AgI Complexes Research Articles

CVD of AgI Complexes with Tertiary Phosphines and Perfluorinated Carboxylates—A New Class of Silver Precursors

C2F5COOAgPMe3 (1) and C2F5COOAg (2) have been used as precursors for the CVD of silver layers in the temperature range 493–623 K. The thin films obtained were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), scanning tunneling electrochemical microscopy (STEM), X-ray photoelectron spectroscopy (XPS), and temperature variable infrared (IR) measurements. The SEM images of Ag films grown from 2 exhibited a surface with a grain size in the range 0.4–1.5 μm, whereas from 1 the size was ∼0.1 μm. This was confirmed by the STEM studies. The better stability of 1 in the vapor phase was proved by temperature variable IR spectra (373–523 K). Mass spectrometry (MS) images confirmed the presence of the monomeric and dimeric species, and the recombination ions transported in vapors. The XPS image analysis of the silver layers revealed the presence of some carbon impurities. The films demonstrated good adhesion to silicon substrates.

The Complexation Behaviour of Crown Ethers with Some Divalent Transition Metal and Silver Ions in a 40%(v/v) Ethanol + Water Medium

The stability constants in 40%(v/v) ethanol + water mixture were evaluated for complexes of NiII, CoII, CuII, ZnII, MnII and AgI with the macrocyclic polyethers 15-crown-5, benzo-15-crown-5, 18-crown-6 and dicyclohexano-18-crown-6 by conductometric titrations. In addition, a potentiometric study of the CuII and AgI complexes was undertaken to compare the results with those obtained by conductivity measurements. The complexation studies indicate 1:1 complex formation between the metal ion and crown ether and the log K values are in the range 1.0−3.0. The limiting molar conductivities of the metal ions and their crown ether complexes were also determined.

The Complexation Behaviour of Crown Ethers with Some Divalent Transition Metal and Silver Ions in a 40%(v/v) Ethanol + Water Medium

The stability constants in 40%(v/v) ethanol + water mixture were evaluated for complexes of NiII, CoII, CuII, ZnII, MnII and AgI with the macrocyclic polyethers 15-crown-5, benzo-15-crown-5, 18-crown-6 and dicyclohexano-18-crown-6 by conductometric titrations. In addition, a potentiometric study of the CuII and AgI complexes was undertaken to compare the results with those obtained by conductivity measurements. The complexation studies indicate 1:1 complex formation between the metal ion and crown ether and the log K values are in the range 1.0−3.0. The limiting molar conductivities of the metal ions and their crown ether complexes were also determined.

AuI and AgI Complexes with Tertiary Phosphines and Perfluorinated Carboxylates as Precursors for CVD of Gold and Silver

AuI and AgI Complexes with Tertiary Phosphines and Perfluorinated Carboxylates as Precursors for CVD of Gold and Silver

N-Functionalised heterocyclic carbene complexes of silver

N-Functionalised imidazol-2-ylidene carbene complexes of AgI have been prepared by interaction of the corresponding imidazolium salt with Ag2O in dichloromethane or 1,2-dichloroethane in the presence of molecular sieves or with Ag2CO3 in 1,2-dichloroethane. In an analogous way disilver(I) complexes of o-phenylenedimethylenebis(imidazol-2-ylidene) have been obtained. Their structures, as determined by X-ray crystallography, indicate that the carbene ligand acts as monodentate from the carbene end or as a bridge between two different metal atoms. In one case the silver is coordinated by two carbene ligands. In the majority of the structurally characterised complexes the metal centres adopt linear geometries with M–C(carbene) bond lengths in the range of 207–210 pm characteristic of a single bond.

A novel polymeric AgI complex consisting of two three-dimensional networks which are enantiometric and interpenetrating

One-pot reaction of AgNO3 and a large aromatic bridging ligand, diquinoxalino[2,3-a∶2′,3′-c]phenazine, which has three bidentate coordination sites, afforded a AgI complex consisting of two independent three-dimensional (3D) networks which are enantiometric and interpenetrating.

Effect of a metal ion on intramolecular spin exchange in spin-labeled complexes

The characteristic features of intramolecular spin exchange in 14 complexes of AgI, HgII, NiII, PdII, PtII, AuIII, and PtIV with spin-labeled ligands were studied by ESR spectroscopy. The measured values of the exchange integral ‖J‖ and the differences between the enthalpies of the efficient conformations (ΔH) were compared with the electronic polarization (refraction)R f of the NiII, PdII, and PtII ions and Klopman's rigidity parameters σK, which characterize the total polarazibility of the ions and the degree of covalence of the bond between the metal atom and the donor atom of the ligand, respectively. Delocalization of the electron spin density and the efficiency of spin exchange are determined by the relative contributions of the s, p, and d orbitals, which produce the overlap integral of wave functions, ‖J‖, and by the geometric features of the coordination polyhedron, which affect the mutual orientation of the N−O fragments.

Synthesis and Crystal Structure of 1,6-Bis(N,N-diethylthiocarbamoylimino)1,6-diphenyl-2.5-dithiahexane, its Dimeric AgI Complex [Ag2(C26H34N4S4)2](ClO4)2 · C7H8, and its Tetrameric μ-Tetrabromo AgI Complex [Ag4(C26H34N4S4)2Br4

Synthesis and crystal structure of 1,6-Bis-(N,N-diethylaminothiocarbamoylimino)-1,6-diphenyl-2,5-dithiahexane are reported as well as those of its dimeric AgI complex (as monotoluene adduct of the diperchlorate) and its tetrameric μ-tetrabromo AgI complex. Synthese und Kristallstruktur von 1,6-Bis(N,N-diethylthiocarbamoylimino)1,6-diphenyl-2.5-dithiahexan, seinem dimeren AgI-Komplex [Ag2(C26H34N4S4)2](ClO4)2 · C7H8 und seinem tetrameren μ-Tetrabromo-AgI-Komplex [Ag4(C26H34N4S4)2Br4] Die Synthese und Rontgenstrukturanalyse des potentiell vierzahnigen Schwefel-Chelatliganden 1,6-Bis-(N,N-diethylthiocarbamoylimino)-1,6-diphenyl-2,5-dithiahexan und seines dimeren 1 : 1 Silber(I)-Komplexes (als Diperchlorat) sowie seines tetrameren 1/2 : 1 : 1 Silber-Bromokomplexes werden beschrieben.

One-Step Syntheses of Polyhalogenometal Complexes by Direct Dissolution of the Metals in Halogen-Halide-Acetonitrile Systems

Abstract Polyhalogeno complexes of FeII, FeIII, NiII, CuI, CuII, ZnII, PdII, PdIV, AgI, SnII, SnIV, AuI, and AuIII are synthesized in one step by dissolving the corresponding metals in halogen-halide-acetonitrile systems.

Coordination Chemistry of Pentacarbonylrheniumacetylide Complexes with Copper, Silver, and Gold(I): (OC)5ReC≡CRe(CO)5 as Ligand

Dithioethyne (OC)5ReC≡CRe(CO)5 functions as an alkyne ligand in CuI, AgI, and AuI complexes to give bis(alkyne) complexes and dimetallatetrahedranes. The latter are bridged in 1 (R = Re(CO)5) and 2 (R = SiMe3) by difluorophosphate.

Open dimeric and capped polymeric container molecules: calixarene and resorcinarene complexes of AgI co-ordinated by participation of the upper-rim carbon atoms

The reactions of C-methylcalix[4]resorcinarene (L1), calix[6]arene (L2) and calix[4]arene (L3) with silver(I) salts have resulted in the isolation and structural characterization of three dimeric and one polymeric silver derivatives of calixarene based on cation π interactions. The dinuclear cation in [Ag2(L1)(C6H6)2][ClO4]2·5C4H8O 1 contains two symmetry-related metal centers, each involving a rather distorted tetrahedral co-ordination with, in addition to one benzene molecule, both the aryl OH groups and the aromatic rings of resorcinarene. The two dimeric calix[6]arene structures, {[Ag(L2)X]·2C6H6}2, where X = ClO4– 2 or CF3SO3– 3, display similar characteristics with two ligand groups inversely linked by the co-ordination of the silver ion to the phenyl carbons. The solvent molecules or the counter anions are not included in the cavity generated by the dimeric unit, but intercalated into calixarene or resorcinarene bilayers. In the calix[4]arene complex [Ag2(L3)(ClO4)2] 4 each of the four phenyl rings is bound to one metal atom which in turn bridges between the two calixarenes leading to an infinite two-dimensional arrangement. The polyoxo anion bridging between silver ions partially caps the container cavity of the calixarene. The factors controlling the selectivity of complexation and inclusion properties of calixarenes are discussed.

Molecular Dynamic and Conformational Study of an Unsaturated 12-crown-S 2 O 2 Ether and its Ag I Complexes

The preferred conformations and the complexional behaviour of mn-12S2O2 were studied by means of both NMR spectroscopy and molecular modelling. Furthermore, the AgI complexes of this ligand mn-12S2O2 were also studied by molecular mechanical calculations.

Enantioselective Formation of Double and Triple Helicates of Silver(I): The Role of Stacking Interactions

Despite having ligands with almost identical conformations, the structures of the AgI complexes of 1 and 2 differ significantly: ligand 1 forms a double-helical complex of P chirality, and 2 gives a triple-helical complex (depicted on the right). The reason for the difference appears to be the existence of strong interligand stacking in the latter case.

Mononuclear and binuclear chelates derived from potassium benzenesulfonyldithiocarbazate

Benzenesulfonyldithiocarbazate (PhSO2NHNHCSS−) (HBDC−) complexes of CoII, NiII, ZnII, CdII, PdII, PbII, CuI and AgI have been prepared and characterized by elemental analyses, molar conductivities, spectral (vis., i.r, n.m.r.), thermal (t.g.a., d.t.a.) and magnetic moment measurements. The molar conductivities for the complexes lie in the non-electrolyte range. The i.r. spectral data indicate that KHBDC behaves either as monoanionic bidentate or dianionic tridentate ligand. The O=S=O group participates in bonding via bridge formation in dimeric (1:1) complexes. Different stereochemistries are proposed for the CoII, NiII and PdII complexes on the basis of the spectral and magnetic studies. T.g.a. and d.t.a. data suggest a mechanism for degradation of the complexes as a function of temperature.

Silver(I) Sandwich Complexes of Oxa‐Crowned Derivatives of Dithiomaleonitrile

AbstractThe coordination chemistry of the four oxa‐crowned derivatives of dithiomaleonitrile mn‐12S2O2, mn‐15S2O3, mn‐18S2O4, and mn‐21S2O5 as well as of the acyclic bis(methylthio)maleonitrile mn‐S2 with AgI was investigated by X ray structural and spectroscopic methods. The 2:1 complexes (ligand/AgI) [Ag(mn‐12S2O2)2]PF6, [1]PF6, [Ag(mn‐15S2O3)2]PF6, [2]PF6, and [Ag(mn‐S2)2]PF6, [6]PF6, and the 1:1 complexes [Ag(mn‐15S2O3)]ClO4, [3]ClO4, [Ag(mn‐18S2O4)]PF6, [4]PF6, and [Ag(mn‐21S2O5)]PF6 [5]PF6, were obtained with AgPF6 or AgClO4 in MeOH. The stoichiometry of the macrocyclic AgI complexes and the coordination mode of mn‐S2On+1 coronands (n = 1–4) is determined by the length of the macrocyclic oligoethylene chain. – The mn‐crown dithioethers mn‐12S2O2 and mn‐15S2O3 form with AgPF6 the new sandwich complexes [Ag(mn‐12S2O2)2]PF6, [1]PF6, and [Ag(mn‐15S2O3)2]PF6, [2]PF6. [1]PF6 crystallises in the triclinic space group P1. In the centrosymmetric cation [1]+ each mn‐12S2O2 ligand is coordinated to the AgI centre in an endo manner via both S atoms and one O atom. The distance of the second O atom of mn‐12S2O2 to AgI is somewhat longer than a normal Ag–Oether bond. The overall environment around AgI in [1]+ is that of a distorted cubic S4O4 set of donors. [2]PF6 crystallises in the monoclinic space group C2/c. In the centrosymmetric cation [2]+ silver(I) is planar‐coordinated by the four S atoms of both mn‐15S2O3 molecules. The six O atoms of both mn‐15S2O3 ligands show only long‐range interactions to the AgI ion. They surround AgI almost vertically to the planar S4 set of donors in a crown‐like manner. – The crystal structures of the 1:1 complexes [Ag(mn‐18S2O4)]PF6, [4]PF6, and [Ag(mn‐21S2O5)]PF6, [5]PF6, consist of linear chain polymers. [5]PF6 forms an N‐bridged chain polymer of endocyclic [Ag(mn‐21S2O5)]+ units with S1O4NNitrile coordination at the AgI centre. In the 2:1 complex [Ag(mn‐S2)2]PF6, [6]PF6, each mn‐S2 acts as a monodentate NNitrile donor. – 13C‐NMR studies in nitromethane solution confirm that the AgI ions in the complexes of the mn‐crown dithioethers remain coordinated. However, the AgI ion in complex of mn‐S2 is decoordinated.

2,4′-Bipyridyl complexes with silver(I) and copper(II)

AgI and CuII complexes with 2,4′-bipyridyl (2,4′-bipy or L) with the general formulae AgL2X (where X = NO inf3 sup− or ClO4 -), CuL2X2·2H2O (X = Cl- or Br-), CuL4SO4·4H2O, CuL4(NO3)2·2H2O and CuL4(ClO4)2·H2O have been isolated pure and characterized by analytical, spectral and magnetic measurements. The thermal decomposition of these complexes was studied under non-isothermal conditions in air.

Synthesis, structure and characterization of binuclear silver(I) complexes

Two binuclear AgI complexes, [{Ag(dppp)}2](NO3)2 (1) and [{Ag(dppb)}2(NO3)]2 (2) (dppp = Ph2P(CH2)3PPh2, dppb = Ph2P(CH2)4PPh2], were synthesized and characterized by elemental analysis, t.g., i.r. and 31P-n.m.r. spectra. Single crystals of complex (2) were obtained from MeOH-CHCl3. The X-ray crystal structure shows that the dppb ligand is bidentate, with two ligands bridging two metal ions to form a centrosymmetric dimer.

Radical cations of benzo[a]pyrene and 6-substituted derivatives: reaction with nucleophiles and DNA.

1. Oxidation of benzo[a]pyrene (BP) by I2 in the presence of AgClO4 in benzene generates the BP.+ClO4-.AgI complex. This same method was used to produce radical cations from 6-FBP, 6-ClBP, 6-BrBP and 6-CH3BP. 2. Reaction of the BP, 6-FBP, 6-ClBP and 6-BrBP radical cation perchlorates with H2O produced BP 1,6-, 3,6- and 6,12- dione, whereas 6-CH3BP.+ClO4-.AgI yielded 6-CH2OHBP. 3. When BP.+ClO4-.AgI and 6-FBP.+ClO4-.AgI were reacted with NaOAc in H2O/CH3CN (9:1), 6-OAcBP was formed, in addition to the quinones. In the case of 6-ClBP.+ClO4-.AgI, a small amount of 1-OAc-6-ClBP and 3-OAc-6-ClBP was formed in addition to the diones, whereas for 6-BrBP and 6-CH3BP the reaction products were BP diones and 6-CH2OHBP respectively. 4. These results confirm the localization of charge in the BP.+ at C-6, followed by C-1 and C-3. 5. The reaction of BP with NOBF4 in CH2Cl2 produced BP.+BF4-, radical cation free of complexation with inorganic salts. 6. Reaction of BP.+BF4- with DNA produced the depurinating adducts BP-6-C8Gua, BP-6-C8dGua and BP-6-N7Gua.

Studies on the Thermal Stability of Cu(I) and Ag(I) Complexes - II. Mixed-Ligand Complexes of CuI and AgI with Thiourea and Heterocyclic Amines

Abstract The thermal behaviour of some mixed-ligand complexes of Cu(I) and Ag(I) formed by the interaction of Cu(tu)3I and Ag(tu)I (where tu stands for thiourea) with py, 2-pic, 3-pic, 4-pic, qu, iqu, pip, ac, bpy and phen have been studied using TGA and DTA techniques. IR spectral and X-ray diffraction analyses have been employed to identify the nature of the dissociation products. The Cu (I) complexes lose thiourea in the first step and then the heterocyclic amine whereas in case of the Ag(I) complexes, the thiourea molecule leaves only after the removal of the heterocyclic amine from the complex. The thermal behaviour of the complexes shows that Cu (I) is more tenaciously bonded with nitrogen donors whereas Ag(I) has more affinity towards sulphur containing ligands.

Synthesis, complexation behaviour and reactions of thia-crown ethers incorporating propan-2-one units

Thia-crown ethers containing ketone functionality derived from 1,3-dichloroacetone have been prepared in 70–80% yields; the crystal structures of one free macrocycle and two AgI complexes have been determined.