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32.
Min KS DiPasquale AG Golen JA Rheingold AL Arif AM Miller JS 《Journal of the American Chemical Society》2007,129(8):2360-2368
Dinuclear [(TPyA)MII(CA2-)MII(TPyA)]2+ [TPyA=tris(2-pyridylmethyl)amine; CA2-=chloranilate dianion; M=Co (1(2+)), Fe (2(2+))] complexes have been prepared by the reaction of M(BF4)(2).6H2O, TPyA, H2CA, and triethylamine in MeOH solution. Their reduced forms [(TPyA)MII(CA*3-)MII(TPyA)]+ [M=Co(1+), Fe (2+)] have been synthesized by using cobaltocene, and oxidized forms of 1, [(TPyA)CoIII(CAn)CoIII(TPyA)]z+ [z=3, n=3- (1(3+)); z=4, n=2- (1(4+))], have been obtained by using FcBF4 and ThianBF4 (Fc=ferrocenium; Thian=thianthrinium), respectively. The dinuclear compound bridged chloranilates (CA2- or CA*3-) were isolated and characterized by X-ray crystallography, electrochemistry, magnetism, and EPR spectroscopy. Unlike the other redox products, valence ambiguous 13+ forms via a complex redox-induced valence electron rearrangement whereby the one-electron oxidation of the [CoIICA2-CoII]2+ core forms [CoIIICA*3-CoIII]3+, not the expected simple 1-e- transfer mixed-valent [CoIICA2-CoIII]3+ core. The M ions in 1 and 2 have a distorted octahedral geometry by coordination with four nitrogens of a TPyA, two oxygens of a chloranilate. Due to the interdimer offset face-to-face pi-pi and/or herringbone interactions, all complexes show extended 1-D and/or 2-D supramolecular structures. The existence of CA*3- in 1(3+) is confirmed from both solid-state magnetic and solution EPR data. Co-based 1n+ exhibit antiferromagnetic interactions [1(2+): g=2.24, J/kB=-0.65 K (-0.45 cm-1); 1+: g=2.36, J/kB=-75 K (52 cm-1)], while Fe-based 2n+ exhibit ferromagnetic interactions [2(2+): g=2.08, J/kB=1.0 K (0.70 cm-1); 2+: g=2.03, J/kB=28 K (19 cm-1)] [H=-2JS1.S2 for 12+ and 2(2+); H=-2J(S1.S2+S2.S3) for 1+ and 2+]. Thus, due to direct spin exchange CA*3- is a much strong spin coupling linkage than the superexchange spin-coupling pathway provided by CA2-. 相似文献
33.
Mehrdad Pourayoubi James A. Golen Mahnaz Rostami Chaijan Vladimir Divjakovic Monireh Negari Arnold L. Rheingold 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(5):m160-m164
In the new tin(IV) and copper(II) complexes, cis‐dichlorido‐trans‐dimethyl‐cis‐bis(N,N′,N′′‐tricyclohexylphosphoric triamide‐κO)tin(IV), [Sn(CH3)2Cl2(C18H36N3OP)2], (I), and trans‐diaquabis(N,N′,N′′‐tricyclohexylphosphoric triamide‐κO)copper(II) dinitrate–N,N′,N′′‐tricyclohexylphosphoric triamide (1/2), [Cu(C18H36N3OP)2(H2O)2](NO3)2·2C18H36N3OP, (II), the N,N′,N′′‐tricyclohexylphosphoric triamide (PTA) ligands exist as hydrogen‐bonded dimers via P=O...H—N interactions around the metal center. The asymmetric unit in (I) consists of one complete complex molecule located on a general position. The SnIV coordination geometry is octahedral with two cis hydrogen‐bonded PTA ligands, two cis chloride ligands and two trans methyl groups. The asymmetric unit in (II) contains one half of a [Cu(PTA)2(H2O)2]2+ dication on a special position (site symmetry for the Cu atom), one nitrate anion and one free PTA molecule, both on general positions. The complex adopts a square‐planar trans‐[CuO2O2] coordination geometry, with the CuII ion coordinated by two PTA ligands and two water molecules. Each of the noncoordinated PTA molecules is hydrogen bonded to a neighboring coordinated PTA molecule and an adjacent water molecule; the phosphoryl O atom acts as a double‐H‐atom acceptor. The P atoms in the PTA ligands of both complexes and in the noncoordinated hydrogen‐bonded molecules in (II) adopt a slightly distorted tetrahedral environment. 相似文献
34.
Prof. Dr. Tarlok S. Lobana Poonam Kumari Gagandeep Bawa Geeta Hundal Ray J. Butcher Francisco J. Fernandez Jerry P. Jasinski James A. Golen 《无机化学与普通化学杂志》2012,638(5):804-810
Complexes of pyrrole‐2‐carbaldehyde thiosemicarbazones, [(C4H4N4)(H)C2=N3–N2(H)–C1(=S)–N1HR; R = Ph, H2L1; Me, H2L2; H, H2L3] with nickel(II) and palladium(II) are described. The reaction of nickel(II) acetate with H2L1 in methanol in 1:1 molar ratio yielded a complex of composition, [Ni(κ2‐N3,S‐HL1)2] ( 1 ). Likewise reaction of NiCl2 with H2L2 in 1:1 molar ratio in acetonitrile in the presence of triethylamine base followed by the addition of pyridine did not yield the anticipated [Ni(κ3‐N4,N3,S‐L2)(py)] complex, moreover a bis‐square‐planar complex, [Ni(κ2‐N3,S‐HL2)2] ( 2 ) was formed. However, in the presence of bipyridine (bipy), it yielded the addition product, [Ni(κ2‐N3,S‐HL2)2(κ2‐N, N‐bipy)] ( 3 ). Reaction of PdCl2(κ2‐P, P–PPh2–CH2–PPh2) with H2L3 in toluene in the presence of triethylamine has yielded a complex of stoichiometry, [Pd(κ3‐N4,N3,S–L3)(κ1‐P–PPh2–CH2–P(O)Ph2] ( 4 ). The ligands (HL1)– and (HL2)– are chelating to NiII metal atom as anions binding through N3,S‐donor atoms with pendant pyrrole groups, and (L3)2– is chelating to the PdII metal atom as dianion through N4,N3,S‐donor atoms (pyrrole is N4‐bonded). Fourth site in 4 is bonded to one P‐donor atom of PPh2–CH2–P(O)Ph2, whose pendant –PPh2 group involves auto oxidation to –P(O)PPh2 during reaction. These complexes were characterized using analytical data, IR, NMR (1H, 31P) spectroscopy and X‐ray crystallography. Complexes 1 , 2 , and 4 have square‐planar arrangement, whereas complex 3 is octahedral. 相似文献
35.
Daniel Mendoza-Espinosa Bernat A. Martinez-Ortega Mauricio Quiroz-Guzman James A. Golen Arnold L. Rheingold Tracy A. Hanna 《Journal of organometallic chemistry》2009,694(9-10):1509-1523
The synthesis, complete characterization, and solid state conformation of a new series of p-tert-butylcalix[5]arene (ButC5) mono-, di-, tri- and pentaanions are reported. X-ray structures of the alkali metal salts illustrate the strong influence of the alkali metal ion on the structure of the calixanion. The strength of the alkali metal base and its reaction stoichiometry play an important role in the conformation and level of deprotonation of the resulting anion. Reaction of ButC5 in a 2:1 molar ratio with alkali metal bases M2CO3 (M = Rb, Cs), or in a 1:1 ratio with M2CO3 (M = Na, K), MOH (M = Na, K, Rb, Cs) or MH (M = Li, Na) produces ButC5 monoanions, but ButC5 reacts in a 1:1 molar ratio with M2CO3 (M = Rb, Cs) or a 1:2 molar ratio with MOC(CH3)3 (M = Na, K) to afford ButC5 dianions. Due to the steric bulkiness of the But group no polymeric structures are observed. Alkali metal salts of trianionic ButC5 were obtained in high yields from reactions of ButC5 with MOC(CH3)3 (M = Li, Na, K), BunLi, LiH and LiOH in a 1:3 molar ratio. Pentaanionic ButC5 salts were obtained by the reaction with MOC(CH3)3 (M = Li, Na, K) or BunLi in a 5:1 ratio. X-ray crystal structures of ButC5 · Na and ButC5 · Cs indicate that the size of the alkali metal influences the level of cation-π arene interactions and therefore the conformation of the ButC5 unit; for example, ButC5 · Na has a cone conformation while ButC5 · Cs shows a flattened cone conformation. Cation-π arene interactions are observed in most of the calixarene salts. 相似文献
36.
Rabe GW Zhang-Presse M Riederer FA Golen JA Incarvito CD Rheingold AL 《Inorganic chemistry》2003,42(23):7587-7592
The syntheses and molecular structures of a number of terphenyl-based compounds of the lanthanide element samarium are reported. Reaction of 2 equiv of DppLi (Dpp = 2,6-diphenylphenyl) with 1 equiv of SmCl(3) in tetrahydrofuran at room temperature yields (Dpp)(2)SmCl(micro-Cl)Li(THF)(3) (1). The one-pot reaction of 1 equiv of K(2)COT (COT(2)(-) = cyclooctatetraenyl dianion) with 1 equiv SmCl(3) in tetrahydrofuran at room temperature followed by addition of 1 equiv of terphenyllithium salt DppLi, DmpLi (Dmp = 2,6-dimesitylphenyl), or DanipLi (Danip = 2,6-di(o-anisol)phenyl) produces DppSmCOT(micro-Cl)Li(THF)(3) (2), DmpSm(THF)COT (3), and DanipSm(THF)COT (4), respectively. In the case of the Danip-based compound 4 the order of addition of reagents can be reversed producing the same compound, however, in considerably lower yield. Compound 2 can also be prepared by reaction of 1 with 1 equiv of K(2)COT in tetrahydrofuran. The molecular structure of the bis(terphenyl) compound 1 exhibits a formally four-coordinate metal atom. The molecular structures of the terphenyl COT compounds 2-4 feature monomeric complexes which are obtained either as a lithium chloride adduct (2) or as tetrahydrofuran adducts (3, 4). In 4 the Danip ligand adopts the meso form. 相似文献
37.
Through the Weak-Link Approach, fluorescent condensed and open Cu(I) tweezer complexes were prepared and characterized. These complexes exhibit fluorescence-sensitive binding properties for halide anions. The solid-state structure of a non-fluorescent Rh(I) tweezer analogue, determined by X-ray crystallography, shows that the counter anion, Cl−, is trapped inbetween the two amide groups of the tweezer arms through hydrogen bonds. Although the tweezer binds Cl−, the open complex also binds Cl−, showing that the main role of the metal is to increase the local concentration of the pyrenyl amide moieties so that 2:1 binding can take place. 相似文献
38.
电感耦合等离子体原子发射光谱法测定钛酸钡纳米粉体中7种杂质元素 总被引:3,自引:0,他引:3
钛酸钡纳米粉体样品用盐酸溶解,在所得样品溶液中用电感耦合等离子体原子发射光谱法测定了以氧化物存在于样品中的7种杂质元素(包括镁、锶、钾、钠、铝、硅及铁),对测定的光谱条件进行了试验并优化达到上述各元素的测定上限为0.1%(质量分数).测得方法的检出限(3S/b)为(单位μg·L-1):2.0(铝),1.0(铁),20.0(钾),0.2(镁),4.0(钠),3.0(硅)及0.5(锶).应用此方法分析了两件实样,所得结果的相对标准偏差(n=6)小于等于2.0%,对其中4种杂质元素(镁、钾、钠和锶)同时用HG/T 3587-1999标准中的方法作分析校核,所得结果与此方法结果一致. 相似文献
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