共查询到20条相似文献,搜索用时 31 毫秒
1.
Antonio de León Josefina Pons Jordi García-Antón Xavier Solans Mercè Font-Bardía Josep Ros 《Polyhedron》2009
Mononuclear palladium(II) complexes containing a pyrazole-thioether ligand, with general formula trans-[Pd(X)2(bddo)] (X = CN− (1), SCN− (2) or N3− (3); bddo = 1,8-bis(3,5-dimethyl-1-pyrazolyl)-3,6-dithiaoctane), have been prepared. Similar reactivity carried out with pyridine or triphenylphosphine has been assayed. When pyridine is used, a mixture of [Pd(bddo)(py)2](BF4)2 ([4](BF4)2) and [Pd(bddo)](BF4)2 is obtained. When triphenylphosphine is used, only [Pd(bddo)](BF4)2 is obtained. The complexes have been characterised by elemental analyses, conductivity measurements, IR and NMR spectroscopies. X-ray crystal structure of trans-[Pd(SCN)2(bddo)] (2) is presented. In this complex the metal atom is coordinated by the two azine nitrogen atoms of the pyrazole rings and two SCN− anions in trans disposition. 相似文献
2.
Antonio de León Josefina Pons Jordi García-Antón Xavier Solans Mercè Font-Bardia Josep Ros 《Polyhedron》2007
The reaction between 1,2-bis[3-(3,5-dimethyl-1-pyrazolyl)-2-thiapropyl]benzene (bddf) and [MCl2(CH3CN)2] (M = Pd(II), Pt(II)) in a 1:1 M/L ratio in CH2Cl2 or acetonitrile solution, respectively, gave the complexes trans-[MCl2(bddf)] (M = Pd(II) (1), Pt(II) (4)), and in a 2:1 M/L ratio led to [M2Cl4(bddf)] (M = Pd(II) (2), Pt(II) (5)). Treatment of 1 and 4 with AgBF4 and NaBPh4, respectively, gave the compounds [Pd(bddf)](BF4)2 (3) and [Pt(bddf)](BPh4)2 (6). When complexes 3 and 6 were heated under reflux in a solution of Et4NBr in CH2Cl2/CH3OH (1:1) for 24 h, analogous complexes to 1 and 4 with bromides instead of chlorides bonded to the metallic centre were obtained. These complexes were characterised by elemental analyses, conductivity measurements, infrared, 1H, 1H{195Pt}, 13C{1H}, 195Pt{1H} NMR, HSQC and NOESY spectroscopies. The X-ray crystal structure of the complex [Pd(bddf)](BF4)2 · H2O has been determined. The metal atom is tetracoordinated by the two azine nitrogen atoms of the pyrazole rings and two thioether groups. 相似文献
3.
4.
Sofia I. Pascu Karl S. Coleman Nicholas H. Rees 《Journal of organometallic chemistry》2005,690(6):1645-1658
Treatment of the bulky iminophosphine ligand [Ph2PCH2C(Ph)N(2,6-Me2C6H3)] (L) with [M(CH3CN)2(ligand)]+n, where for M = Pd(II): ligand = η3-allyl, n = 1, and for M = Rh(I), ligand: 2(C2H4), 2(CO) or cod, n = 0, yields the mono-cationic iminophosphine complexes [Pd(η3-C3H5)(L)][BF4] (1), [Rh(cod)(L)][BF4] (2), [Rh(CO)(CH3CN)(L)][BF4] (3), and cis-[Rh(L)2][BF4] (4). All the new complexes have been characterised by NMR spectroscopy and X-ray diffraction. Complex 1 shows moderate activity in the copolymerisation of CO and ethene but is inactive towards Heck coupling of 4-bromoacetophenone and n-butyl acrylate. 相似文献
5.
Marino Basato Giacomo Facchin Mirto Mozzon Paolo Sgarbossa Augusto Tassan 《Journal of organometallic chemistry》2004,689(2):454-462
2-(Azidomethyl)phenyl isocyanide, 2-(CH2N3)C6H4NC (AziNC), coordinates to some cationic Pt(II) and Pd(II) species to afford isocyanide complexes of the type trans-[MCl(AziNC)(PPh3)2][BF4] (M=Pt, l; Pd, 2). AziNC is coordinated also in some neutral Pt(II) and Pd(II) species such as [MCl2(AziNC)2] (M=Pt, 3; Pd, 4) derived from the reactions of 2 equiv. of AziNC with [PtCl2(COD)] and [PdCl2(MeCN)2], respectively. Complexes 1 and 2 react with 1 equiv. of PPh3 affording the heterocyclic carbene complexes trans-[MCl{(H)}(PPh3)2][BF4] (M=Pt, 5; Pd, 6). Complexes 3 and 4 react with 1 equiv. of PPh3 displacing the isocyanide with the formation of the complexes cis-[MCl2(AziNC)(PPh3)] (M=Pt, 7; Pd, 8). These latter ones react with 2 equiv. of PPh3 affording as the final products the cationic carbene species trans-[MCl{(H)}(PPh3)2][Cl] (M=Pt, 9; Pd, 10). Complex 5 was also characterized by single crystal X-ray diffraction. The carbene complex is square-planar and the angle formed between the platinum square plane and the heterocyclic carbene ligand is 87.9(2)°. The C(1)-N(1) and C(1)-N(2) bond distances in the latter of 1.32(2) and 1.30(2) Å, respectively, are short for a single bond and indicate extensive π-bonding between the nitrogen atoms and the carbene carbon. 相似文献
6.
Rubén A. Machado María Cristina Goite Ysaura De Sanctis Antony J. Deeming Anibal Sierralta Teresa González 《Journal of organometallic chemistry》2007,692(4):894-902
The reaction of the labile compound [Re2(CO)8(CH3CN)2] with 2,3-bis(2-pyridyl)pyrazine in dichloromethane solution at reflux temperature afforded the structural dirhenium isomers [Re2(CO)8(C14H10N4)] (1 and 2), and the complex [Re2(CO)8(C14H10N4)Re2(CO)8] (3). In 1, the ligand is σ,σ′-N,N′-coordinated to a Re(CO)3 fragment through pyridine and pyrazine to form a five-membered chelate ring. A seven-membered ring is obtained for isomer 2 by N-coordination of the 2-pyridyl groups while the pyrazine ring remains uncoordinated. For 2, isomers 2a and 2b are found in a dynamic equilibrium ratio [2a]/[2b] = 7 in solution, detected by 1H NMR (−50 °C, CD3COCD3), coalescence being observed above room temperature. The ligand in 3 behaves as an 8e-donor bridge bonding two Re(CO)3 fragments through two (σ,σ′-N,N′) interactions. When the reaction was carried out in refluxing tetrahydrofuran, complex [Re2(CO)6(C14H10N4)2] (4) was obtained in addition to compounds 1-3. The dinuclear rhenium derivative 4 contains two units of the organic ligand σ,σ′-N,N′-coordinated in a chelate form to each rhenium core. The X-ray crystal structures for 1 and 3 are reported. 相似文献
7.
Elizaveta P. Shestakova Viktor N. Khrustalev Ivan S. Podkorytov Aleksei B. Nikolskii 《Journal of organometallic chemistry》2011,696(20):3214-3222
The oxidative addition of CH3I to planar rhodium(I) complex [Rh(TFA)(PPh3)2] in acetonitrile (TFA is trifluoroacetylacetonate) leads to the formation of cationic, cis-[Rh(TFA)(PPh3)2(CH3)(CH3CN)][BPh4] (1), or neutral, cis-[Rh(TFA)(PPh3)2(CH3)(I)] (4), rhodium(III) methyl complexes depending on the reaction conditions. 1 reacts readily with NH3 and pyridine to form cationic complexes, cis-[Rh(TFA)(PPh3)2(CH3)(NH3)][BPh4] (2) and cis-[Rh(TFA)(PPh3)2(CH3)(Py)][BPh4] (3), respectively. Acetylacetonate methyl complex of rhodium(III), cis-[Rh(Acac)(PPh3)2(CH3)(I)] (5), was obtained by the action of NaI on cis-[Rh(Acac)(PPh3)2(CH3)(CH3CN)][BPh4] in acetone at −15 °C. Complexes 1-5 were characterized by elemental analysis, 31P{1H}, 1H and 19F NMR. For complexes 2, 3, 4 conductivity data in acetone solutions are reported. The crystal structures of 2 and 3 were determined. NMR parameters of 1-5 and related complexes are discussed from the viewpoint of their isomerism. 相似文献
8.
Ta-Pin Tsai Yen-Tsang Huang Umasankar Ray Yin-Jui Chang Pei-Chi Cheng Chia-Jun Wu Jhy-Der Chen Ju-Chun Wang 《Polyhedron》2010
The syntheses and structures of a series of metal complexes, namely Cu2Cl4(L1)(DMSO)2·2DMSO (L1 = N,N′-bis(2-pyridinyl)-1,4-benzenedicarboxamide), 1; {[Cu(L2)1.5(DMF)2][ClO4]2·3DMF}∞ (L2 = N,N′-bis(3-pyridinyl)-1,4-benzenedicarboxamide), 2; {[Cd(NO3)2(L3)]·2DMF}∞ (L3 = N,N′-bis-(2-pyrimidinyl)-1,4-benzenedicarboxamide), 3; {[HgBr2(L3)]·H2O}∞, 4, and {[Na(L3)2][Hg2X5]·2DMF}∞ (X = Br, 5; I, 6) are reported. All the complexes have been characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. Complex 1 is dinuclear and the molecules are interlinked through S?S interactions. In 2, the Cu(II) ions are linked through the L2 ligands to form 1-D ladder-like chains with 60-membered metallocycles, whereas complexes 3 and 4 form 1-D zigzag chains. In complexes 5 and 6, the Na(I) ions are linked by the L3 ligands to form 2-D layer structures in which the [Hg2X5]− anions are in the cavities. The L2 ligand acts only as a bridging ligand, while L1 and L3 show both chelating and bridging bonding modes. The L1 ligand in 1 adopts a trans-anti conformation and the L2 ligand in 2 adopts both the cis-syn and trans-anti conformations, whereas the L3 ligands in 3–6 adopt the trans conformation. 相似文献
9.
The N4O3 coordinating heptadentate ligand afforded the mononuclear [FeIII(HL)][BPh4] (1) and binuclear [Fe2IIIL(OAc)2][BPh4] (2) complexes. In complex 1, the ligand binds in a trianionic N2O3 fashion whereas in the case of 2 the ligand binds in the trianionic N4O3 form in which the iron ions are held together by μ-phenoxo and bis μ-acetato bridges. In 1, the Fe(III) center has a trigonal bipyramidal geometry (τ = 0.84) whereas in 2 both the Fe(III) centers have a distorted octahedral geometry. Complex 2 shows an intramolecular weak antiferromagnetic interaction. Gas phase geometry optimizations have been performed using density functional theory without any symmetry constraints. The gas phase optimized structures agree well with the X-ray structure. 相似文献
10.
Sanjib K. Patra 《Journal of organometallic chemistry》2006,691(22):4779-4787
The Ru-Ru single bond in [Ru2(CO)4(MeCN)6][BF4]2 remains intact in the reaction with 2-i-propyl-1,8-naphthyridine (iPrNP) and the isolated product is the cis-[Ru2(iPrNP)2(CO)4(OTf)2] (1) obtained via crystallization in the presence of [n-Bu4N][OTf]. The 2-t-butyl-1,8-naphthyridine (tBuNP), on the contrary, leads to the oxidative cleavage of the Ru-Ru single bond resulting in the trans-[Ru(tBuNP)2(MeCN)2][BF4]2[NC(Me)C(Me)N] (2). The anti-[NC(Me)C(Me)N]2− is the product of the two-electron reductive coupling of two acetonitrile molecules. The phenoxo appendage in 2-(2-hydroxyphenyl)-1,8-naphthyridine (hpNP) brings the identical effect of the scission of the Ru-Ru bond but the process is non-oxidative and the product obtained is the cis-[Ru(hpNP)2(CO)2][BF4] (3). The bis-(diphenylphosphino)methane (dppm) in dichloromethane oxidatively cleave the Ru-Ru bond leading to chloro bridged [Ru(μ-Cl)(dppm)(CO)(MeCN)]2[BF4]2 (4). All the complexes have been characterized by the spectroscopic and electrochemical measurements and their structures have been established by X-ray diffraction study. 相似文献
11.
The preparation of 4′-(3,5-dimethylpyrazol-1-yl)-2,2′:6′,2″-terpyridine (2) under acidic conditions results in the formation of the salts [H22][MeOSO3]2 and [H22][EtOSO3]2, treatment of which with base leads to neutral 2. The structure of [H22][EtOSO3]2 · H2O has been established by single crystal X-ray diffraction. The complexes [Fe(2)2][PF6]2 and [Ru(2)2][PF6]2 have been prepared and characterized, and the single crystal structure determination of [Ru(2)2][PF6]2 is reported; [Fe(2)2][PF6]2 is isostructural with [Ru(2)2][PF6]2. Treatment of [Fe(2)2]2+ with PdCl2 produces [Pd(2)Cl]+, isolated and structurally characterized as the hexafluoridophosphate salt, illustrating that metal exchange within the tpy-binding domain occurs in preference to palladium(II) coordination by the N-donor atom of the pendant 3,5-dimethylpyrazol-1-yl unit in 2. [Pd(2)Cl]2+ can also be prepared from PdCl2 and [H22][MeOSO3]2 in refluxing methanol. 相似文献
12.
Pek Ke Chan 《Journal of organometallic chemistry》2008,693(15):2641-2644
Reaction of the iridium tetracarbonylate [PPN][Ir(CO)4] (1a) with triphenylcyclopropenyl tetrafluoroborate [C3Ph3][BF4] afforded two dinuclear species Ir2(CO)4(μ,η1:η2-C3Ph3)(μ,η2:η3-C3Ph3) (2) and Ir2(CO)4(μ,η4:η4-C6Ph6) (3a) resulting from the ring opening and in the latter case, coupling of the resulting acyclic, propenyl ligands. The analogous reaction with [PPN][Rh(CO)4] (1b) afforded only the rhodium analogue for 3a. 相似文献
13.
《Journal of organometallic chemistry》2005,690(8):1947-1958
The complexes [ReCl2{N2C(O)Ph}(Hpz)(PPh3)2] (1) (Hpz = pyrazole), [ReCl2{N2C(O)Ph}(Hpz)2(PPh3)] (2), [ReCl2(HCpz3)(PPh3)][BF4] (3) and [ReCl2(3,5-Me2Hpz)3(PPh3)]Cl (4) were obtained by treatment of the chelate [ReCl2{η2-N,O-N2C(O)Ph}(PPh3)2] (0) with hydrotris(1-pyrazolyl)methane HCpz3 (1,3), pyrazole Hpz (1,2), hydrotris(3,5-dimethyl-1-pyrazolyl)methane HC(3,5-Me2pz)3 (4) or dimethylpyrazole 3,5-Me2Hpz (4). Rupture of a C(sp3)-N bond in HCpz3 or HC(3,5-Me2pz)3, promoted by the Re centre, has occurred in the formation of 1 or 4, respectively. All compounds have been characterized by elemental analyses, IR and NMR spectroscopy, FAB-MS spectrometry, cyclic voltammetry and, for 1 · CH2Cl2 and 3, also by single crystal X-ray analysis. The electrochemical EL Lever parameter has been estimated, for the first time, for the HCpz3 and the benzoyldiazenide NNC(O)Ph ligands. 相似文献
14.
The C,N-(trimethylsilyliminodiphenylphosphoranyl)silylmethylmetal complexes [Fe(L)2] (3), [Co(L)2] (4), [ZrCl3(L)]·0.83CH2Cl2 (5), [Fe(L)3] (6), [Fe(L′)2] (7) and [Co(L′)2] (8) have been prepared from the lithium compound Li[CH(SiMe2R)P(Ph)2NSiMe3] [1a, (R = Me) {≡ Li(L)}; 1b, (R = NEt2) {≡ Li(L′)}] and the appropriate metal chloride (or for 7, FeCl3). From Li[N(SiMe3)C(Ph)C(H)P(Ph)2NSiMe3] [≡ Li(L″)] (2), prepared in situ from Li(L) (1a) and PhCN, and CoCl2 there was obtained bis(3-trimethylsilylimino- diphenylphosphoranyl-2-phenyl-N-trimethylsilyl-1-azaallyl-N,N′)cobalt(II) (9). These crystalline complexes 3-9 were characterised by their mass spectra, microanalyses, high spin magnetic moments (not 5) and for 5 multinuclear NMR solution spectra. The X-ray structure of 3 showed it to be a pseudotetrahedral bis(chelate), the iron atom at the spiro junction. 相似文献
15.
Condensation of (R)-2,2′-diamino-1,1′-binaphthyl or (R)-6,6′-dimethylbiphenyl-2,2′-diamine with 2 equiv of 2-pyridine carboxaldehyde in toluene in the presence of molecular sieves at 70 °C gives (R)-N,N′-bis(pyridin-2-ylmethylene)-1,1′-binaphthyl-2,2′-diimine (1), and (R)-N,N′-bis(pyridin-2-ylmethylene)-6,6′-dimethylbiphenyl-2,2′-diimine (3), respectively, in good yields. Reduction of 1 with an excess of NaBH4 in a solvent mixture of MeOH and toluene (1:1) at 50 °C gives (R)-N,N′-bis(pyridin-2-ylmethyl)-1,1′-binaphthyl-2,2′-diamine (2) in 95% yield. Rigidity plays an important role in the formation of helicate silver(I) complexes. Treatment of 1, or 3 with 1 equiv of AgNO3 in mixed solvents of MeOH and CH2Cl2 (1:4) gives the chiral, dinuclear double helicate Ag(I) complexes [Ag2(1)2][NO3]2 (4) and [Ag2(3)2][NO3]2 · 2H2O (6), respectively, in good yields. While under the similar reaction conditions, reaction of 2 with 1 equiv of AgNO3 affords the chiral, mononuclear single helicate Ag(I) complex [Ag(2)][NO3] (5) in 90% yield. [Ag2(1)2][NO3]2 (4) can further react with excess AgNO3 to give [Ag2(1)2]3[NO3]2[Ag(CH3OH)(NO3)3]2 · 2CH3OH (7) in 75% yield. All compounds have been fully characterized by various spectroscopic techniques and elemental analyses. Compounds 1 and 5-7 have been further subjected to single-crystal X-ray diffraction analyses. 相似文献
16.
Rosa M. Ceder Arnald Grabulosa Guillermo Muller Mercè Font-Bardía 《Journal of organometallic chemistry》2007,692(19):4005-4019
Optically active ligands of type Ph2PNHR (R = (R)-CHCH3Ph, (a); (R)-CHCH3Cy, (b); (R)-CHCH3Naph, (c)) and PhP(NHR)2 (R = (R)-CHCH3Ph, (d); (R)-CHCH3Cy, (e)) with a stereogenic carbon atom in the R substituent were synthesized. Reaction with [PdCl2(COD)2] produced [PdCl2P2] (1) (P = PhP(NHCHCH3Ph)2), whose molecular structure determined by X-ray diffraction showed cis disposition for the ligands. All nitrogen atoms of amino groups adopted S configuration. The new ligands reacted with allylic dimeric palladium compound [Pd(η3-2-methylallyl)Cl]2 to gave neutral aminophosphine complexes [Pd(η3-2-methylallyl)ClP] (2a-2e) or cationic aminophosphine complexes [Pd(η3-2-methylallyl)P2]BF4 (3a-3e) in the presence of the stoichiometric amount of AgBF4. Cationic complexes [Pd(η43-2-methylallyl)(NCCH3)P]BF4 (4a-4e) were prepared in solution to be used as precursors in the catalytic hydrovinylation of styrene. 31P NMR spectroscopy showed the existence of an equilibrium between the expected cationic mixed complexes 4, the symmetrical cationic complexes [Pd(η3-2-methylallyl)P2]BF4 (3) and [Pd(η3-2-methylallyl)(NCCH3)2]BF4 (5) coming from the symmetrization reaction. The extension of the process was studied with the aminophosphines (a-e) as well as with nonchiral monodentate phosphines (PCy3 (f), PBn3 (g), PPh3 (h), PMe2Ph (i)) showing a good match between the extension of the symmetrization and the size of the phosphine ligand. We studied the influence of such equilibria in the hydrovinylation of styrene because the behaviour of catalytic precursors can be modified substantially when prepared ‘in situ’. While compounds 3 and bisacetonitrile complex 5 were not active as catalysts, the [Pd(η3-2-methylallyl)(η2-styrene)2]+ species formed in the absence of acetonitrile showed some activity in the formation of codimers and dimers. Hydrovinylation reaction between styrene and ethylene was tested using catalytic precursors solutions of [Pd(η3-2-methylallyl)LP]BF4 ionic species (L = CH3CN or styrene) showing moderate activity and good selectivity. Better activities but lower selectivities were found when L = styrene. Only in the case of the precursor containing Ph2PNHCHCH3Ph (a) ligand was some enantiodiscrimination (10%) found. 相似文献
17.
Damir A. Safin Maria G. Babashkina Axel Klein Heinrich Nöth Michael Bolte Dmitriy B. Krivolapov 《Polyhedron》2010
Reaction of the potassium salt of N-(diisopropoxyphosphoryl)-p-bromothiobenzamide p-BrC6H4C(S)NHP(O)(OiPr)2 (HL) with Cd(II) cations in freshly dried and distilled EtOH leads exclusively to the complex [Cd(p-BrC6H4C(S)NH2-S)(L-O,S)2] ([Cd(LI)L2]), while the same reaction in H2O leads to the complex [Cd(HL-O)2(L-O,S)2] ([Cd(HL)2L2]). The corresponding reactions with Zn(II) always lead to the complex [Zn(L-O,S)2] ([ZnL2]) regardless of the solvent. The crystal structure of [Cd(HL)2L2].2/3H2O reveals to be a polymorph to the previously reported anhydrous [Cd(HL)2L2]. 相似文献
18.
Sergey A. Belov Dmitrii P. Krut’ko Dmitrii A. Lemenovskii Judith A.K. Howard 《Journal of organometallic chemistry》2008,693(10):1912-1918
Novel half-sandwich [C9H5(SiMe3)2]ZrCl3 (3) and sandwich [C9H5(SiMe3)2](C5Me4R)ZrCl2 (R = CH3 (1), CH2CH2NMe2 (2)) complexes were prepared and characterized. The reduction of 2 by Mg in THF lead to (η5-C9H5(SiMe3)2)[η5:η2(C,N)-C5Me4CH2CH2N(Me)CH2]ZrH (7). The structure of 7 was proved by NMR spectroscopy data. Hydrolysis of 2 resulted in the binuclear complex ([C5Me4CH2CH2NMe2]ZrCl2)2O (6). The crystal structures of 1 and 6 were established by X-ray diffraction analysis. 相似文献
19.
Shin-ichi NayaMakoto Nitta 《Tetrahedron》2003,59(21):3709-3718
Novel condensation reaction of tropone with N-substituted and N,N′-disubstitued barbituric acids in Ac2O afforded 5-(cyclohepta-2′,4′,6′-trienylidene)pyrimidine-2(1H),4(3H),6(5H)-trione derivatives (8a-f) in moderate to good yields. The 13C NMR spectral study of 8a-f revealed that the contribution of zwitterionic resonance structures is less important as compared with that of 8,8-dicyanoheptafulvene. The rotational barriers (ΔG‡) around the exocyclic double bond of mono-substituted derivatives 8a-c were obtained to be 14.51-15.03 kcal mol−1 by the variable temperature 1H NMR measurements. The electrochemical properties of 8a-f were also studied by CV measurement. Upon treatment with DDQ, 8a-c underwent oxidative cyclization to give two products, 7 and 9-substituted cyclohepta[b]pyrimido[5,4-d]furan-8(7H),10(9H)-dionylium tetrafluoroborates (11a-c·BF4− and 12a-c·BF4−) in various ratios, while that of disubstituted derivatives 8d-f afforded 7,9-disubstituted cyclohepta[b]pyrimido[5,4-d]furan-8(7H),10(9H)-dionylium tetrafluoroborate (11d-f·BF4−) in good yields. Similarly, preparation of known 5-(1′-oxocycloheptatrien-2′-yl)-pyrimidine-2(1H),4(3H),6(5H)-trione derivatives (14a-d) and novel derivatives 14e,f was carried out. Treatment of 14a-c with aq. HBF4/Ac2O afforded two kinds of novel products 11a-c·BF4− and 12a,c·BF4− in various ratios, respectively, while that of 14d-f afforded 11d-f. The product ratios of 11a-c·BF4− and 12a-c·BF4− observed in two kinds of cyclization reactions were rationalized on the basis of MO calculations of model compounds 20a and 21a. The spectroscopic and electrochemical properties of 11a-f·BF4− and 12a-c·BF4− were studied, and structural characterization of 11c·BF4− based on the X-ray crystal analysis and MO calculation was also performed. 相似文献
20.
Terézia Szabó-PlánkaJán Moncol Eszter TóthBéla Gyurcsik Nóra Veronika NagyZuzana Vasková Antal RockenbauerDušan Valigura 《Polyhedron》2011,30(14):2421-2429
EPR simulation method together with pH-potentiometry combined with UV-Vis spectrophotometry were used for the study of the ternary system 4-fuorosalicylic acid (HA)-N,N-diethylnicotinamide (B)-copper(II) in aqueous solution. The N,N-diethylnicotinamide ligand is a weak donor, its mixed-ligand complexes with 4-fluorosalicylate anions are more favoured. The number of coordinated N,N-diethylnicotinamide molecules increases with decreasing temperature: up to four ones were detected in the coordination sphere of copper(II) in frozen solutions. The formation of [CuH−1AB2] and [CuH−1A] was detected by all methods at neutral pH. At lower pH values, [CuA2B2] and [CuB] become dominant, and this fact is in good agreement with [CuA2B2(H2O)2] crystals obtained from similar solutions. The structural unit of the [CuA2B2(H2O)2] complex consists of a copper(II) ion, which is monodentately coordinated by a pair of 4-fluorosalicylate anions and by a pair of N,N-diethylnicotinamide in trans positions in the basal plane, and by two water molecules in the axial positions of a tetragonal bipyramid. 相似文献