁻ anions doubly bridge two metallomacrocycles through Ag...O and N—H...O weak interactions to form a chain extending in the c direction. The half‐occupancy acetonitrile molecule lies with its methyl C atom on a twofold axis and makes a weak N...Ag contact. In (2), there are two independent [Ag(C₁₈H₁₇N₂P)]⁺ cations. The nitrate anions weakly chelate to each Ag⁺ cation, leading to each Ag⁺ cation having a distorted tetrahedral coordination geometry consisting of one pyridine N atom and one P atom from two different DPP ligands, and two chelating nitrate O atoms. Each dinuclear [Ag₂(C₁₈H₁₇N₂P)₂(NO₃)₂] molecule acts as a four‐node to bridge four adjacent equivalent molecules through N—H...O interactions, forming a two‐dimensional sheet parallel to the bc plane. Each sheet contains dinuclear molecules involving just Ag1 or Ag2 and these two types of sheet are stacked in an alternating fashion. The sheets containing Ag1 all lie near x = , , etc, while those containing Ag2 all lie near x = 0, 1, 2 etc. Thus, the two independent sheets are arranged in an alternating sequence at x = 0, , 1, etc. These two different supramolecular structures result from the different geometric conformations of the templating anions which direct the self‐assembly of the cations and anions.     

Two zinc(II) coordination complexes based on an asymmetric multidentate ligand: syntheses,structures, selective fluorescence sensing of iron(III) ions and thermal analyses

The rational selection of ligands is vitally important in the construction of coordination complexes. Two novel Zn^II complexes, namely bis(acetato‐κO)bis[1‐(1H‐benzotriazol‐1‐ylmethyl)‐2‐propyl‐1H‐imidazole‐κN³]zinc(II) monohydrate, [Zn(C₁₃H₁₅N₅)₂(C₂H₃O₂)₂]·H₂O, ( 1 ), and bis(azido‐κN¹)bis[1‐(1H‐benzotriazol‐1‐ylmethyl)‐2‐propyl‐1H‐imidazole‐κN³]zinc(II), [Zn(C₁₃H₁₅N₅)₂(N₃)₂], ( 2 ), constructed from the asymmetric multidentate imidazole ligand, have been synthesized under mild conditions and characterized by elemental analyses, IR spectroscopy and single‐crystal X‐ray diffraction analysis. Both complexes exhibit a three‐dimensional supramolecular network directed by different intermolecular interactions between discrete mononuclear units. The complexes were also investigated by fluorescence and thermal analyses. The experimental results show that ( 1 ) is a promising fluorescence sensor for detecting Fe³⁺ ions and ( 2 ) is effective as an accelerator of the thermal decomposition of ammonium perchlorate.     

Synthesis and structure of a 1-D copper(II) coordination polymer bridged both by oxamido and carboxylate: in vitro anticancer activity and reactivity toward DNA and protein BSA

A 1-D copper(II) coordination polymer formulated as {[Cu₂(bdpox)(dabt)](NO₃)·H₂O}_n, where H₃bdpox and dabt denote N-benzoate-N′-[3-(diethylamino)propyl]oxamide and 2,2′-diamino-4,4′-bithiazole, respectively, was synthesized and characterized by elemental analyses, molar conductance measurement, IR and electronic spectra studies, and single-crystal X-ray diffraction. The crystal structure analysis reveals that copper(II) ions are bridged by both cis-oxamido and carboxylato groups to form a 1-D coordination polymer with corresponding Cu···Cu separations of 5.2420(10) and 5.1551(8) Å. The endo- and exo-copper(II) ions of the cis-oxamido-bridge are located in distorted square-planar and square-pyramidal geometries, respectively. There is a 2-D hydrogen bonding network in the crystal. The in vitro anticancer activities suggest that the copper(II) complex is active against selected tumor cell lines. The reactivities toward herring sperm DNA and bovine serum albumin (BSA) reveal that the copper(II) complex can interact with DNA by intercalation and effectively quench the intrinsic fluorescence of BSA via a static mechanism. The influence of hydrophobicity of the substituents in bridging ligands on DNA and protein binding properties and the in vitro anticancer activities of such copper(II) polymers is discussed.     

3,6-Di-tert-butyl-o-benzosemiquinone complexes of copper(1) with bidentate bis(diphenylphosphine) ligands. Synthesis, structures, and properties

New mononuclear 3,6-di-tert-butyl-o-benzosemiquinone complexes of copper(1) with bis(diphenylphosphine) ligands were synthesized: (DBSQ)Cu(dppe) (1) (DBSQ=3,6-di-tert-butyl-o-benzosemiquinone and dppe=1,2-bis(diphenylphosphino)ethane), (DBSQ)Cu(dppp) (2) (dppp=1,3-bis(diphenylphosphino)propane), (DBSQ)Cu(dppn) (3) (dppn=2,2′-bis(diphenylphosphino)-1,1′-binaphthyl), and (DBSQ)Cu(dppfc) (4) (dppfc=1,1′-bis(diphenylphosphino)ferrocene). The compositions and structures of complexes1–4 were characterized by elemental analysis and electronic absorption, IR, and ESR spectroscopy. The molecular structures of complexes3 and4 were established by X-ray diffraction analysis. The reactions of elimination and replacement of neutral ligands in the coordination sphere of the complexes were studied by ESR spectroscopy. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2333–2340, November, 1998.     

Bis(triethanolamine)bis(μ2‐trimesato)dicobalt(II): a CoII dimer with an unreported two‐dimensional supramolecular topology formed from triethanolamine and trimesic acid ligands

Supramolecular networks are an important subset in the field of coordination polymer (CP) frameworks and are widely encountered in crystal engineering research. The search for novel topologies continues to be a significant goal in CP chemistry. The dimeric compound bis(μ‐5‐carboxybenzene‐1,3‐dicarboxylato‐κ²O¹:O³)bis[(triethanolamine‐κ⁴N,O,O′,O′′)cobalt(II)], [Co₂(C₉H₄O₆)₂(C₆H₁₅NO₃)₂], formed from the coligands 5‐carboxybenzene‐1,3‐dicarboxylate (tmaH²⁻) and triethanolamine (teaH₃), namely [Co(μ₂‐tmaH)(teaH₃)]₂, was synthesized and characterized by single‐crystal and powder X‐ray diffraction analyses, IR spectroscopy, thermogravimetric analysis (TGA) and magnetic measurements. The crystal structure features a zero‐dimensional molecular structure consisting of centrosymmetric macrocyclic dinuclear complexes. Four classical hydrogen bonds between carboxylate groups and hydroxyethyl arms stabilize and extend the molecules into a two‐dimensional supramolecular network. The topological analysis indicates that an unreported (3,5)‐binodal supramolecular topology with a short Schläfli symbol of (4.5.6)(4.5⁵.6³.7) can be achieved by means of intermolecular hydrogen bonds. The crystal structure accounts for the potential to obtain unique topological types from two excellent hydrogen‐bonding candidates, i.e. tmaH₃ and teaH₃. A variable‐temperature magnetic study shows the existence of antiferromagnetic behaviour in the complex.     

Bismuth(III) Complexes with N,N‐Di(2‐hydroxylethyl)aminodithiocarboxylate: Synthesis and Crystal Structure of {Bi[S2CN(C2H4OH)2]2[1, 10‐Phen]2(NO3)}·3H2O and (Bi[S2CN(C2H4OH)2]3}2

Two novel one‐ and two‐dimensional network structure bismuth(III) complexes with N, N‐di(2‐hydroxylethyl)‐aminodithiocarboxylate, {Bi[S₂CN(C₂H₄OH)₂]₂[1, 10‐Phen]₂(NO₃)}·3H₂O (1) and (Bi[S₂CN(C₂H₄OH)₂]₃)₂ (2) were synthesized. Their crystal and molecular structures were determined by X‐ray single crystal diffraction analysis. The crystal 1 belongs to monoclinic system with space group C2/c, a=1.6431(7) nm, b=2.4323(10) nm, c= 1.2646(5) nm, β=126. 237(5), Z=4, V=4.076(3) nm³, D_c=1.757 Mg/m^3, μ=4.598 mm^?1, F(000)=2156, R= 0.0211, wR=0.0369. The structure shows a distorted square antiprism configuration with eight‐coordination for the central Bi atom. The one‐dimensional chain structure was formed by H‐bonding interaction between hydroxyl group of N, N‐di(2‐hydroxylethyl)aminodithiocarboxylate ligands and crystal water. The crystal 2 belongs to monoclinic system with space group p2(1)/c, a= 1.1149(4) nm, b=2.1274(8) nrn, c=2.2107(8) nm, β=98.325(8)°, 2=4, V=5. 188(3) nm³, Dc=1.920 Mg/m³, μ=7.315 mm^?1, F(000)=2944, R=0.0565, wR=0.0772. The structure shows a distorted square antiprism configuration with eight‐coordination for the central Bi atoms. The two‐dimensional network structure was formed by H‐bonding interaction between adjacent molecules.     

1:1 and 1:2 Complexes of Mercury(II) Halides with 1,3-Thiazolidine-2-thione. Spectral, Thermal, and Crystal Structure Studies

The series of compounds of the general formulae HgX₂(tzdtH) and HgX₂(tzdtH)₂ (X = Cl, Br, I; tzdtH = 1,3-thiazolidine-2-thione) have been prepared, as well as Hg(tzdt)₂. IR, ¹H, and ¹³C NMR spectral data of the complexes indicate thione donation, which is confirmed by the crystal structure analyses of [HgBr₂(tzdtH)]₂, [HgI₂(tzdtH)]₂, and HgI₂(tzdtH)₂. The structures of [HgBr₂(tzdtH)]₂ and [HgI₂(tzdtH)]₂ consist of centrosymmetric doubly bridged dimers, but they are not isostructural. The asymmetry in the HgX₂Hg bridge is more pronounced in the bromo than in the iodo derivative [S–Hg–X(terminal) is 138.19(9)° for X = Br and 123.49(10)° for X = I], which is accompanied by the stronger Hg–S covalent bond in the bromo than in the iodo complex [2.435(4) vs. 2.510(3) Å]. The Hg–X(bridging) (X = Br, I) bond distances are shorter than the sum of van der Waals radii for mercury and X. Dimeric centrosymmetric complex units are held together only by van der Waals forces in [HgI₂(tzdtH)]₂, while in [HgBr₂(tzdtH)]₂ there is an intramolecular hydrogen bond of N–H Br type (3.34(1) Å). HgI₂(tzdtH)₂ exists as a mononuclear tetrahedral complex with two long Hg–S [2.672(1) Å] and two short Hg–I bond distances [2.688(1) Å] related by a twofold axis. The molecules of HgI₂(tzdtH)₂ are linked into infinite chains along the c axis by intermolecular N–H S [3.38(1) Å] hydrogen bonds.     

Synthesis and properties of nickel(ii) diiminodithiolate and diiminodisulfide N2S2-type complexes. New complexes with non-innocent ligands

The following two groups of nickel(ii) diiminodithiolate and diiminodisulfide N₂S₂-complexes were synthesized for the first time: (1) complexes with complete conjugation between all four donor centers, viz., compounds with non-innocent ligands, and (2) complexes containing a short conjugation system involving only two imino groups of the ligand. The complexes were studied by ¹H NMR, ESR, and UV spectroscopy, mass spectrometry, and electrochemistry. Solutions of glyoxal bis(2-mercaptoanil)nickel(ii) in DMF showed an ESR signal, which decreased with time, the processes being accompanied by an analogous change in the intensity of the absorption band at 931 nm. The electrochemical properties of this complex also change with time. The results of studies demonstrated that compounds with non-innocent ligands of this type were initially generated as classical diiminodithiolate structures, which were transformed into the ortho-iminothiosemiquinonate biradicals and then into oligomeric complexes both in solution (fast transformation) and in the solid state (slow transformation). Oligomeric structures of these compounds are stable for a long period of time.     

ChemInform Abstract: Synthesis and Characterization of Na6Cd7S10: A New Framework Sulfide with 1-D Channels Containing 12- and 16-Membered Rings and a Sulfide Anion in an Umbrella-Like Geometry.

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