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1.
1INTRODUCTIONTherehasbeenconsiderableattentionfocusedonthestudyofpalladiumcomplexinorganicsynthesis,catalyticprocesses,chemicalreactivity,spectroscopyandstructuralanalysisandfunctionalmaterials[1].Manypalladacycleshavebeenappliedinthepreparationofliquid-crystallinecomplexes[2],andsomeofthemshowantitumoractivity.Theincreasingimportanceofsuchcyclo-organometalliccomplexleadsustoinvestigatethecyclicPdcomplexeswithenhancedchemicalandthermalstability,fromwhichdetailedspectroscopicandstructuralc…  相似文献   

2.
<正> [K(C_12H_24O_6)]_2Pd(SCN)_4(H_2O),MT=963.59,monoclinic, P21/n,a= 11. 075(1),b= 12. 231(1),c= 15. 863(2) A ,β=93. 25(1)°,V=2145. 3A3,Z=2, Dc=1. 492gcm-3,λ(MoKa) = 0. 71073A μ=8. 64cm-1,F(000) = 996,final R=0. 045 for 1835 observable reflections. The Pd2+ ion coordinates with four S atoms from SCN- groups forming a regular square planar configuration. The K+ ion is surrounded by six ether oxygen atoms,one O atom from water molecule coordinated to two K+ions and one N atom from SCN- group to form a distorted hexagonal bipyramid. Two K atoms are linked with one Pd atom by two bridging SCN- groups forming a chain molecular array in the crystal.  相似文献   

3.
A novel Pd(II) Benzo-15-crown-5 complex [Na(B15C5)]2[Pd(SCN)4] has been isolated and characterized by IR and X-ray diffraction analysis.The crystal structure belongs to monoclinic,space group P21/n with cell dimensions,a=1.0164(6),b=1.3743(3),c=1.4987(7) nm,b=95.248(6)o ,V=2.0847nm3,Z=2,F(000)=944,R=0.053,Rw=0.072.The compound consists of two [Na(B15C5)]+ complex cations and a [Pd(SCN)4]2- complex anion.Each sodium ion is coordinated by five crown ether oxygen atoms and one N atom from the SCN group of [Pd(SCN)4]2- to form stable neutral complex.  相似文献   

4.
The reaction of Pd(OAc)2 with bis-iminophosphoranes Ph3P=NCH2CH2CH2N=PPh3 (1a), [C6H4(C(O)N=PPh3)2-1,3] (1b) and [C6H4(C(O)N=PPh3)2-1,2] (1c), gives the orthopalladated tetranuclear complexes [{Pd(mu-Cl){C6H4(PPh2=NCH2-kappa-C,N)-2}}2CH2]2 (2a) [{Pd(mu-OAc){C6H4(PPh2=NC(O)-kappa-C,N)-2}}2C6H4-1',3']2 (2b) and [{Pd(mu-OAc){C6H4(PPh2=NC(O)-kappa-C,N)-2}}2C6H4-1',2']2 (2c). The reaction takes place in CH2Cl2 for 1a, but must be performed in glacial acetic acid for 1b and 1c. The process implies in all cases the activation of a C-H bond on a Ph ring of the phosphonium group, with concomitant formation of endo complexes. This is the expected behaviour for 1a, but for 1b and 1c reverses the exo orientation observed in other ketostabilized iminophosphoranes. The influence of the solvent in the orientation of the reaction is discussed. The dinuclear acetylacetonate complexes [{Pd(acac-O,O'){C6H4(PPh2=NCH2-kappa-C,N)-2}}2CH2] (3a), [{Pd(acac-O,O'){C6H4(PPh2=NC(O)-kappa-C,N)-2}}2C6H4-1',3'] (3b) and [{Pd(acac-O,O'){C6H4(PPh2=NC(O)-kappa-C,N)-2}}2C6H4-1',2'] (3c) have been obtained from the halide-bridging tetranuclear derivatives. The X-ray crystal structure of [3c.4CHCl3] is also reported.  相似文献   

5.
<正> [Pd(u-Ph2Ppy)Cl]2.0. 3CH2C12, Mr = 835. 70, monoclinic, space group C2/c with a=30. 405(4), b= 17. 868(2),c=12. 955(2) A,B=98. 40(1) ,V = 6962. 6A3;Z=8,Dx=1. 59 g/cm3,final R=0. 044 and Rw= 0. 058 for 3190 observed independent reflections. The distance between the two palladium atoms is 2. 5885(4) A. Each Pd ( I ) atom has a square-planar stereochemistry . There is a pronounced twist ad-out the Pd-Pd bond with the result that the dihedral angle between the coordination planes of two Pd atoms is 37. 6.  相似文献   

6.
The reaction of Pd(OAc)(2) with polyfunctional iminophosphoranes Ph(3)P=NCH(2)CO(2)Me (1a), Ph(3)P=NCH(2)C(O)NMe(2) (1b), Ph(3)P=NCH(2)CH(2)SMe (1c) and Ph(3)P=NCH(2)-2-NC(5)H(4) (1d), gives the orthopalladated dinuclear complex [Pd(mu-Cl){C(6)H(4)(PPh(2)=NCH(2)CO(2)Me-kappa-C,N)-2}](2) (2a) and the mononuclear derivatives [PdCl{C(6)H(4)(PPh(2)=NCH(2)CONMe(2)-kappa-C,N,O)-2}] (2b), [PdCl{C(6)H(4)(PPh(2)=NCH(2)CH(2)SMe-kappa-C,N,S)-2}] (2c) and [PdCl{C(6)H(4)(PPh(2)=NCH(2)-2-NC(5)H(4)-kappa-C,N,N)-2}] (2d). The reaction implies the activation of a C-H bond in a phenyl ring of the phosphonium group, this fact being worthy of note due to the strongly deactivating nature of the phosphonium unit. The palladacycle containing the metallated carbon atom is remarkably stable toward the coordination of incoming ligands, while that formed by the iminic N atom and another heteroatom (O, 2a and 2b; S, 2c; N, 2d) is less stable and the resulting complexes can be considered as hemilabile. The X-ray crystal structures of the cyclopalladated [Pd(mu-Cl){C(6)H(4)(PPh(2)=NCH(2)CO(2)Me-kappa-C,N)-2}](2) (2a), [PdCl{C(6)H(4)(PPh(2)=NCH(2)-2-NC(5)H(4)-kappa-C,N,N)-2}] (2d), [Pd{C(6)H(4)(PPh(2)=NCH(2)CONMe(2)-kappa-C,N,O)-2}(NCMe)](ClO(4)) (7b) and [Pd{C(6)H(4)(PPh(2)NCH(2)CONMe(2)-kappa-C,N,O)-2}(py)](ClO(4)) (3b), and the coordination compound cis-[Pd(Cl)(2)(Ph(3)P=NCH(2)CH(2)SMe-kappa-N,S)] (8) are also reported.  相似文献   

7.
The title complex Pd(C13H15N2O3)2(C13H15N2O3))- is the anion of isonitrosoethylacetoacetate-N-benzylimine) crystallizes in the monoclinic system, space group P21/c with a= 8. 197(2), b= 14. 524(3), c= 10. 835(2) A , β= 101.77(3)°, V= 1262. 8(5) A3, Dc=1. 580 g/cm3, F(000)=616, Mr= 600. 94, μ(MoKα) =0. 784mm-1, Z=2 and final R=0. 0410 and wR=0. 0962 for 1855 observed reflections [I≥2σ(I)]. The geometry around the palladium atom is a distorted trans PdN4 square plane, the Schiff base ligand C6H5CH2-IEAI- being coordinated through its oximo-nitrogen atom and imino-nitrogen atom.  相似文献   

8.
<正> C_18H_28N_4O_14Sb_2, MT = 767. 94, monoclinic, space group P2_1/c, a = 13. 847(2),b=6.866(2),c=13. 846(2) A,β=116. 46(1)°,V=1180. 3A3,Z=2,Dc = 2. 161g/cm3, F(000) = 756,μ(MoKa) = 23. 83cm-1. R and Rw were 0.054 and 0. 060, respectively, for 1357 observed reflections at room temperature. Each binuclear complexes arranged so that the centre of the carbon-carbon bond in the ethylenediamine group lies on a crystallographic centre of inversion. The ethylenediamine group forms a bridge between the two halves of the title molecule. Each antimony atom is ψ-heptacoordi-nated by a lone electron pair,one O atom from a water molecucle,one O atom from an ac-etato group and two amino N atoms at the equatorial plane as well as two O atoms from the acetato groups at the axial positions forming a pentagonal bipyramid.  相似文献   

9.
The title complex [CoL(H20)3]2·H2O (C26H46N4O21S4CO2), where L = taurine-5- methyl-2-hydroxyisophthalaldehydes, has been synthesized and characterized by IR and X-ray diffraction analysis. The crystal of the complex belongs to the triclinic system, space group P1, with a = 11.197(4), b = 13.309(5), c = 14.486(5) ]A, a = 78.827(13),β = 70.547(11), γ = 81.058(13)°, Mr = 996.77, S = 1.08, V= 1987.2(13) A3, Z = 2, Dc = 1.666 g/cm3, F(000) = 1032,μ = 1.131 mm^-1, R = 0.0633 and wR = 0.1293. According to the structural analysis, the Co( Ⅱ ) ion adopts a slightly distorted six-coordinated octahedral geometry. One N atom of the Schiff base of each molecule was hydrogenated to form hydrogen bond with O atom. Two coterminous molecules packed in one crystal water molecule are linked by intermolecular hydrogen bonds, thus generating an infinite chain constructed by hydrogen bonds.  相似文献   

10.
<正> C35.5H31FePdCl2O0.5P2 ({dichloro-[1,1' -bis (diphenyl) phosphino]-fer-rocene}palladium (Ⅱ) hemi acetone solvate) ,Mr = 760. 74,monoclinic,space group C2/ c,a=33. 993(4),b=10. 424(3),c=18. 364(4) A ,β=104. 52(1)°,V = 6299A3,Z= 8,DC=1.67 g/cm3,μ= 13. 3cm-1,F(000) = 3200,final R= 0.075 for 2058 observed reflections. The environment of the Pd atom is described as a square plane with two cis-chlorine atoms and two phosphorus atoms. The [1, 1'-bisdiphenylphospino] ferrocene (dppf) group is connected to the Pd atom as a bidentate ligand. The Pd-P distances are 2. 278(5) and 2. 278(6) A ;the Pd-Cl distances 2. 323(6) and 2. 345(6) A.  相似文献   

11.
吴琼洁  刘世雄 《结构化学》2004,23(10):1177-1182
本文合成了含水杨醛缩对硝基苯甲酰腙(简写为H2L)的钒酰配合物VOL(CH3OH)(CH3O)(1,C16H16N3O7V,Mr=413.26)和钴配合物[CoL(C5H5N)3]NO3C5H5N(2,C34H29N8O7Co,Mr=720.58)。配合物1属单斜晶系,空间群为P21/c,a=7.3253(3),b=18.8237(9),c=12.9014(5)?b=91.672(1),V=1778.2(1)3,Z=4,F(000)=848,m(MoKa)=0.603mm1,R=0.0470,wR=0.1312。配合物2属单斜晶系,空间群为P21/c,a=11.4196(8),b=17.157(1),c=17.081(1)?b=96.8233(9),V=3323.0(4)3,Z=4,F(000)=1488,m(MoKa)=0.578mm1,R=0.0455,wR=0.1311。在配合物1中,钒(V)原子由周围的酰氧基原子、配体L2的3个配位原子,去质子化甲醇的甲氧基原子和配位甲醇的氧原子配位,形成畸变的VO(ONO)(O)(O)八面体配位构型。晶体内每2个分子间通过氢键作用缔合成中心对称的分子对,OH…N氢键键长为2.861(4)?键角163.20。晶体中存在着弱p-p共轭作用。在配合物2中,钴(Ⅲ)原子由1个L2的3个配位原子和3个配位吡啶分子的3个氮原子配位,呈N4O2八面体配位构型。  相似文献   

12.
<正> N-(para-chloro)-phenyl iminodiacetic acid hydrate ethanol solvate ClC6H4N(CH2COOH)2· H2O·C2H5OH, Mr = 307.73, monoclinic, P21/n, Cu-Ka (λ=1. 5410(?)), a = 16. 732(1), b = 5. 337(1), c=16. 300(1)(?) ,β=108. 52(1)°, V = 1380. 1(?)3, Z = 4, Dc=1.481g.cm-3, * = 27. 172cm-1, F(000) = 648, final R = 0. 072 for 1610 observed reflections. The crystal structure consists of discrete molecule of N-(para-chloro)-phenyl iminodiacetic acid, hydrate as well as ethanol solvate. A big ring consisting of atoms O(3), C(3), C(4), N(1), C(2), C(1), O(2) and H(2) is nearly planar with the maximum deviation of the atom N(1) of 0. 54 (?). Owing to the intramolecular hydrogen bond O(2)-H(2)…O(3) , the bond C(3) -O(3) in the COOH group is longer than the bond C(3)-O(4).  相似文献   

13.
A palladium(Ⅱ) complex, [PdLCl]2· [PdCl4], [L=4-bromo-2,6-bis(N,N-diethylaminomethylene)pyridine], was synthesized and its crystal structure was determined by X-ray analysis. The complex crystallizes in monoclinic system with space group Cc, a=0.845 1(17) nm, b=1.836 5(4) nm, c=2.715 8(5) nm,β=93.99(3)°, V=4.204 8(15) nm^3, Z=4, R,=0.037 7 and wR2=0.076 9. The coordination geometry of the Pd atom in the cation is a slightly distorted square planar, with one pyridyl N and two N atoms of the diethylamine ligand, together with one Cl atom. The dihedral angle between the square planar (N3PdCl) and the pyridyl ring is 10.3(4)°. CCDC: 623421.  相似文献   

14.
Yih KH  Lee GH  Wang Y 《Inorganic chemistry》2000,39(12):2445-2451
Treatment of the complex [W(CO)5[PPh2(CS2Me)]] (2) with [Pd(PPh3)4] (1) affords binuclear complexes such as anti-[(Ph3P)2Pd[mu-eta 1,eta 2-(CS2Me)PPh2]W(CO)5] (3), syn-[(Ph3P)2Pd[mu-eta 1,eta 2-(CS2Me)PPh2]W(CO)5] (4), and trans-[W(CO)4(PPh3)2] (5). In 3 and 4, respectively, the W and Pd atoms are in anti and syn configurations with respect to the P-CS2 bond of the diphenyl(dithiomethoxycarbonyl)phosphine ligand, PPh2(CS2Me). Complex 3 undergoes extensive rearrangement in CHCl3 at room temperature by transfer of a PPh3 ligand from Pd to W, eliminating [W(CO)5(PPh3)] (7), while the PPh2CS2Me ligand transfers from W to Pd to give [[(Ph3P)Pd[mu-eta 1,eta 2-(CS2Me)PPh2]]2] (6). In complex 6, the [Pd(PPh3)] fragments are held together by two bridging PPh2(CS2Me) ligands. Each PPh2(CS2Me) ligand is pi-bonded to one Pd atom through the C=S linkage and sigma-bonded to the other Pd through the phosphorus atom, resulting in a six-membered ring. Treatment of Pd(PPh3)4 with [W(CO)5[PPh2[CS2(CH2)nCN]]] (n = 1, 8a; n = 2, 8b) in CH2Cl2 affords syn-[(Ph3P)2Pd[mu-eta 1,eta 2-[CS2(CH2)nCN]PPh2]W(CO)5] (n = 1, 9a; n = 2, 9b). Similar configurational products syn-[(Ph3P)2Pd[mu-eta 1,eta 2-(CS2R)PPh2]W(CO)5] (R = C2H5, C3H5, C2H4OH, C3H6CN, 11a-d) are synthesized by the reaction of Pd(PPh3)4 with [W(CO)5[PPh2(CS2R)]] (R = C2H5, C3H5, C2H4OH, C3H6CN, 10a-d). Although complexes 11a-d have the same configuration as 9a,b, the SR group is oriented away from Pd in the former and near Pd in the latter. In these complexes, the diphenyl(dithioalkoxycarbonyl)phosphine ligand is bound to the two metals through the C=S pi-bonding and to phosphorus through the sigma-bonding. All of the complexes are identified by spectroscopic methods, and the structures of complexes 3, 6, 9a, and 11d are determined by single-crystal X-ray diffraction. Complexes 3, 9, and 11d crystallize in the triclinic space group P1 with Z = 2, whereas 6 belongs to the monoclinic space group P2/c with Z = 4. The cell dimensions are as follows: for 3, a = 10.920(3) A, b = 14.707(5) A, c = 16.654(5) A, alpha = 99.98(3) degrees, beta = 93.75(3) degrees, gamma = 99.44(3) degrees; for 6, a = 15.106(3) A, b = 9.848(3) A, c = 20.528(4) A, beta = 104.85(2) degrees; for 9a, a = 11.125(3) A, b = 14.089(4) A, c = 17.947(7) A, alpha = 80.13(3) degrees, beta = 80.39(3) degrees, gamma = 89.76(2) degrees; for 11d, a = 11.692(3) A, b = 13.602(9) A, c = 18.471(10) A, alpha = 81.29(5) degrees, beta = 80.88(3) degrees, gamma = 88.82(1) degrees.  相似文献   

15.
<正> Crystal and molecular structure of [(C4H9)4N][O2MoS2Cutu] (tu-thiourea) has been determined by X-ray diffraction technique. The crystal is monoclinic, space group P21/n, with a = 11.871(4), b=13.920(2), c= 15.814(11)A;β= 90.22(4)°,V=2613.2A3,Z = 4, DC= 1.459, Do = 1.46g/cm3. The final R and Rw are 0.049 and 0.056, respectively. The title complex has a rhombic planar MoCu(μ-S)2 core with Mo-Cu distance of 2.647A.The Ho atom is tetrahedrally coordinated by two 0 atoms and two u-S atoms. The Cu-S(tu) bond length of 2.191 A is significantly shorter than the Cu-S(bridge) in analogues.  相似文献   

16.
黄君珉  陈茹玉 《结构化学》2001,20(5):354-357
1 INTRODUCTIONOrganophosphorus compounds are ubiquitous in nature and they have broad applications in the fields of agriculture and medicine. During the past two decades, (-ketophosphonates and their derivatives containing sulfur have attracted considerable attention because these compounds are endowed with special physical, chemical and pharmacological properties due to the proximity of the carbonyl and the phosphoryl groups[1~8]. In the study on new pharmacenticals and agrochemicals, th…  相似文献   

17.
The imidazolium salts [3-R1-1-{2-Ar-imino)-2-R2-ethyl}imidazolium] chloride (C-N; Ar = 2,6-iPr2C6H3; R1/R2 = Me/Me (a), Me/Ph (b), Ph/Me (c), 2,4,6-Me3C6H2 (d), 2,6-iPr2C6H3 (e)) react with Ag(2)O to give Ag(I) iminocarbene complexes (C-N)AgCl (4a-e) in which the iminocarbene ligand is bonded to Ag via the imidazoline-2-ylidene carbon atom. The solid-state structures of 4b and 4d were determined by X-ray crystallography and revealed the presence of monomeric (carbene)AgCl units with Z and E configurations at the imine C=N bonds, respectively. Carbene transfer to Pd occurs when compounds 4b-e are treated with (COD)PdCl2 to yield bis(carbene) complexes (C-N)2PdCl2 (6b-e) containing two kappa1-C bonded iminocarbene moieties. NMR spectroscopic data indicated a trans coordination geometry at Pd. This conclusion was supported by an X-ray structure determination of 6b which clearly demonstrated the non-chelating nature of the iminocarbene ligand system. EXSY 1H NMR spectroscopy suggests that the non-chelating structures undergo E/Z isomerization at the imine C[double bond, length as m-dash]N double bonds in solution. The preparative results contrast our earlier report that the reaction between 4a and (COD)PdCl2 results in a chelating kappa2-C,N bonded iminocarbene complex (C-N)PdCl2. The coordination mode and dynamic behavior of the iminocarbene ligand systems have been found to be dramatically affected by changes in the substitution pattern of the ligand system. Sterically unencumbered systems (a) favor the formation of kappa2-C,N chelate structures containing one iminocarbene moiety per metal upon coordination at Pd(II); these complexes were demonstrated to engage in reversible, solvent-mediated chelate ring-opening reactions. Sterically encumbered systems (b-e) form non-chelating kappa1-C iminocarbene Pd(II) complexes containing two iminocarbene ligands per metal. Transannular repulsions across the chelate ring are believed to be the origin of these structural differences.  相似文献   

18.
The mechanism for the activation of the sigma bonds, the O-H of H2O, C-H of CH4, and the H-H of H2, and the pi bonds, the C[triple bond]C of C2H2, C=C of C2H4, and the C=O of HCHO, at the Pd=X (X = Sn, Si, C) bonds of the model complexes (H2PC2H4PH2)Pd=XH2 5 has been theoretically investigated using a density functional method (B3LYP). The reaction is significantly affected by the electronic nature of the Pd=X bond, and the mechanism is changed depending on the atom X. The activation of the O-H bond with the lone pair electron is heterolytic at the Pd=X (X = Sn, Si) bonds, while it is homolytic at the Pd=C bond. The C-H and H-H bonds without the lone pair electron are also heterolytically activated at the Pd=X bonds independent of the atom X, where the hydrogen is extracted as a proton by the Pd atom in the case of X = Sn, Si and by the C atom in the case of X=C because the nucleophile is switched between the Pd and X atoms depending on the atom X. In contrast, the pi bond activation of C[triple bond]C and C=C at the Pd=Sn bond proceeds homolytically, and is accompanied by the rotation of the (H2PC2H4PH2)Pd group around the Pd-Sn axis to successfully complete the reaction by both the electron donation from the pi orbital to Sn p orbital and the back-donation from the Pd dpi orbital to the pi orbital. On the other hand, the activation of the C=O pi bond with the lone pair electron at the Pd=Sn bond has two reaction pathways: one is homolytic with the rotation of the (H2PC2H4PH2)Pd group and the other is heterolytic without the rotation. The role of the ligands controlling the activation mechanism, which is heterolytic or homolytic, is discussed.  相似文献   

19.
The title compound bis(1-(4-(dimethylamino)benzylidene)-4-phenylthiosemicar-bazato)-palladium(Ⅱ)(PdL2) was obtained by reacting 1-(4-(dimethylamino)benzylidene)-4-phenyl-thiosemicarbazide with dichlorobis(benzonitrile)palladium(Ⅱ) in methanol,and its structure was characterized by single-crystal X-ray diffraction.The crystal of PdL2 was obtained in dimethyl-formamide(DMF) solvent with solvent molecules involved in the cell and crystallizes in the monoclinic system,space group C2 with a = 18.485(15),b = 7.090(5),c = 17.595(11) ,β = 121.21(3)o,V = 1972(2) 3,Z = 2,Mr = 847.40,Dc = 1.427 g/cm3,μ = 0.624 mm-1,F(000) = 880,R = 0.0607 and wR = 0.1358.The Pd atom adopts a distorted square planar coordination geometry with two Pd-N and two Pd-S bonds.The ligand loses a proton from its tautomeric thiol form and coordinates to the Pd atom via mercapto sulfur and the imine nitrogen atom,which binds to palladium as bidentate N,S-donors forming five-membered chelate rings.The complex formed hydrogen bonding interaction with solvent DMF molecules from the hydrogen of phenylamine to the oxygen of DMF and several intramolecular hydrogen bonds.Pd(Ⅱ) perturbed ligand π-π* transition and metal-to-ligand charge transfer(MLCT) transition are observed in its electronic absorption spectra.The complex exhibits intraligand 1π-π*(IL) state and MLCT state dual fluorescent emissions in organic solvent at room temperature.  相似文献   

20.
王博义  刘之俊 《结构化学》1989,8(4):283-288
本文报导了咪唑桥异双核配合物[(Ida)CuImCo(NH_3)_5](ClO_)4)_2·4H_2O(Ida为亚氨基二乙酸,Im=咪唑)的晶体结构。晶体属单斜晶系,空间群为P2_1/c,M_r=676.5,Z=4,D_c=1.911g/cm~3,晶胞参数为a=13.024(2),b=15.400(2),c=13.198(4)A,β=111.28(2)°。结构用直接法解出,经全矩阵最小二乘法修正,最后R因子为0.062。在分子中Cu(Ⅱ)处于Ida的两个0和一个N,咪唑的一个N及稍远处一个H_2O的O组成的变形四方锥配位环境中;Co(Ⅱ)则与5个NH_3及咪唑的另一个N配位,形成略有变形的八面体构型。对配位阳离子的CNDO/2计算表明,该配合物具有一定的催化O_(2-)歧化活性。  相似文献   

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