共查询到20条相似文献,搜索用时 15 毫秒
1.
The synthesis and structural characterization of palladium complexes 1-3 incorporating H-spirophosphorane HP(OCMe2CMe2O)2 and H-phosphonate congener HP(O)(OCMe2CMe2O) ligands are reported. The chemical composition of the complexes [PdCl(μ-Cl){P(OCMe2CMe2O)OCMe2CMe2OH}]2 (1), [Pd{P(O)(OCMe2CMe2O)}2]n (2), and [Pd(μ-Cl){P(OCMe2CMe2O)OH}{P(OCMe2CMe2O)O}]2 (3) was established by means of NMR, IR, ESI-MS spectroscopic methods. The relative stereochemistry of 1 and 3 was unambiguously determined by single X-ray diffraction studies. It was proved that complexes 1-3, and complex [PdCl2P(OCH2CMe2NH)OCH2CMe2NH2] (4) previously described in the literature, are very efficient catalysts for the Heck cross-coupling of bromobenzene with n-butyl acrylate. Moreover, they were also found to be effective catalysts in the stereoselective synthesis of trans-stilbenes. 相似文献
2.
The reaction of the hydrospirophosphorane HP(OCMe2CMe2O)2 ligand or the five-membered cyclic hydrogen phosphonate HP(O)(OCMe2CMe2O) ligand with the ReOCl3(OPPh3)(SMe2) precursor under controlled reaction conditions led to the isolation of dimeric oxo-rhenium(V) complexes containing P(O)(OCMe2CMe2O)− moieties, represented by [ReOCl2{μ-OP(OCMe2CMe2O)}3ReOCl(OPPh3)] (1) and [ReOCl2(SMe2){μ-OP(OCMe2CMe2O)}]2 (2). The chemical composition of these complexes was established by means of NMR, IR spectroscopic methods, and based on analytical data. The relative stereochemistry of 1 and 2 was unambiguously determined by single X-ray diffraction studies. The crystal structure of 1 comprises two crystallographically independent molecules in an asymmetric unit and co-crystallised molecules of both dichloromethane and acetonitrile. Two different six-coordinated monomeric subunits, ReOCl2 and ReOCl(OPPh3), connected by three phosphonate bridges, build up the dinuclear complex 1. It exhibits an uncommon feature, a cis disposition of the triphenylphosphine oxide molecule relative to the terminal ReO bond. The crystal structure of 2 includes four molecules, in which two equivalent rhenium subunits ReOCl2(SMe2) are linked by two P(O)(OCMe2CMe2O)− bridges. 相似文献
3.
《Inorganica chimica acta》1986,116(1):21-30
A study of the reactions of Mo(CO)5(P(OCH2- CMe2CH20)X) (X = C1, Br) with a variety of nucleophiles of the type HER (E = NH, O, S; R = H, alkyl, aryl) is reported. The mechanism of these reactions is shown to be SN2, and the significantly slower rates of reactions of n-propylamine with the above complexes relative to the rate of reaction of n-propylamine with Mo(CO)5(Ph2PC1) is discussed.The 13C, 17O, 31P and 95Mo NMR data and infrared data for these complexes are presented. Good correlations between chemical shifts of the cis and trans CO13C and trans CO170 NMR resonances, CO infrared stretching force constants and the magnitudes of 1JMop and 2JPC (trans CO) are observed and the reasons for these correlations are discussed.The correlations between the chemical shifts of NMR-active nuclei in the Mo(CO)5(P(OCH2CMe2- CH2O)ER) complexes with the chemical shifts of similar nuclei in the Mo(CO)5(Ph2PER) complexes fange from excellent to very poor. This indicates that the effects of-the P-substituents on the chemical shifts of the NMR-active nuclei in these complexes are not additive. 相似文献
4.
《Inorganica chimica acta》1986,120(1):25-32
A study of the reactions of M(CO)5(P(OCH2CH2CH(Me)O)Cl) (M=Cr, Mo) with a variety of nucleophiles of the type HER (E=NH, O, S; R=H, alkyl, aryl) is reported. The 13C, 31P and 95Mo NMR and IR spectral data for the M(CO)5(P(OCH2CH2CH(Me)O)ER) complexes is presented and compared to that previously reported for some Mo(CO)5(P(OCH2CMe2CH2O)ER) complexes. This comparison provides insight into the manner in which variations in the metal and in the substitution on the 1,3,2-dioxaphosphorinane ring affect the electron density distribution within these complexes.The results from a study of the rates of chloride substitution by n-propylamine in the M(CO)s(P(OCH2CH2CH(Me)O)Cl) complexes are also presented. These rates are compared with those previously reported for chloride substitution by n-propylamine in the Mo(CO)5(P(OCH2CMe2CH2O)Cl) and Mo(CO)5(Ph2PCl) complexes. These comparisons, in conjunction with the NMR and IR studies, suggest that both the position of the Me groups on the phosphorinane ring and the amount of electron density on the P have significant effects upon the rate of chloride substitution in these complexes. 相似文献
5.
A non-stoichiometric material [Na4(5′-IMP)2·15H2O]0.2[Na2(Pt(5′-IMP)2 (trimethylenediamine))·13.5H2O]0.8 has been prepared and investigated by single-crystal X-ray methods and 1H and 13C nmr spectroscopy. The compound is isomorphous with the monosodium and disodium salts of 5′-IMP and two Pt(II)-5′-IMP compounds previously reported to be non-stoichiometric. However, the structural changes in the packing motif of the 5′-IMP molecules induced on Pt(II) coordination are uniform only if the 5′-IMP complex containing (NH3)2Pt(II) is stoichiometric. Preliminary studies on the latter complex, synthesized in our laboratories, demonstrate that the complex is indeed stoichiometric. 相似文献
6.
In an attempt to prepared tetrakis(tert-butoxy)uranium(IV) a trinuclear oxo-alkoxide of uranium(IV) was obtained instead. The compound has the formula U3O[(CH3)3CO]10 and it crystallizes in the hexagonal space group P63mc with a = b = 18.256(4) Å, c = 10.013(2) Å, Z = 2. The trinuclear unit is strikingly reminiscent of that in Mo3O(OCH2CMe3)10. In contrast to the molybdenum compound where there is metal-metal bonding, the U?U distance of 3.574(1) Å indicates a non-bonded interaction. 相似文献
7.
Douglas D. Wick 《Inorganica chimica acta》2009,362(12):4416-5792
Treatment of Tp′Rh(PMe3)Cl2 and Tp′Rh(CNCH2CMe3)Cl2 with Cp2ZrH2 produces Tp′Rh(PMe3)H2 and Tp′Rh(CNCH2CMe3)H2, respectively, in excellent yield. Photolysis of benzene solutions of each dihydride complex generates hydrogen and the fragment [Tp′Rh(L)] which inserts into the solvent C-H bond. The phosphine dihydride has also been shown to be a catalyst for the hydrogenation of biphenylene, showing a capability to cleave C-C bonds. Reductive elimination of benzene from Tp′Rh(PMe3)PhH is nearly 250 times slower than from Cp*Rh(PMe3)PhH. 相似文献
8.
The initial reaction mechanisms for depositing ZrO2 thin films using ansa-metallocene zirconium (Cp2CMe2)ZrMe2 precursor were studied by density functional theory (DFT) calculations. The (Cp2CMe2)ZrMe2 precursor could be absorbed on the hydroxylated Si(1 0 0) surface via physisorption. Possible reaction pathways of (Cp2CMe2)ZrMe2 were proposed. For each reaction, the activation energies and reaction energies were compared, and stationary points along the reaction pathways were shown. In addition, the influence of dispersion effects on the reactions was evaluated by non-local dispersion corrected DFT calculations. 相似文献
9.
Reaction of cis-(NH3)2Pt(1-MeU)2 (1-MeU = 1- methyluracil anion, C5H5N2O2) with ZnSO4·7H2O leads to the formation of a dinuclear complex of composition [(NH3)2Pt(C5H5N2O2)2Zn(H2O)3]SO4· 2H2O. The compound crystallizes in space group P21/c with a = 10.534(1), b = 17.933(2), c = 11.490(1) Å, β=94.61(1)°, Z=4. The structure was refined to R=0.043 and Rw=0.061. In this compound, Pt is coordinated through N3 to the 1-MeU ligand, while Zn is bound through the two O4 oxygens and completes its distorted square-pyramidal coordination sphere by three aqua ligands. The positions of the two metals relative to their basal donor atoms and the shortness of the PtZn separation (2.760(1) Å) suggest a bonding interaction between the two metals. Using 1H NMR spectroscopy, a formation constant of ca. 114 1 mol?1 for the Pt, Zn complex has been estimated. 相似文献
10.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):557-564
Four complexes [Pd(L)(bipy)Cl]·4H2O (1), [Pd(L)(phen)Cl]·4H2O (2), [Pt(L)(bipy)Cl]·4H2O (3), and [Pt(L)(phen)Cl]·4H2O (4), where L = quinolinic acid, bipy = 2,2’-bipyridyl, and phen = 1,10-phenanthroline, have been synthesized and characterized using IR, 1H NMR, elemental analysis, and single-crystal X-ray diffractometry. The binding of the complexes to FS-DNA was investigated by electronic absorption titration and fluorescence spectroscopy. The results indicate that the complexes bind to FS-DNA in an intercalative mode and the intrinsic binding constants K of the title complexes with FS-DNA are about 3.5?×?104 M?1, 3.9?×?104 M?1, 6.1?×?104 M?1, and 1.4?×?105 M?1, respectively. Also, the four complexes bind to DNA with different binding affinities, in descending order: complex 4, complex 3, complex 2, complex 1. Gel electrophoresis assay demonstrated the ability of the Pt(II) complexes to cleave pBR322 plasmid DNA. 相似文献
11.
David M.L. Goodgame Paul B. Hayman Richard T. Riley David J. Williams 《Inorganica chimica acta》1984,91(2):89-93
The preparations are reported of cis[Pt(caffeine)2Cl2]·0.4H2O, Pd(caffeine)2Cl2, the methanol adduct of the previously known compound K[Pt(caffeine)Cl3], and Pt(caffeine)(cytidine)Cl2. Crystals of [Pt(caffeine)2Cl2]·0.4H2O are tetragonal P42/n with a = 13.156(2) 0?, c = 12.734(2) 0?, Z = 4. The structure was refined on 945 reflections to R = 0.025. The molecule is cis with a crystallographic two-fold axis bisecting the ClPtCl and NPtN angles. The Pt is square planar with PtN and PtCl bonds of 2.029(5) Å and 2.271(2) Å respectively. There is a 5.4° dihedral angle between the imidazole and pyrimidine rings, and the imidazole ring is rotated away from the coordination plane by 86.4°. Symmetry related caffeine units pack parallel to each other with an inter-ring separation of 3.45 Å. 相似文献
12.
Dichloroplatinum complexes [PtCl2L2] (L2 = cod, dppp) react with 1,2-C6H4E2 (E = O, S) in the presence of a base to produce mononuclear complexes. The diene was not readily displaced from [Pt(E2C6H4-EE)(cod)]. A second approach to complexes containing dianionic chelating ligands involved [Pt(acac)2] as precursor. Reaction with dppp and oxalic acid gave [Pt(C2O4)(dppp)], whereas the analogous reaction with Ph2PCCPPh2 produced the bimetallic complex [Pt(C2O4-OO)(μ-Ph2PCCPPh2)]2. Similar reactions with 1,2-C6H4E2 (E = O, S) also gave bimetallic products. The structures of [Pt(C2O4)(dppp)] and [Pt(C2O4-OO)(μ-Ph2PCCPPh2)]2 have been determined by X-ray crystallography. 相似文献
13.
A novel synthetic method for the synthesis of the complexes cis-Pt(amine)2R(COO)2 is compared to two other methods involving the use of either barium dicarboxylate or sodium carboxylate. Pt(II) compounds with monodentate and bidentate amines were studied. The reaction involves the use of a silver dicarboxylato complex, which is the intermediate in the new synthetic procedure. The crystal structure of the silver intermediate with the ligand 1,1-cyclobutanedicarboxylate (1,1-CBDCA) was determined by X-ray diffraction. The crystal Ag2(1,1-CBDCA) has a very interesting 3-D extended structure. The complexes cis-Pt(amine)2R(COO)2 were studied in solution by multinuclear (1H, 13C and 195Pt) magnetic resonance spectroscopy, but the solubilities are very low. D2O was found to be the best solvent. In 195Pt NMR, the complexes containing bidentate amines forming five-membered chelates were observed at higher fields than those containing monodentate amines. The resonances of the NH3 compounds were also found at lower fields than the primary amine complexes. All the dicarboxylato ligands form six-membered chelates except 1,2-CBDCA, whose Pt(II) compounds were observed at lower fields than the others. The crystal structures of Pt(en)(1,1-CBDCA), Pt(Meen)(1,1-CBDCA) and Pt(en)(benzylmalonato) were confirmed by X-ray diffraction methods. Several compounds are disordered. The crystals are stabilized by intermolecular hydrogen bonds between the -NH2 groups and the carboxylato O atoms. 相似文献
14.
Complexes of Co(II), Ni(lI), Cu(II), Zn(II) and Pt(II) with 1-formylisoquinoline thiosemicarbazone (1-iqtsc-H) were prepared and characterized by elemental analyses, conductance measurement and spectral studies. On the basis of these studies a distorted octahedral structure for [Co(1-iqtsc)2]·2H2O, a distorted trigonal-bipyramidal structure for [Ni- (1-iqtsc-H)Cl2], [Cu(1-iqtsc-H)Cl2] and [Zn(1-iqtsc- H)(OAc)2]·H2O and a square-planar structure for [Pt(1-iqtsc)Cl] are suggested. All these metal(II) complexes were screened for their antitumour activity in the P388 lymphocytic leukaemia test system in mice. Except for Pt(Il), the complexes were found to possess significant activity; the Ni(II) complex showed a T/C value of 161 at the optimum dosage. 相似文献
15.
We have reacted [Pt(dien)Cl]Cl, [Pt(en)(D2O)2]2+, and [Pt(Me4en)(D2O)2]2+ [Me4en = N,N,N′,N′-tetramethylethylenediamine] with selenomethionine (SeMet). When [Pt(dien)Cl]Cl is reacted with SeMet, [Pt(dien)(SeMet-Se)]2+ is formed; two Se-CH3 resonances are observed due to the different chiralities at the Se atom upon platination. In a reaction of [Pt(dien)Cl]Cl with an equimolar mixture of SeMet and Met, the SeMet product forms more quickly though a slow equilibrium with approximately equal amounts of both products is reached. [Pt(Me4en)(D2O)2]2+ reacts with SeMet to form [Pt(Me4en)(SeMet-Se)(D2O)]2+ initially but forms [Pt(Me4en)(SeMet-Se,N)]+ ultimately. One stereoisomer of the chelate, assigned to the R chirality at the Se atom, dominates within the first few minutes of reaction. [Pt(en)(D2O)2]2+ forms a variety of products depending on reaction stoichiometry; when one equivalent or less of SeMet is added, the dominant product is [Pt(en)(SeMet-Se,N)]+. In the presence of excess SeMet, [Pt(en)(SeMet-Se)2]2+ is the dominant initially, but displacement of the en ligand occurs leading to [Pt(SeMet-Se,N)2] as the eventual product. Displacement of the en ligand from [Pt(en)(SeMet-Se,N)]+ does not occur. In reactions of K2PtCl4 with two equivalents of SeMet, [Pt(SeMet-Se,N)2] is formed, and three sets of resonances are observed due to different chiralities at the Se atoms. Only the cis geometric isomers are observed by 1H and 195Pt NMR spectroscopy. 相似文献
16.
《Inorganica chimica acta》1988,153(1):31-38
A complex containing a protonated and N3-platinated cytosine (C), [CH][Cl3Pt(C)] (1a) has been prepared, converted into its K[Cl3Pt(C)] (1b) and NH4[Cl3]Pt(C)]·H2O (1c) analogs, and structurally characterized (X-ray, Raman, NMR). Reaction of 1b with L = 1-methylcytosine and with L = Me2SO gave the neutral mixed-ligand complexes cis-Cl2Pt(C)L. Excess NH3 was used to convert the anion of 1b into the cation [(NH3)3Pt(C)]2+ (3a). The pKa of the N(1)H proton in 3a is 9.4, as determined by UV spectroscopy. The N(1)H is displaced by Pt(II) electrophiles even at neutral pH to give N3,N1-diplatinated cytosinato complexes, as shown by 1H NMR (3J coupling or 195Pt at N(1) with H6, 29 Hz, and 4J coupling of 195Pt at N(3) with H5, 14Hz). The results of the X-ray structure determination of 1a (R = 0.031, Rw = 0.034) are of relevance in that they permit a direct comparison of the effect of a proton as opposed to that of a Pt electrophile on the nucleobase geometry. Moreover, the expected decrease in CO(2) bond length as a consequence of Pt binding is observed. 相似文献
17.
Complexes of the types cis- and trans-Pt(amine)2I2 containing cyclic amines were synthesized and studied mainly by IR and multinuclear NMR spectroscopies. The compounds were converted to cis- and trans-Pt(amine)2(NO3)2, which were also investigated. The hydrolysis and the aquation reactions of the latter compounds were then studied in D2O in different conditions of pH. In acidic medium, the aqueous product is [Pt(amine)2(D2O)2]2+ and for a few amines, [Pt(amine)2(D2O)(NO3)]+ was detected. In basic pH, the main product is Pt(amine)2(OD)2 and Pt(amine)2(OD)(NO3) was detected for several compounds. In neutral pH, the cis isomers form between two and four species in fresh solutions. The most shielded species in 195Pt NMR is the monoaqua-monohydroxo complex cis-[Pt(amine)2(D2O)(OD)]+ and the less shielded compound is the dihydroxo-bridged dimer [Pt(amine)2(μ-OD)2Pt(amine)2]2+, which were observed for all the compounds. For a few amines, the monohydroxo-bridged dimer [Pt(D2O)(amine)2(μ-OD)Pt(OD)(amine)2]2+ was detected and for cyclohexylamine, a fourth signal was assigned to a cyclic hydroxo-bridged trimer [(Pt(amine)2(μ-OD))3]3+. 195Pt NMR spectroscopy has shown that the concentration of the monomer decreases with time, while the concentration of the dimers increases. Only one product was observed for the trans isomers in neutral pH. The signal was assigned to the monoaqua-monohydroxo species trans-[Pt(amine)2(D2O)(OD)]+. The 13C and 1H NMR spectra of most of the complexes were measured. All the coupling constants 2,3J(195Pt-1H) and 2,3J(195Pt-13C) are larger in the cis compounds than in the trans isomers. 相似文献
18.
Fernande D. Rochon Robert Melanson Jean-Pierre Macquet Francine Belanger-Gariepy Andre L. Beauchamp 《Inorganica chimica acta》1985,108(1):17-21
The structure of the complex [Pt(trans-1,2-di- aminocyclohexane) (acetate)2]·H2O has been determined by X-ray diffraction. This racemic compound is orthorhombic, space group Aba2, a = 20.813(9), b = 7.926(5), c = 17.296(8) Å, Z = 8. The structure was refined on 1214 nonzero Cu Kα reflections to R = 0.028. The square planar environment of Pt includes the amino groups of the diamine in cis positions and oxygens from two monodentate acetates. The PtN and PtO distances average 2.00(3) and 2.02(3) Å, respectively. The bite of the diamine ligand imposes a NPtN angle of 85(1)°, whereas the small OPtO angle of 85(1)° probably results from packing effects. The average plane through the puckered cyclohexyl ring makes an angle of 19° with the PtN2O2 plane. The molecules are stacked by pairs along the b axis. The two molecules of each pair are 180° apart about the stacking axis, and form altogether four NH···O hydrogen bonds. 相似文献
19.
Lucilene D. Mello Emerson S. Ribeiro Lauro T. Kubota Sofi K. C. Elmroth Regina M. S. Pereira 《Biometals》2009,22(2):385-392
The interaction of Pt(II)(dppf)-complex, namely [Pt(dppf)(H2O)2]2+ with DNA was investigated by DPV and 1H-NMR techniques. The results showed that the interaction process has been characterized by changes in the electrochemical
parameters of both compounds and the formation of a new anodic current peak close to the anodic current peak of the [Pt(dppf)(H2O)2]2+. In addition, the 1H-NMR spectra show that the coordination of Pt(II)(dppf)-complex to dsDNA occurs via N(7) of guanine. Others parameters like
pH and ionic strength that affect the interaction process were also investigated. 相似文献
20.
The reaction of xanthosine-5′'-monophosphate disodium salt (5′-XMPNa2) with Pt(II), Cu(II) and Mg(II) ions produced compounds of the type cis- and trans-Pt(NH3)2(XMPNa2)nCl2·xH2O, where n = 1 or 2; Pt(XMPNa2)nCl2·xH2O, where n = 1-4, x = 1,4 & 6; Cu(XMP)·6H2O and Mg(XMP)·xH2O, where x = 9 or 4. In the complexes synthesized here at neutral pH values, the nucleotide binds through the N7-atom of the purine ring system, whereas for Cu(II) and Mg(II) compounds obtained at pH = 4 a direct metal-phosphate interaction as well as Nτ bonding is proposed. 相似文献