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1.
The preparation of monomeric complexes [MX( 1 )] is reported where M = Cu, Ag, Au; X = I, Cl, NO3, BF4 and 1 = 2,11-bis(diphenylphosphinomethyl)benzo[c]phenanthrene. The solution structure of the complexes is discussed on the basis of molecular weight, conductivity and NMR. measurements. In acetonitrile and nitromethane, the nitrate and fluoroborate complexes exist as ionic species [M( 1 )]+X? whereas the halo-complexes are present as equilibrium mixtures of ‘covalent’ and ‘ionic’ forms. All the complexes are associated in CH2Cl2-solutions. The values of 1J show that this association in [Ag(NO3) ( 1 )] and [Ag(BF4) ( 1 )] is best described in terms of ion-pairing while that for species [AgX( 1 )] (X = Cl, Br and I) is mainly ‘covalent’ in nature. Evidence is presented for the formation of the complex ion [Ag(CH3CN)n( 1 )]+ in acetonitrile solution.  相似文献   

2.
The preparation of the bidentate ligand 2, 11-bis(diphenylarsinomethyl)benzo-[c]-phenanthrene ( 1 ) is described. This ligand reacts with appropriate substrates to give mononuclear square planar complexes of type [MX2( 1 )] (M = Pd, Pt; X = Cl, Br, I) and [M′Cl(CO)( 1 )] (M′ = Rh, Ir) in which ligand 1 spans trans-positions. This is confirmed by the crystal structure of [PtCl2( 1 )]. 1H-NMR. spectra of the complexes are discussed and compared with those of model compounds trans-[MCl2( 12 )2] (M = Pd, Pt) and [M'Cl(CO)( 12 )2] (M′ = Rh, Ir; 12 = AsBzPh2).  相似文献   

3.
The five-coordinate mononuclear complexes [M(CO)3( 1 )] (M = Fe, Ru; ( 1 ) = 2,11-bis(diphenylphosphinomethyl)benzo[c]phenanthrene) have been prepared and assigned trigonal bipyramidal structures with apical phosphorus atoms from IR. and NMR. data.  相似文献   

4.
The bidentate ligand 2,11-bis(diphenylphosphinomethyl)benzo[c]phenanthrene ( 1 ) was synthesized from 2,11-dimethyl-benzo[c]phenanthrene ( 3 ) via the corresponding bromomethyl derivative 9. 3 was obtained from the cyclization with boron trifluoride etherate of 1,1-di-(p-methylphenethyl)-epoxyethane ( 7 ), which was prepared from 1,5-di(p-tolyl)-pentan-3-one ( 6 ).  相似文献   

5.
The complexes trans-[PtXY( 2 ] (X = H or Me; Y = OMe, OCHO, CO2H, and BH4; 2 = 2,11-bis{bis[3-(trifluoromethyl)phenyl]phosphinomethyl}benzo[c]phenanthrene) were prepared, and their decompositions to trans[PtHX( 2 )] were studied. Some binuclear hydrido-bridged complexes, e.g.[( 2 )HPt(μ-H)PtH( 2 )]+, were also obtained. The preparation of complexes trans-[PtHX( 28 )2] (X = H or Me, 28 = bis[3-(trifluoromethyl)phenyl]benzylphosphine) is also reported. The X-ray crystal structure of trans-[PtHCl 1 )] ( 1 = 2,11-bis(diphenylphosphinomethyl)benzo[c]phenanthrene) was carried out.  相似文献   

6.
The preparation of the nucleophile trans-[RuCl(NO)( 1 )], where 1 is the bidentate ligand Ph2PCH2C18CH2PPh2, and of the five-coordinate species [RuCl(CO)(NO)( 1 )], [RuCl(CO)(NO)(Ph2PCH2Ph)2] and [RuCl(NO)( 2 )( 1 )] are reported. The crystal structure of [RuCl(CO)(NO)( 1 )] shows that the coordination around the metal atom is distorted trigonal bipyramidal with the phosphorus atoms in axial positions. The Ru? N? O bond angle is 142.8°. 1H- and 31P-NMR. and \documentclass{article}\pagestyle{empty}\begin{document}$ \tilde \nu $\end{document}NO IR.-data for the above complexes are reported and related to the coordination geometry.  相似文献   

7.
The 31P{1H}-NMR characteristics of the complexes [HgX2( 1 )] and [HgX2-(PPh2Bz)2] (X = NO3, Cl, Br, I, SCN, CN) and the solid state structures of the complexes [HgCl2( 1 )] and [HgI2( 1 )] ( 1 = 2,11-bis (diphenylphosphinomethyl)benzo-[c]phenanthrene) have been determined. The 1J(199Hg, 31P) values increase in the order CN < I < SCN < Br < Cl < NO3. The two molecular structures show a distorted tetrahedral geometry about mercury. Pertinent bond lengths and bond angles from the X-ray analysis are as follows: Hg? P = 2.485(7) Å and 2.509 (8) Å, Hg? Cl = 2.525 (8) Å and 2.505 (10) Å, P? Hg? P = 125.6(3)°, Cl? Hg? Cl = 97.0(3)° for [HgCl2( 1 )] and Hg? P = 2.491 (10) Å and 2.500(11) Å, Hg? I = 2.858(5) Å and 2.832(3) Å, P? Hg? P = 146.0(4)°, I? Hg? I = 116.9(1)° for [HgI2( 1 )]. The equation, derived previously, relating 1J(199Hg, 31P) and the angles P? Hg? P and X? Hg? X is shown to be valid for 1 .  相似文献   

8.
Complexes [MX2(1)] (M = Ni, Pd and Pt; X=Cl and NCS; 1 = 2,11-bis(dialkyl-[or diaryl]phosphinomethyl)benzo[c]phenanthrene; alkyl = cyclohexyl t-butyl; aryl = m-tolyl, p-anisyl and m-CF3 C6H4) have been synthesized. An NMR. study of the t-butyl complexes provides evidence for a “fan-like” motion of the benzo[c]phenanthrene moiety over the plane of the complex.  相似文献   

9.
采用密度泛函方法(B3LYP)优化了MX2(AsH3)2[M=Pd;X=Cl(1),Br(2),I(3)和M=Pt;X=Cl(4),Br(5),I(6)]的基态结构,得到的几何参数与实验结果符合.以基态几何为基础,将TD-DFT方法用于计算标题配合物的电子吸收光谱.研究结果表明,金属的dx2-y2与配体所组成的反键轨道为LUMO轨道,从而该类配合物具有d-d跃迁属性的吸收带;在多数跃迁过程中,配体也有较大的贡献.  相似文献   

10.
The complex [IrCl3(CO)( 1 )]( 4,1 =2,11-bis (diphenylphosphinomethyl)benzo[c]phenanthrene) has been prepared by CuCl2-oxidation of [IrCl(CO)( 1 )]( 2a ). It is shown that the chlorine oxidation of 2a gives a mixture of products whose composition depends on the reaction conditions. The X-ray crystal structures of 2a and 4 have been determined. The small conformational differences observed for the trans-spanning ligand 1 in the two complexes are likely to be caused by the difference in Ir-P bond lengths in square planar 2a and octahedral 4 (2.310(4) and 2.411(3) Å, respectively).  相似文献   

11.
Kinetic and spectroscopic studies of the reactions of cyclohexylamine with the complexes [MX2(1,5-cyclooctadiene)] (I) (M = Pd; X = Cl, Br; M = Pt, X = Br) in acetone reveal the rate law, kobs = K1k2[amine]2, for the rapid sequence
For X = Br, the palladium(II) complex is ca. 70 times more reactive than its platinum(II) analogue. This is the first quantitative comparison reported to date for nucleophilic attack upon olefins coordinated to PdII and PtII centres. The reactivity order PdII ⪢ PtII may arise from the higher ionization potential of Pd2+ compared to Pt2+, which makes PdII a less effective back-π-bonder. Replacing the bromo ligands in [PdBr2(1,5-COD)] by chloro ligands lowers the rate of formation of III by a factor of 8.  相似文献   

12.
Preparation and Characterization of [Pt(mal)2]2? and trans-[Pt(mal)2X2]2? (X = Cl, Br, I, SCN) By twofold treatment of K2[PtCl4] with potassium hydrogen malonate in a queous solution the yellow K2[Pt(mal)2] · H2O is obtained. After extraction with tetrabutylammonium ions into dichloromethane by oxidative addition at ?90°C the PtIV complexes [Pt(mal)2X2]2?, X = Cl, Br, I, SCN, are formed. The SCN ligands are coordinated to Pt via S. The IR and Raman spectra are discussed and assigned.  相似文献   

13.
The 1H-NMR spectra of the complexes trans-[PtX2(C2H4)(Him)] (X = Cl or Br, Him = imidazole) are discussed. Variable temperature spectra are used to monitor the exchange processes which occur in acetone-d6 solution. It is found, contrary to previous work, that intermolecular exchange occurs for both the chloro- and bromo- complexes. In addition, it is also found that changing the solvent has a marked effect on the rate of exchange. Using an iterative simulation program and assuming intermolecular exchange, the rate constants for the exchange process are determined by band shape analysis, and the enthalpy and entropy of activation are calculated.  相似文献   

14.
The complex [Pd(2-Phpy)(μ-Cl)]2 reacts with pyridines (L=pyridine, α-picoline and γ-picoline), amines (L=isopropylamine, tert-butylamine) and ammonia to form the corresponding ortho-palladatedderivatives [Pd(2-Phpy)ClL]. The compounds have been characterized by C, H and Nanalyses and spectroscopic methods (IR and 1H and 13C NMR).TG, DTG and DSC studies of the complexes were carried out in dynamic nitrogen atmosphere. From DSC analyses the heats of decomposition were calculated. The kinetics ofthe first step of thermal decomposition were evaluated from TG data by isothermal methods for L=pyridine and isopropylamine. The activation energies obtained are in the range 90–100 kJ mol-1. The best fitting for data was observed for R2 and A1.5 kinetic models. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

15.
It is shown that ligand 1 , designed to span trans-positions, under appropriate conditions also gives cis-mononuclear complexes of platinum (II). The structure of cis-[PtCl2 (1) ] (2) has been determined by single-crystal X-ray diffraction. The major distortion from square planar coordination is the P-Pt-P angle of 104.8°. Values of valence angles within the bidentate ligand indicate that this part of the molecule is very strained. Two phenyl groups, one on each phosphorus, lie almost parallel to each other separated by ca. 3.2–3.3 Å. The 1H-NMR. data for this compound show that the π-phenyl interactions observed in the solid state occur also in solution. The preparation and NMR.-spectroscopic properties of trans- and cis-[PtH(PPh3) (1) ] [BF4] are reported.  相似文献   

16.
The i.r. spectra (4000-80 cm−1) of the newly-reported complexes cis- and trans-[Pt(pz)2X2] (pz = pyrazine; X = Cl, Br, I, NO2) are discussed. Assignments for internal ligand modes are based on the effects of ligand deuteration. Assignments of metal—ligand modes are based on the effects of halide substitution and pyrazine labelling.  相似文献   

17.
Preparation of trans-[Pt(ox)2X2]2? (X = Cl, Br, I, SCN, OH) by Oxidative Addition to [Pt(ox)2]2? in Organic Solvents After extraction of [Pt(ox)2]2? with long-chain alkyl-ammonium ions into organic solvents the new PtIV complexes trans-[Pt(ox)2X2]2?, X = Cl, Br, I, SCN, OH, are formed directly by oxidative addition. In nonpolar solvents the bulky organic cations prevent the formation of compounds with columnar structure which by partial oxidation in aqueous solution are formed immediately. The IR and Ra spectra of the stable anhydrous (TBA) salts are assigned according to point group D2h. A characteristical dependence of the C?O, C? O, and Pt? O stretching modes in response to the oxidation state of the central ion is observed. There is vibrational fine structure in the absorption spectrum of [Pt(ox)2]2? measured at 10 K with long progressions by coupling of d—d transitions with vs(Pt? O) and vs(C?O). The characteristical feature in the UV/VIS spectra of the PtIV complexes is caused by intensive π(O, X) ← eg(Pt) CT transitions.  相似文献   

18.
Dynamic NMR experiments on trans-[Pt(Cl)(PHCy2)2[P(X)Cy2]]z where X is a lone pair (1, z = 0), H (2, z = +1), S (3, z = 0), or O (4, z = 0) show that the rotation around the P(X)-Pt bond is hindered for all molecules studied, with deltaG++ ranging from 8.2 to 11.0 kcal/mol. The highest value of the series was calculated for trans-[Pt(Cl)(PHCy2)2[P(O)Cy2]] (4) where intramolecular P=O...H-P interactions act as a molecular brake at room temperature. Single-crystal X-ray diffraction confirms the presence of both intra and intermolecular P=O...H interactions in solid 4. In the case of [Pt(Cl)(PHCy2)3]Cl, multinuclear NMR analysis indicates the presence of a P-H...Cl- interaction in aromatic or halogenated solvents which could have also a minor effect on the rotational barrier around the P(X)-Pt bond.  相似文献   

19.
Mixed salts of noble metals with the general formula [Pd(NH3)4][MA6], where M = Re, Os, Ir, Pt;A = Cl,Br, and Ag2[Pd(NO2)4]-Ag1-xNaxNO2 (x> 0.3) have been synthesized and studied by X-ray diffractometry. It was found that the former are isostructural to each other and the latter are isostructural to Na2[Pd(NO2)4j-NaNO2. The structural motif of these compounds was established and metal-metal distances were estimated by the cation sublattice method In all cases, metal atoms form common cation sublattices with lattice parameters between 4.5 and 6.3 Å. An original approach to revealing common sublattices in crystal structures where the fragments differ considerably in weight is described.  相似文献   

20.
The structures of [RhCl(CO) ( 1 )] and [PdCl2 ( 1 )], where 1 is the bidentate ligand (C6H5)2P·CH2·C18H10· CH2·P(C6H5)2, have been determined from threedimensional X-ray counter data collected on single crystals of the C6H5·CN solvates. The two compounds are isomorphous and crystallize in the triclinic system, space group P 1 , Z = 2: a = 14.580 (8), b = 13.029 (10), c = 11.909 (6) Å, α = 106.33 (5), β = 100.47 (4), γ = 95.73 (5)° for the rhodium complex; a = 14.361 (5), b = 13.044 (7), c = 11.897 (4) Å, α = 105.97 (4), β = 100.27 (3), γ = 94.76 (4)°, for the palladium complex. In both complexes the metal atom is four-coordinate with slightly distorted square-planar configuration. In both cases the ligand 1 spans trans positions with M-P bond lengths in the ranges of the literature data. Also the other bond distances fall in regular ranges. Ligand 1 has almost the same conformation in both complexes and is characterized by a strong out-of-plane deformation of the benzophenanthrene system as a consequence of severe overcrowding.  相似文献   

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