Ruthenium(III) mono (2,2′-bipyridine) complexes containing O,O-donor ligands and their oxidation properties for organic compounds

The new complexes [Ru^IIIbpyL₂](PF₆) and [Ru^IIIbpyLCl₂] [bpy = 2,2-bipyridine; HL = acetylacetone, trifluoroacetylacetone, benzoylacetone (Hbac), tropolone or maltol; HL = Hbac or dibenzoylmethane) have been prepared and characterized by spectroscopy. Their redox behaviour was studied by cyclic voltammetry. They effectively catalyze the oxidation of alcohols, alkanes and primary aromatic amines.     

Synthesis, structure and properties of two bimetallic compounds [Co(bpy)2 (NiL)] (ClO4)2 and {[Co(phen)3](NiL)}(ClO4)2 containing a macrocyclic oxamide ligand

Two compounds, [Co(bpy)₂(NiL)](ClO₄)₂ (1)and {[Co(phen)₃](NiL)}(ClO₄)₂ (2), have been synthesized: (H₂L=2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacylotetradeca-7,12-diene, bpy=2,2-bypyridine and phen = 1,10-phenanthroline). Compound (1) contains a discrete binuclear [Co(bpy)₂(NiL)]²⁺ cation, while compound (2) is composed of [Co(phen)₃]²⁺ cations and NiL neutral fragments. The magnetic properties of compound (1) have been dealt with by isotropic one-ion approximation of the Co^II ion with a spin--orbit coupling in an O_h symmetry environment. The electronic spectra of these two compounds have also been discussed.     

ESR study of Jahn-Teller distortions and the structure of Cu(II) complexes in [Cu(bipy)2X](ClO4) and [Cu(phen)2X](ClO4)

The Cu(II) complexes in [Cu(bipy)₂X](ClO₄) and [Cu(phen)₂X](ClO₄) were studied by ESR spectroscopy at =9.8 GHz and optical absorption at 7000–20,000 cm^–1. The axially symmetrical g factors, corresponding to the g, were established for the distorted trigonal bipyramidal coordination of Cu(II) with C _2v symmetry. Analysis of the possible vibrational distortions of the complex showed that the axial symmetry of the g factor is a consequence of orientational averaging realized for an electronic vibrational state with a two-well adiabatic potential at the final height of the barrier and vibrational frequency greater than the ESR frequency.Slovakian Technical Institute and Institute of Geology and Geophysics, Siberian Branch, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 30, No. 5, pp. 74–77, September–October, 1989.     

Molecular and Supramolecular Structures of a Nickel(II)–Copper(II)–Nickel(II) Trinuclear Complex Containing a New Macrocyclic Oxamido Complex Ligand

The title complex, [Cu(NiL)₂(H₂O)₂](ClO₄)₂, has been obtained by self-assembly, where [NiL] is a new macrocyclic oxamido complex ligand. In the crystal, a new kind of supramolecular interaction between the carbon atoms of the oxamido group of each [NiL] complex ligand in a [Cu(NiL)₂(H₂O)₂]^{2 +} cation and the oxygen atom of one of the ester carbonyls of another [Cu(NiL)₂(H₂O)₂]^{2 +} cation, and C—HO, O—HO and interactions are observed and link the trinuclear fragments and perchlorate ions to form a 3D supramolecular network.     

O-phenylenebis(oxamato) bridged trinuclear copper(II) complexes: synthesis and magnetic properties

Summary Four new trinuclear copper(II) complexes bridged by o-phenylenebis(oxamato) (opba) and end-capped with 1,10-phenanthroline (phen), 5-nitro-1,10-phenanthroline (NO₂-phen), 2,2-bipyridyl (bipy) or 4,4-dimethyl-2,2-bipyridyl (Me₂bipy), {[Cu(opba)][Cu(L)]₂}(ClO₄)₂ (L = phen, NO₂-phen, bipy or Me₂bipy), have been synthesized and characterized. Based on i.r., elemental analyses, conductivity measurements and electronic spectra, oxamato-bridged structures consisting of three copper(II) ions in which each copper(II) ion has a square-planar environment are proposed. The temperature-dependent magnetic susceptibility of {[Cu(opba)][Cu(phen)]₂} (ClO₄)₂ has been studied in the 4.2–300 K range, giving the exchange integral J = -134.4cm^–1. The result revealed the operation of an antiferromagnetic spin-exchange interaction between the adjacent copper ions.     

Synthesis,Characterization, Electrochemical and Spectroscopic Properties of [Ru(dppt)(bpy)Cl]+ and [Ru(pta)(bpy)Cl]+

Two novel Ru^II complexes [Ru(dppt)(bpy)Cl]ClO₄ (1) and [Ru(pta)(bpy)Cl]ClO₄ (2)[dppt, pta and bpy = 3-(1,10-phenanthrolin-2-yl)-5,6-diphenyl-as-triazine, 3-(1,10-phenanthrolin-2-yl)-as-triazino[5,6-f]acenaphthylene and 2,2-bipyridine, respectively] were synthesized and characterized by elemental analysis and electrospray mass spectrometry, ¹H-n.m.r., and u.v.–vis spectroscopy. The redox properties of the complexes were examined using cyclic voltammetry. Due to the strong -accepting character of asymmetric ligands, the MLCT bands of (1) and (2) are shifted significantly to lower energies by comparison with [Ru(tpy)(bpy)Cl]⁺.     

Reactions of Tertiary Alcohols with Palladium(II) Tetraaqua Complex. Formation of Palladium π-Allyl Complexes

Transformations of 2-methyl-2-propanol, 2-methyl-2-butanol, 2-methyl-2-pentanol, 1-methyl-1-cyclohexanol, and 1-ethyl-1-cyclohexanol in the presence of tetraaquapalladium(II) ions in perchloric acid madium were studied. It was found that the reactions give rise to palladium(II) -allyl complexes. The reaction rate increases and the yield of the corresponding -allyl complex decreases with increasing hydrocarbon chain length. Addition of iron(III) ions to the systems essentially increases the yield of palladium -allyl complexes. The olefin formed from the corresponding tertiary alcohol participates in the formation of the palladium -allyl complex. Oxidation of 2-methyl-2-butanol with tetraaquapalladium(II) ions gives the isomeric palladium -allyl complexes [Pd(³-(CH₃)₂CCHCH₂)bpy]ClO₄ and [Pd(³-(CH₂C(CH₃)CHCH₃))bpy]ClO₄, which were isolated using 2,2'-bipyridyl and characterized by ¹H and ¹³C NMR spectroscopy.     

Carbonyl cationic rhodium(I) and iridium(I) complexes with sulphur donor and triphenylphosphine ligands

Summary The reaction of previously reported Rh^I and Ir^I cationic complexes towards carbon monoxide and triphenylphosphine has been studied. Carbonyl rhodium(I) mixed complexes of the formulae [Rh(CO)L₂(PPh₃)]ClO₄, (L=tetrahydrothiophene(tht), trimethylene sulfide(tms), SMe₂, or SEt₂), [(CO)(PPh₃)Rh{-(L-L)}₂Rh(PPh₃)(CO)](ClO₄)₂ (L-L= 2,2,7,7-tetramethyl-3,6-dithiaoctane (tmdto), (MeS)₂(CH₂)₃ (dth), or 1,4-dithiacyclohexane (dt), [Rh(CO)L(PPh₃)₂]ClO₄ (L= tht, tms, SMe₂, or SEt₂), and carbonyl iridium(I) complexes of the formulae [Ir(CO)₂(COD)(PPh₃)]ClO₄, [Ir(CO)(COD)(PPh₃)₂]ClO₄, [(CO)(COD)(PPh₃) Ir{-(L-L)} Ir(PPh₃)(COD)(CO)](ClO₄)₂ (L-L = tmdto or dt), [(CO)₂ (PPh₃)Ir(-tmdto)Ir(PPh₃)(CO)₂](ClO₄)₂, [(CO)₂(PPh₃) Ir(-dt)₂Ir(PPh₃)(CO)₂](ClO₄)₂, were prepared by different synthetic methods.     

Synthesis and magnetic properties of μ-oxalato-bridged Cu2 IIFeIII-type heterotrinuclear complexes

Three new -oxalato-bridged heterotrinuclear copper(II)–iron(III)–copper(II) complexes have been synthesized and identified: [Cu₂Fe(ox)₃L₂]ClO₄ [L = 5-nitro-1,10-phenanthroline (NO₂phen); 2,9-dimethyl-1,10-phenanthroline (Me₂phen) or 2,2-bipyridine (bpy), respectively]; ox = the oxalato dianions. Based on elemental analyses, molar conductivity and magnetic moment (at room-temperature) measurements, i.r. and electronic spectral studies, extended ox-bridged structures consisting of two copper(II) and an iron(III) ions, in which the central iron(III) ion has an octahedral environment and the end-capped two copper(II) ions a square-planar environment, are proposed for these complexes. The [Cu₂Fe(ox)₃(Me₂phen)₂]ClO₄ (1) and [Cu₂Fe(ox)₃(bpy)₂]ClO₄ (2) complexes were characterized further by variable-temperature magnetic susceptibility (4.2–300 K) measurements and the observed data were simulated by the equation based on the spin Hamiltonian operator, = –2J₁ · ₂, giving the exchange integrals J = –12.85 cm^–1 for (1) and J = –11.28 cm^–1 for (2). The results indicate the presence of an antiferromagnetic spin-exchange interaction between the copper(II) and iron(III) ions through the oxalato-bridge in both complexes (1) and (2).     

Naphthyl-(2-pyridylmethylene)amine complexes of silver(I) and ruthenium(II): synthesis,spectral studies and electrochemical behaviour

Pyridine-2-carboxaldehyde reacts with /-naphthylamine to give /-naphthyl-(2-pyridylmethylene)amine [-L (1), -L (2)]. L belongs to the unsymmetric diimine (—N=C—C=N—) family which can form five–membered chelate rings with metal ions. {donor centers are abbreviated as N[N(Py)] and N [N(nap)]} [Ag(L)₂]⁺ complexes were prepared and characterized by spectroscopic data. The reaction between L and RuCl₃ in boiling EtOH yielded green and blue–green compounds of composition RuCl₂(L)₂. I.r., u.v.–vis. and ¹H-n.m.r. data determined the stereochemistry of the complexes as trans-cis-cis (green) and cis-trans-cis (blue–green) according to the sequence of the coordination pair of Cl, N [N(Py)] and N [N(nap)]. Upon treatment of Ag(L)₂ ⁺ with Ru(bpy)₂Cl₂ in alcoholic suspension the ternary complexes, [Ru(bpy)₂(L)](ClO₄)₂, were isolated and characterized by spectroscopic data. [Ru(bpy)(L)₂](ClO₄)₂ complexes were synthesized similarly from ctc-Ru(L)₂Cl₂ and 2,2-bipyridine (bpy) in the presence of AgNO₃ and NaClO₄. These complexes show well-defined m.l.c.t transitions in the visible region. The sterochemistry of the complexes was established by ¹H-n.m.r. data. Cyclic voltammetry shows a high potential Ru^III/Ru^II couple and follows the order: [Ru(bpy)(L)₂]²⁺ > [Ru(bpy)₂(L)]²⁺ > Ru(-L)₂Cl₂ > Ru(-L)₂Cl₂.     

Synthesis and magnetism of 6-nitrobenzimidazolate and imidazolate-bridged copper(II) complexes

Summary Four new trinuclear copper(II) complexes, [Cu(phen)-(NBzIm)] (ClO₄) (1), [Cu(bpy)(NBzIm)](ClO₄) (2), [Cu-(Me₂-bpy)(NBzIm)](Ac)·1/2H₂O (3) and [Cu(Me₂-bpy)-(Im)](ClO₄)·1/2H₂O (4) (phen = 1, 10-phenanthroline, bpy = 2,2-bipyridine, NBzIm = 6-nitrobenzimidazolate ion, Im=imidazolate ion) have been prepared and characterized by variable temperature magnetic susceptibility measurements. A weak antiferromagnetic spin exchange interaction operates between copper(II) ions, exchange integrals evaluated as J =-23.82 cm^-1 for (1); and J=-21.91 cm^-1 for (2).     

Bi- and polynuclear organometallic complexes of palladium(II) with 4,4′-bipyridine

Summary Binuclear organometallic palladium complexes of the general formulae Pd₂[-(N-N)]R₂L₄(ClO₄)₂ and Pd₂[-(N-N)]Cl₂R₂L₂ [R = C₆F₅ or C₆CI₅; L = group VB or VIB ligand; (N-N') = 4,4-bipyridine] have been prepared by reacting the ligand (N-N) with compounds of the type Pd₂(-CI)₂R₂L₂ or PdOClO₃RL₂. Furthermore, polynuclear [PdR₂(N-N)]_x (R = Cl, C₆F₅ or C₆Cl₅) type complexes have been obtained by reaction of the ligand (N-N) with PdR₂(tht)₂, whilst treatment of [Pd₂(-CI)₂(C₆F₅)₄](NBu₄)₂ with an excess of (N-N) leads to the polynuclearcis-[Pd(C₆F₅)z(N-N)]_x species. Evidence for the structure of these compounds is obtained from their i.r. spectra.     

Unusually facile syntheses of [RuII(bpy)3]2+ (bpy = 2,2′-bipyridine) and [RuII(phen)3]2+ (phen = 1,10-phenanthroline)

The salts [Ru^II(L–L)₃](CF₃SO₃)₂ (L–L = bpy or phen) have been prepared in high yields via reactions of [Ru^II(DMF)₆](CF₃SO₃)₂ (DMF = N,N-dimethylformamide), generated in situ by reduction of [Ru^III(DMF)₆]-(CF₃SO₃)₃, with an excess of bpy or phen at room temperature in DMF solutions.     

Synthesis of γ-zirconium phosphate by the fluoro-complex method and the intercalation behavior of some α-diimines

The ammonium form of -zirconium phosphate has been synthesized by the direct precipitation method from fluorozirconate solution in the presence of ammonium dihydrogen phosphate. The hydrogen form Zr(HPO₄)₂ · 2H₂O, was obtained by acid treatment of the ammonium form -Zirconium phosphate , Zr(HPO₄)₂ · H₂O, with a relatively large particle size resulted from fluorozirconate solution in the presence of concentrated orthophosphoric acid. The intercalation behavior of such -diimines as 2,2-bipyridine (bpy) and 1,10-phenanthroline (phen) toward -zirconium phosphate was investigated, and it was found that about 0.2 mol of bpy and 0.5 mol of phen have been incorporated respectively per one mol of the host, with the expansion of interlayer distances. Further incorporation of Cu(H) ions into the interlayer space of these intercalates was possible. The bpy intercalate took up more Cu(II) ions than -zirconium phosphate, indicating that effective pillars are constructed between layers and the ion exchange of Cu(II) ions is facilitated thereby.     

4,4′-Dipyridyl and 2,2′-dipyridyl complexes of rare-earth perchlorates

4,4-Dipyridyl and 2,2-dipyridyl complexes of rare-earth perchlorates of the formulaLn(4-dipy)₈(ClO₄)₃HClO₄ · 4H₂O (Ln=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu, Y, 4-dipy=4,4-dipyridyl) andLn(2-dipy)₃(ClO₄)₃ · 6H₂O (Ln=Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu, Y, 2-dipy = 2,2-dipyridyl) have been synthesized. The IR spectra of these compounds and other physical properties are discussed.

---

4,4-Dipyridyl- und 2,2-Dipyridylkomplexe von Seltenerdmetallperchloraten

Zusammenfassung Es wurden 4,4-Dipyridylkomplexe des TypsLn(4-dipy)₈(ClO₄)₃HClO₄ · · 4 H₂O mitLn=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu, Y und 2,2-Dipyridylkomplexe des TypsLn(2-dipy)₃(ClO₄)₃ · 6 H₂O mitLn=Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu und Y dargestellt. Die IR-Spektren und andere physikalische Eigenschaften werden diskutiert.

     

A thermochemical study of cesium and nitrile perchloratozirconates

Measurements were carried out for the solution enthalpies of zirconium perchlorate, nitrile perchlorate, nitrile perchloratozirconate, and cesium perchloratozirconate in concentrated nitric acid. A thermochemical reaction cycle was established and the enthalpies of formation H_f ⁰ at 298.15 K were found for Zr(ClO₄)₄(s) (–745.5±2.7 kJ/mole), (NO₂)₂[Zr(ClO₄)₆](s) (–714.2±4.4 kJ/mole), and Cs₂[Zr(ClO₄)₆](s) (–1656.3±4.5 kJ/mole).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 910–913, April, 1990.     

Oxidation of isomeric η6- and η5-fluorenylchromiumtricarbonyl anions

The oxidation of the carbon-centered [(⁶-C₁₃H₉)Cr(CO)₃]^– anion (1 ^–) results in formation of (-⁶:⁶-9,9-bifluorenyl)bis-chromiumtricarbonyl (3) due to coupling of the intermediate carbon-centered radical (1^.). The oxidation of the metal-centered anion [(⁵-C₁₃H₉)Cr(CO)₃]^– (2 ^–), which is isomeric to the 1^– anion, gives an equilibrium mixture of the chromium-centered radical {(⁵-C₁₃H₉)Cr(CO)₃}^. (2 ^.) and its dimer [(⁵-C₁₃H₉)Cr(CO)₃]₂ (6). Radical2 ^. readily reacts with MeI and the solvent (THF); the resulting derivatives, (⁵-C₁₃H₉)Cr(CO)₃R (R=Me (10); R=H (7)), undergo fast ricochet inter-ring ⁵⁶ rearrangements into (⁶-9R-C₁₃H₉)Cr(CO)₃ (R=CH₃ (9); R=H (4)).Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1354–1358, July, 1995.The authors are grateful to D. V. Zagorevskii who recorded the mass spectra. This study was financially supported by the Russian Foundation for Basic Research (Grant No. 94-03-05209) and the International Science Foundation (Grant Nos. MQ 4000 and REV 000).     

Kinetics and mechanism of acetylene hydromethylation on organonickel catalysts

Kinetics of methane interaction with acetylene on Ziegler-Natta type organonickel catalysts has been studied. The reaction is first order with respect to methane. The kinetic isotope effect amounts to K_{CH 4}/K_{CD 4}=1.5 and K_{C 2}H₂,CH₄,H₂/K_{C 2}D₂,CD₄,D₂=2.0.

---

-. -. K_{CH 4}/K_{CD 4}, K_{C 2}H₂,CH₄,H₂/K_{C 2}D₂,CD₄,D₂ 1,5; 2,0. .

     

Synthesis of α,α′-bisdialkylphosphonoisopropylnitroxyls

Conclusions Some,-bisdialkylphosphonoisopropylnitroxyl radicals were obtained by the thermolysis of dialkyl -nitrosoisopropylphosphonates and isolated in the pure state.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1867–1868, August, 1979.     

Silver(I) complexes ofN-ethylthiourea. An infrared study

Summary The following silver(I) complexes ofN-ethylthiourea, L, have been isolated in the solid state: AgLX (X = Cl, Br, ClO₄, BF₄, and CF₃CO₂), Ag₂L₃X₂ (X=ClO₄, BF₄ and CF₃CO₂), AgL₂ClO₄, AgL₃X (X = Cl, Br, I, ClO₄, BF₄ and CF₃CO₂). The decrease of the(CS) and (SCN₂) frequencies in the i.r. spectra of the complexes indicates S-coordination of the ligands. The(AgS) frequencies lie in the 267–252 cm^–1 range for terminal and 240-210 cm^–1 range for bridged or long Ag-S bonds. The following structures may be proposed for the complexes. AgLX (X = Cl and Br), polymeric trigonal coordination with bridging halide ions; Ag₂L₃A₂ (A = ClO₄ and BF₄), polymeric trigonal coordination with three bridging sulphur atoms; AgL₂ClO₄, polymeric tetrahedral coordination with four bridging sulphur atoms; AgL₃A (A = ClO₄ and BF₄), dimeric tetrahedral coordination with two terminal and two bridging sulphur atoms; AgLO₂CCF₃ and Ag₂L₃(O₂CCF₃)₂, trigonal and/or tetrahedral coordination with terminal sulphur bonds and bridging CO₂ groups; AgL₃O₂CCF₃, tetrahedral coordination with terminal sulphur bonds and a monodentate CO₂ group. In the trifluoroacetato complexes, a(AgO) band is observed at 185–209 cm^–1. The AgL₃X complexes (X = Cl, Br and I) show two(AgX) and two(AgS) bands with rather low frequencies corresponding to long metal-ligand bond distances.