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171.
172.
Crystals of dibromo-η5-cyclopentadienyltris(tetrahydrofuran)ytterbium(III) are monoclinic, P21/n (C2n5, No. 14), with a 15.310(15), b 16.900(17), c 7.968(8) Å, β 96.66(5)° and Z = 4. The ytterbium is pseudo-octahedrally coordinated by a cyclopentadienyl ligand, trans bromines, and mer tetrahydrofuran ligands, and the ytterbium—oxygen distance trans to cyclopentadienyl is longer than the other ytterbium—oxygen bonds. 相似文献
173.
The PMR and 19F NMR spectra of the complexes R2TlBr (R = C6F5, -HC6F4, -HC6F4, 3,5-H2C6F3, or 3,6-H2C6F3 and R3Tl(diox) (R = C6F5, -HC6F4, or 3,5-H2C6F3; diox = 1,4-dioxan) have been recorded. Proton and fluorine chemical shifts, thallium-proton, thallium-fluorine, fluorine-fluorine, and fluorine-proton coupling constants, and thallium substituent chemical shifts are given and discussed 相似文献
174.
Tetraphenylborate salts of solvated pentafluorophenyllanthanoid(II) cations [Ln(C(6)F(5))(thf)(n)](+) (Ln=Eu, n=6 (1); Ln=Yb, n=5 (2)) were readily synthesized in high yield by reactions of ytterbium or europium with HgPh(C(6)F(5)) and Me(3)NHBPh(4) in THF. The structures of 1.THF and 2 confirmed the existence of well-separated ions and both 1 and 2 show notable thermal stability at room temperature. The cation in 2 was also observed in the remarkable mixed-valent complex [Yb(II)(C(6)F(5))(thf)(5)][Yb(III)(C(6)F(5))(2)[N(SiMe(3))(2)](2)] (3), fortuitously isolated in low yield from a reaction of ytterbium metal, HgPh(C(6)F(5)), and HN(SiMe(3))(2) in THF, and which additionally has an unusual bis(pentafluorophenyl)bis[bis(trimethylsilyl)amido)]ytterbate(III) anion. (171)Yb-(19)F coupling has been observed in the low-temperature (171)Yb NMR spectra of 2 and [Yb(C(6)F(5))(2)(thf)(4)]. 相似文献
175.
The organomercury compounds HgR2 (R = 2-Cl,6-FC6H3, 2,6-F2C6H3, 2,3,6-F3C6H2, m-HC6F4, p-HC6F4, or C6F5) and RHg(O2CR) (R = 2-Cl,6-C6H3, 2,6-F2C6H3 or 2,3,6-F3C6H2) have been obtained in moderate – good and low yields respectively from decarboxylation reactions of the corresponding mercury(II) fluorobenzoates in boiling pyridine. By contrast, mercury(II) 2,3,4-5-tetrafluorobenzoate gave a low yield of CO2, a trace of Hg(o-HC6F4)2 and a very low yield of o-HC6F4Hg(O2CC6F4H-o). The 199Hg NMR spectra of the diorganomercurials (R = 2-Cl,6-FC6H3, 2,6-F2C6H3, 2,3,6-F3C6H2, 2,4,6-F3C6H2, 2,6-Cl2C6H3, o-HC6F4, m-HC6F4, p-HC6F4 or C6F5) are discussed. 相似文献
176.
Thomas Behrsing Glen B. Deacon Craig M. Forsyth Maria Forsyth Brian W. Skelton Allan H. White 《无机化学与普通化学杂志》2003,629(1):35-44
Reaction of CeCl3·7H2O with Na2(oda) (oda = O(CH2CO2)22— oxydiacetate) in a 2:3 ratio gives the neutral cerium(III) complex [Ce2(oda)3(H2O)3]·9H2O ( 1 ). Treatment of a 1:3 mixture of CeCl3·7H2O and H2oda in water with 4 molar equivalents of NaOH also gives 1 but, with a larger excess of NaOH, the tri‐sodium salt Na3[Ce(oda)3]·9H2O ( 2 ) is isolated. Formation of a tri‐ammonium analogue of 2 can be achieved by neutralisation of an aqueous solution of CeCl3·7H2O and H2(oda) in a 1:3 ratio by NH4OH, giving (NH4)3[Ce(oda)3]·7H2O ( 3 ). Use of the cerium(IV) reagent (NH4)2[Ce(NO3)6] with Na2(oda) results in reduction to cerium(III) under ambient conditions and isolation of 1 . However, in the absence of light this reaction yields crystals of the novel cerium(IV) heterobimetallic [Ce(oda)3Na4(NO3)2] ( 4 ). Each of these complexes exhibit a 3‐D network structure having a common nine‐coordinate [Ce(oda)3]n— (n = 2 or 3) subunit, irrespective of the oxidation state of cerium. In 1 , six [Ce(oda)3]3— anions are connected, through bridging bidentate carboxylates, to a second Ce3+ site further coordinated by three water molecules. In contrast, the ammonium salt 2 , displays isolated [Ce(oda)3]3— anions, devoid of further carboxylate bonding, but enmeshed within a network of hydrogen‐bonded NH4+ cations and water molecules. The remarkable structure of 4 consists of infinite 2‐D sheets of [Na2(NO3)]+ pillared by [Ce(oda)3]2— units, the connectivity arising by multidentate nitrate and carboxylate bridging. 相似文献
177.
Kepert CM Bond AM Deacon GB Spiccia L Skelton BW White AH 《Dalton transactions (Cambridge, England : 2003)》2004,(11):1766-1774
The reactions of bidentate diimine ligands (L2) with cationic bis(diimine)[Ru(L)(L1)(CO)Cl]+ complexes (L, L1, L2 are dissimilar diimine ligands), in the presence of trimethylamine-N-oxide (Me3NO) as a decarbonylation reagent, lead to the formation of heteroleptic tris(diimine) ruthenium(II) complexes, [Ru(L)(L1)(L2)]2+. Typically isolated as hexafluorophosphate or perchlorate salts, these complexes were characterised by UV-visible, infrared and mass spectroscopy, cyclic voltammetry, microanalyses and NMR spectroscopy. Single crystal X-ray studies have elucidated the structures of K[Ru(bpy)(phen)(4,4'-Me(2)bpy)](PF(6))(3).1/2H(2)O, [Ru(bpy)(5,6-Me(2)phen)(Hdpa)](ClO(4))(2), [Ru(bpy)(phen)(5,6-Me(2)phen)](ClO(4))(2), [Ru(bpy)(5,6'-Me(2)phen)(4,4'-Me(2)bpy)](PF(6))(2).EtOH, [Ru(4,4'-Me(2)bpy)(phen)(Hdpa)](PF(6))(2).MeOH and [Ru(bpy)(4,4'-Me(2)bpy)(Hdpa)](ClO(4))(2).1/2Hdpa (where Hdpa is di(2-pyridyl)amine). A novel feature of the first complex is the presence of a dinuclear anionic adduct, [K(2)(PF(6))(6)](4-), in which the two potassium centres are bridged by two fluorides from different hexafluorophosphate ions forming a K(2)F(2) bridging unit and by two KFPFK bridging moieties. 相似文献
178.
Pearson P Kepert CM Deacon GB Spiccia L Warden AC Skelton BW White AH 《Inorganic chemistry》2004,43(2):683-691
We report two new synthetic routes to the dinuclear Ru(I) complexes, [Ru(I)(2)(RCO(2))(CO)(4)(N( wedge )N)(2)](+) (N( wedge )N = 2,2'-bipyridine or 1,10-phenanthroline derivatives) that use RuCl(3).3H(2)O as a starting material. Direct addition of the bidentate diimine ligand to a methanolic solution of [Ru(CO)(2)Cl(2)](n) and sodium acetate yielded a mixture of [Ru(I)(2)(MeCO(2))(CO)(4)(N( wedge )N)(2)](+) (N( wedge )N = 4,4'-dmbpy, and 5,6-dmphen), and [Ru(II)(MeCO(2))(2)(CO)(2)(N( wedge )N)] (N( wedge )N = 4,4'-dmbpy and 5,5'-dmbpy). Single-crystal X-ray studies confirmed that the Ru(II) complexes had a trans-acetate-cis-carbonyl arrangement of the ligands. In contrast, the use of sodium benzoate resulted in the unexpected formation of a Ru-C bond producing ortho-cyclometalated complexes, [Ru(II)(O(2)CC(6)H(4))(CO)(2)(N( wedge )N)], where N( wedge )N = bpy or phen. A second approach used ligand exchange between a bidentate ligand (N( wedge )N) and the pyridine ligands of [Ru(I)(RCO(2))(CO)(2)(py)](2) to convert these neutral complexes into [Ru(I)(2)(RCO(2))(CO)(4)(N( wedge )N)(2)](+). This method, although it involved more steps, was applicable for a wider variety of diimine ligands (R = Me and N( wedge )N = 4,4'-dmbpy, 5,5'-dmbpy, 5,6-dmphen; R = Ph and N( wedge )N = bpy, phen, 5,6-dmphen). 相似文献
179.
180.
Georg Wolfbauer Alan M. Bond Glen B. Deacon Douglas R. MacFarlane Leone Spiccia 《Journal of Electroanalytical Chemistry》2000,490(1-2)
The electrochemical reduction of the black dye photosensitizer [(H3-tctpy)RuII(NCS)3]− (H3-tctpy=2,2′:6′,2′′-terpyridine-4,4′,4′′-tricarboxylic acid) used in photovoltaic cells has been found to be a complex process when studied in dimethylformamide. At low temperatures, fast scan rates and at a glassy carbon electrode, the chemically reversible ligand based one-electron reduction process [(H3-tctpy)Ru(NCS)3]−+e−[(H3-tctpy√−)Ru(NCS)3]2− is detected. This process has a reversible half-wave potential (Er1/2) of −1585±20 mV versus Fc/Fc+ at 25°C. Under other conditions, a deprotonation reaction occurs upon reduction, which produces [(H3−x-tctpyx−)Ru(NCS)3](1+x)− and hydrogen gas. Mechanistic pathways giving rise to the final products are discussed. The Er1/2-value for the ligand based reductions of the deprotonated complex is 0.70 V more negative than for [(H3-tctpy)Ru(NCS)3]−. Consequently, data obtained from molecular orbital calculations are consistent with the reaction [(H3-tctpy)Ru(NCS)3]−+e−→[(H2-tctpy−)Ru(NCS)3]2−+1/2H2 yielding the monodeprotonated complex as the major product obtained after electrochemical reduction of [(H3-tctpy)Ru(NCS)3]−. The Er1/2-values for the metal based RuII/III process differ by 0.30 V when data obtained for the protonated and deprotonated forms of the black dye are compared. Electronic spectra obtained during the course of experiments in an optically transparent thin layer electrolysis configuration are consistent with the overall reaction scheme proposed on the basis of voltammetric measurements and molecular orbital calculations. Reduction studies on the free ligand, H3-tcpy, are consistent with results obtained with [(H3-tctpy)Ru(NCS)3]−. 相似文献