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1.
Equilibria occurring between glycine (L) and magnesium(II) and calcium(II) were studied by measuring at 25 °C the electromotive force (e.m.f.) of the cell: (–) Pt, H2/SolutionS/R.E. (+) where R.E. is the reference electrode described in the text.Equilibria taking place in solutions containing iron(II) and glycine were investigated by means of the cell: (–) R.E./SolutionS/G.E. (+) where G.E. is the glass electrode. The general composition of solutionS was in both cases the following: B M inM 2+;H M in H+;A M inL; 3.00M in ClO 4 ; (3-H-2B)M in Na+.Experimental data were explained by assuming the existence of the species:: MgL(log 1,0,1=1.53±0.05); MgL 2(log 2,0,1=2.26±0.05); CaL(log 1,0,1==0.75±0.03); FeL(log 1,0,1=4.20±0.04).Protonation constants of aminoacetate, not known in the experimental conditions selected, were determined by means of e.m.f. measurements carried out with a H2 electrode.
Komplexbildung zwischen Glycin und Magnesium(II), Calcium(II), bzw. Eisen(II) bei 25 °C in 3,00M NaClO4
Zusammenfassung Die Gleichgewichte zwischen Glycin (L) und Magnesium(II) bzw. Calcium(II) wurden bei 25 °C durch E.M.K. Messungen der folgenden Meßkette untersucht: (–) Pt, H2/ProbenlösungS/R.E. (+) wobei R.E. Referenz-Elektrode bedeutet (siehe Text).Zum Studium der Reaktion zwischen Eisen(II) und Glycin bei 25 °C wurde folgende Meßkette benutzt: (–) R.E./ProbenlösungS/G.E. (+) wobei G.E. Glas-Elektrode bedeutet.Alle Meßproben hatten die folgende allgemeine Zusammensetzung:B M inM 2+;H M in H+;A M inL; 3,00M in ClO 4 ; (3-H-2B)M in Na+.Die experimentellen Daten konnten unter Annahme folgender Komplexe erklärt werden: MgL(log 1,0,1=1,53±0,05); MgL 2(log 2,0,1=2,26±0,05); CaL(log 1,0,1=0,75±0,03); FeL(log 1,0,1=4,20±0,04). Die Protonierungskonstanten von Aminoacetat, die bei den gewählten experimentellen Bedingungen nicht bekannt sind, wurden mittels E.M.K. Messungen (mit Wasserstoff-Elektrode) bestimmt.
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2.
Several trans-hydridomethylbis(phosphine)-platinum(II) and -palladium(II) complexes have been made by the reaction: trans-M(H)Cl(PR3)2 + CH3MgBr → trans-M(CH3)(PR3)2 + MgClBr and their structures determined by 1H NMR and IR spectroscopy. The complexes in which M  Pt and R  Cy (cyclohexyl) or i-Pr (isopropyl) are very stable in the solid state and in solution, while the compounds in which M  Pt, R  Et (ethyl) and M  Pd, R  i-Pr slowly decompose either in the solid state or in solution. The compound in which M  Pd and R  Cy was not isolated but was identified in solution.  相似文献   

3.
Summary Complexes of the type M(AcLeu)2 · B2 (M = CoII, NiII or ZnII; B = H2O, py, 3-pic, 4-pic; AcLeu =N-acetyl-DL-leucinate ion) and M(AcLeu)2 B (M = CoII or ZnII and B = o-phen) were prepared and investigated by means of magnetic and spectroscopic measurements. The i.r. spectra of all the complexes are consistent with bidentate coordination of the amino acid to the metal ion. The room temperature solid state electronic spectra indicate that the symmetry of this species is closer toD 4h and that MO6 and MO4N2 chromophores are present in the M(AcLeu)2 · 2 H2O and M(AcLeu)2Bn · x H2O (B = py, 3-pic, 4-pic, n=2 and x=0 for M = NiII; B = o-phen, n=1 and x=0 for M = CoII; B = py, 3-pic, 4-pic, n=1 and x=1 for M = CoII) complexes, respectively. By comparing the Dq values of the amino acid and those of other N-substituted amino acids previously studied, a spectrochemical series of the the cobalt(II) and nickel(II) complexes is proposed. The1 H n.m.r. spectra of the zinc(II) complexes confirm the proposed stereochemistry.  相似文献   

4.
The stereodynamics of ferrocenylsulphide-palladium(II) and -platinum(II) complexes, Fe(C5H4SR)2MX2, (M = PdII, PtII; X = Cl, Br; R = Ph, i-Pr and i-Bu), have been examined by variable temperature NMR. At temperatures down to ca. ?100° C, the pyramidal inversion of the S atoms could be slowed down sufficiently to yield accurate energy data, while the reversal of the ferrocenophane ring remained fast on the NMR time scale. ΔG data for the S inversion process were in the range 47 to 65 kJ mol?1 and were influenced to varying extents by the nature of the transition metal, the halogen, and the R substituent on the sulphur.  相似文献   

5.
Novel neutral biimidazolate or bibenzimidazolate palladium(II) and platinum(II) complexes of the type M(NN)2(dpe) [M = Pd, Pt; (NN)22? = BiIm2?, BiBzIm2?. dpe = 1,2-bis(diphenylphosphino) ethane] have been obtained by reacting MCl2(dpe) with TI2(NN)2. Complexes M(NN)2(dpe) which are Lewis bases react with HClO4 or [M(dpe)(Me2CO)2](ClO4)2 to yield, respectively, mononuclear cationic complexes of general formula [M{H2(NN)2](dpe) (M = Pd, Pt; H2(NN)2 = H2BiIm, H2BiBzIm) and homobinuclear palladium(II) or platinum(II) cationic complexes of the type [M2{μ - (NN)2}(dpe)2](ClO4)2. Reactions of M(BiBzIm)(dpe) with [Rh(COD) (Me2CO)X](ClO4) render similar heterobinuclear palladium(II)-rhodium(I) and platinum(II)-rhodium(I) cationic complexes, of general formula [(dpe)M(μ-BiBzIm)Rh(COD)](ClO4) (M = Pd, Pt; COD = 1,5-cyclooctadiene). Di- and mono-carbonyl derivatives [(dpe)M(μ-BiBzIm)Rh(CO)L](ClO4) (M = Pd, Pt; L = CO, PPh3) have also been prepared. The structures of the resulting complexes have been elucidated by conductance studies and IR spectroscopy.  相似文献   

6.
Complexes with Macrocyclic Ligands. IV. Heterodinuclear Cobalt(II), Nickel(II), Copper(II), Zinc(II) and Palladium(II) Complexes with a Macrocyclic Ligand of Schiff‐Base Type: Syntheses and Structures The synthesis and properties of nickel(II), copper(II), and palladium(II) complexes, [MLPh] ( 3 ; LPh = N,N′‐phenylene‐bis(3‐formyl‐5‐tert.‐butyl‐salicylaldimine)), are described. These neutral mononuclear complexes react with metal(II) perchlorate and 1,3‐propylenediamine to form heterodinuclear, macrocyclic, cationic complexes of the type [MM′(LPh,3)]2+ ( 4 ; M = Ni, Cu, Pd; M′ = Co, Cu, Zn). The structures of the five new compounds [NiCo(LPh,3)](ClO4)2, [NiCu(LPh,3)](ClO4)2, [CuCu(LPh,3)](ClO4)2, [CuZn(LPh,3)](ClO4)2, and [PdCu(LPh,3)](ClO4)2 were determined by X‐ray diffraction.  相似文献   

7.
Phosphido- and Arsenido-bridged Dinuclear Complexes. Synthesis and Molecular Structure of (η5-C5H4R)2Zr{μ-P(SiMe3)2}2M(CO)4 (R = Me, M = Cr; R = H, M = Mo) and Synthesis of (η5-C5H5)2Zr{μ-As(SiMe3)2}2Cr(CO)4 The reaction of (η5-C5H4R)2Zr{E(SiMe3)2}2 with M(CO)4(NBD) (NBD = norbornadiene) yields the dinuclear phosphido- or arsenido-bridged complexes (η5-C5H4R)2Zr{μ-E(SiMe3)2}2M(CO)4 (R = Me, E = P, M = Cr ( 1 ); R = H, E = P, M = Mo ( 2 ); R = H, E = As, M = Cr ( 3 )). No formation of dinuclear complexes was observed in the reaction of (η5-C5H4Me)2Zr{P(SiMe3)2}2 with Ni(PEt3)4, Ni(CO)2(PPh3)2 or with NiCl2(PPh3)2 in the presence of Mg. Complexes 1 – 3 were characterised spectroscopically (i. r., n. m. r., m. s.), and X-ray structure investigations were carried out on 1 and 2 . The central four-membered ZrP2M ring is slightly puckered (dihedral angle between planes ZrP2/CrP2 14.7°, ZrP2/MoP2 14.2°). The Zr? P bond lengths are equivalent ( 1 : Zr? P1 2.654(4), Zr? P2 2.657(4) Å; 2 : Zr? P1 2.6711(9), Zr? P2 2.6585(7) Å), as are the M? P bond lengths (M = Cr ( 1 ): Cr? P1 2.513(4), Cr? P2 2.502(4) Å; M = Mo ( 2 ): Mo? P1 2.6263(7), Mo? P2 2.6311(10) Å). The long Zr ··· M distances of 3.414 Å (M = Cr ( 1 )) and 3.461 Å (M = Mo ( 2 )) indicate the absence of a metal-metal bond.  相似文献   

8.
Complexes of 2,6-dimethyl-3,5-pyridinedicarboxylic acid dihydrazide (DH) with copper(II) and cobalt(II) nitrates and sulfates have been studied by IR and UV spectroscopy, DTA, and X-ray crystallography. The complexation results in polynuclear compounds of the {[M(DH)(ROH) n ]An m } z composition (M = Cu2+, Co2+; An = SO42−, NO3; R = H, i-Pr; n = 0.5–4, m = 1.2, z ≥ 4) containing bidentate DH bridges coordinated to the metal through the carbonyl oxygen atom and the amino group nitrogen atom of the hydrazide moiety.  相似文献   

9.
Synthesis and Structure of Crown Ether Complexes of Potassium Hexachlorodipalladate(II) and -diplatinate(II) K2[MCl4] (M ? Pd, Pt) reacts with an excess of crown ether 18-crown-6 in water to give the crown ether complexes of potassium hexachlorodipalladate(II) and -diplatinate(II) [K(18-cr-6)]2[M2Cl6] (M ? Pd, 1 ; M ? Pt, 3 ), respectively, and in methylene chloride to give those of potassium tetrachloropalladate(II) and -platinate(II) [K(18-cr-6)]2[MCl4] ( 1 ) (M ? Pd, 2 ; M ? Pt, 4 ), respectively. 1 - 4 are characterized by microanalysis, NMR (1H, 13C), and vibrational spectroscopy. The X-ray structure analyses of the isotypic complexes 1 (P21/c; a = 10,9678(8), b = 8,2991(7), c = 22,469(2) Å, β = 98,523(5)°; Z = 2) and 3 (P21/c; a = 10,934(3), b = 8.376(3), c = 22,410(5) Å, β = 98,77(3)°; Z = 2) reveal [M2Cl6]2? anions of nearly D2h symmetry and [K(18-cr-6)]+ cations, in which the distance of K+ to the mean plane of the crown ether defined by its six oxygen atoms amounts to 0,830(4) Å in 1 and 0,821(2) Å in 3 , respectively. There are tight contacts between cations and anions (d(K-Cl): 3,341(2)/3,260(2) Å ( 1 ); 3,348(4)/3,259(4) Å ( 3 )).  相似文献   

10.
Summary Platinum(II) and Palladium(II) complexes with 2-mercaptopyrimidine, 2-thiocytosine (4-aminopyrimidine 2-thione), and isocytosine (2-amino-4-hydroxy pyrimidine) were prepared and characterised by elemental analysis, conductivity data, i.r.,1H n.m.r. and13C n.M.r. spectral studies. 2-Mercaptopyrimidine and 2-thiocytosine are coordinated to the metal ion through N(3) and C2S, thus forming a four-membered chelate ring. Isocytosine acts as a monodentate ligand and coordinates to the metal ion through N(1). All the complexes are non-electrolytes.  相似文献   

11.
A new series of complexes is synthesized by template condensation of glyoxal and oxalyldihydrazide in methanolic medium in the presence of divalent cobalt, nickel, copper, zinc and cadmium salts forming complexes of the type: [M(C8H8N8O4)X2] where M = Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and X = Cl−1, Br−1, NO 3 −1 , OAc−1. The complexes have been characterized with the help of elemental analyses, conductance measurements, magnetic susceptibility measurements, electronic, n.m.r., infrared and far infrared spectral studies. On the basis of these studies, a six coordinate octahedral geometry for these complexes has been proposed. The biological activities of the metal complexes have been tested in vitro against a number of pathogenic bacteria to assess their inhibiting potential. Most of the compounds have been found to exhibit remarkable antibacterial activities.  相似文献   

12.
Carbamoyl and alkoxycarbonyl complexes of palladium(II) and platinum(II) of the type M(pnp)(CONHR)Cl (pnp = 2,6-bis(diphenylphosphinomethyl)pyridine; M Pd, R  C6H5, p-CH3C6H4, p-CH3OC6H4, C6H11, t-Bu; M  Pt, R  C6H5), Pd(pnp)[CON(Pr)2]Cl (Pr = propyl), M(pnp)(COOR)Cl (M  Pd, R  C6H5, CH3; M  Pt, R  CH3), Pd(pnp)(COOCH3)2 result from reaction of M(pnp)Cl2 with carbon monoxide and amines or alkoxides at room temperature and atmospheric pressure.The carbamoyl complexes react with bases to give urethane or diphenylurea depending upon the experimental conditions.  相似文献   

13.
New mixed-ligand complexes with empirical formulae M(4-bpy)L2·1.5H2O (M(II)=Mn, Co), Ni(4-bpy)2L2 and Cu(4-bpy) L2·H2O (where: 4-bpy=4,4'-bipyridine, L=CC L2HCOO-) have been isolated in pure state. The complexes have been characterized by elemental analysis, ir spectroscopy, conductivity (in methanol, dimethylformamide and dimethylsulfoxide solutions) and magnetic and x-ray diffraction measurements. The Mn(II) and Co(II) complexes are isostructural. The way of metal-ligand coordinations discussed. the ir spectra suggest that the carboxylate groups are bonded with metal(II) in the same way (Ni, Cu) or in different way (Mn, Co). The solubility in water is in the order of 19.40·10-3÷1.88·10-3ł mol dm-3ł. During heating the hydrate complexes lose all water in one step. The anhydrous complexes decompose to oxides via several intermediate compounds. A coupled TG-MS system was used to analyse the principal volatile products of obtained complexes. The principal volatile products of thermal decomposition of complexes in air are: H2O2 +, CO2 +, HCl+, Cl2 +, NO+ and other. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

14.
Tri(1‐cyclohepta‐2, 4, 6‐trienyl)phosphane, P(C7H7)3 ([P] when coordinated to a metal atom), was used to stabilize complexes of platinum(II) and palladium(II) with chelating dichalcogenolato ligands as [P]M(E∩E) [E = S, ∩ = CH2CH2, M = Pt ( 3a ); E = S, ∩ = 1, 2‐C6H4, M = Pt ( 5a ), Pd ( 6a ); E = S, ∩ = C(O)C(O), M = Pt ( 7a ), Pd ( 8a ); E = S, Se, ∩ = 1, 2‐C2(B10H10), M = Pt ( 9a, 9b ), Pd ( 10a, 10b ); E = S, ∩ = Fe2(CO)6, M = Pt ( 11a ), Pd ( 12a )]. Starting materials in all reactions were [P]MCl2 with M = Pt ( 1 ) and Pd ( 2 ). Attempts at the synthesis of [P]M(ER)2 with non‐chelating chalcogenolato ligands were not successful. All new complexes were characterized by multinuclear magnetic resonance spectroscopy in solution (1H, 13C, 31P, 77Se and 195Pt NMR), and the molecular structures of 5a and 12a were determined by X‐ray analysis. Both in the solid state and in solution the ligand [P] is linked to the metal atom by the P‐M bond and by η2‐C=C coordination of the central C=C bond of one of the C7H7 rings. In solution, intramolecular exchange between coordinated and non‐coordinated C7H7 rings is observed, the exchange process being markedly faster in the case of M = Pd than for M = Pt.  相似文献   

15.
Metal Pseudohalides. XL. Dicyanamido Metallates [M{N(CN)2}4]2? of Palladium(II) and Platinum(II) The synthesis of homologeous tetrakis-(dicyanamido) metallates(II), [M{N(CN)2}4]2? is reported. The coordination type of the ambivalent dicyanamide ligand is discussed on the basis of the i.r. and n.m.r. spectra of the new complexes.  相似文献   

16.
Complex formation of magnesium(II), manganese(II), nickel(II), copper(II) and lead(II) with S-carboxymethyl-L-cysteine in aqueous solution.The complex formation between Mg(II), Mn(II), Ni(II). Cu(II), Pb(II) ions and S-carboxy-methyl-l-cysteine (H2A) has been studied by measurement of pH at 25°C and constant ionic strength (1 M NaClO4). Although no interaction occurs with Mg(II), this work provides evidence for a variety of complexes: MnA; CuHA+; CuA; CuA22-; NiHA+; NiA; NiA22-; PbHA+; PbA et PbA(OH)-. The overall formation constants of all these species are computed and refined. The results allow the determination of the distribution of the complexes as a function of pH; some structural features of the metal complexes in solution are indicated.  相似文献   

17.
Investigation on the Alkylation of Bis-Stilbendithiolato Complexes of NiII, PdII, and PtII Alkylation reactions of co-ordinated ligands of the type of ethylene-bisthiol R2S2C22-proceed different depending on the substituents R. The neutral complexes isolated by a alkylation of the nickel bis-chelates (R = phenyl) according to Schrauzer and Rabinowitz and formulated by these authors as mixed ligand chelates of dithiolate and diether, were identified by us as complexes of the monoethers of the ligand. These nickel (II) complexes of the mono-ethers can not be alkylated further by alkyliodides. Oxidative coupling of two ligands yields disulfides which have been identified by mass spectroscopy thus indicating the original position of attack of the alkylating reagent. The formation of bis-monether complexes is reflected by the different charges on the S atoms of the model complex [Ni(CH3S2C2H2)(S2C2H2)]- obtained from EHT and CNDO calculations. Both possible stereo-isomers have been isolated of the bis-methylmonether complex of Pt(II). Trans-[M((CH3)(S2C2Ph2))2] (M = Ni(II), Pd(II)) form CH2Cl2 adducts. By treating the Ni-bis complexes of the monoalkylthioethers with iodine polyiodides are prepared. Binuclear Pd(II) complexes of composition [Pd2((R)(S2C2Ph2))2Cl2] could be prepared by metal exchange.  相似文献   

18.
Summary Rhodium(I), iridium(I), palladium(II) and platinum(II) complexes of the phosphinoamide ligands, Ph2PCH2CONHR (R = H, HDPA; Me, MDPA; Ph, PDPA) were prepared and characterized by using conductivity data, i.r., 1H and 31P(H) n.m.r. spectral data. Reaction of the ligands with MCl(PPh3)3 and MCl(CO)(PPh3)2 (M = Rh, Ir) in CH2Cl2 under reflux lead to the formation of MCl(PPh3)2 [Ph2PCH2C(O)NHR] and MCl(CO)(PPh3)[Ph2PCH2–C(O)HNR] respectively. The reaction of either K2MCl4 or cis-MCl2(PPh3)2 affords complexes of the type cis-MCl2[Ph2PCH2C(O)NHR]2 (M = Pd, Pt). A similar product results even from the reaction of phosphinoamides with cis-platin. Possible structures are proposed for the complexes based on their physicochemical data  相似文献   

19.
Complexes of composition L2MCl2 [M=Pt, R=H (I), Me (II), Ph (III)], and LMC12 [M=Pd, R=H (IV)] are prepared by reaction of 4,6-R2-2,5-diphenyl-1,3,2,5-dioxaboraphosphorinanes (L) with MCl2. Far-IR and31P NMR spectroscopy are used to demonstrate that I is cis whereas II and III are trans complexes in the solid. The conformational behavior of I is studied by31P and1H NMR. The asymmetric form of I exhibits anomalous stability.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2309–2312, October, 1991.  相似文献   

20.
Cationic palladium(II) and platinum(II) complexes with chelate ylides and neutral ligands of the type, [MCl (Y) (L)]+BPh4? (M  Pd or Pt; Y  bdep or bdmp*; L = 4-methylpyridine, 3,5-dimethylpyrazole, PPh3, PCy3, PMePh2, P(OMe)3, AsPh3 or SbPh3) and [M(bdep) (4-methylpyridine)2] (BPh4)2 (M = Pd or Pt) were prepared and characterized by means of infrared and 1H NMR spectra.  相似文献   

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