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1.
Reaction of the ligands 3-phenyl-5-(2-pyridyl)pyrazole (HL1), 3,5-bis(2-pyridyl)pyrazole (HL2), 3-methyl-5-(2-pyridyl)pyrazole (HL3) and 3-methyl-5-phenylpyrazole (HL4) with [MCl2(CH3CN)2] (M = Pd(II), Pt(II)) or [PdCl2(cod)] gives complexes with stoichiometry [PdCl2(HL)2] (HL = HL1, HL2, HL3), [Pt(L)2] (L = L1, L2, L3) and [MCl2(HL4)2] (M = Pd(II), Pt(II)). The new complexes were characterised by elemental analyses, conductivity measurements, infrared and 1H NMR spectroscopies. The crystal and molecular structure of [PdCl2(HL1)] was resolved by X-ray diffraction, and consists of monomeric cis-[PdCl2(HL1)] molecules. The palladium centre has a typical square planar geometry, with a slight tetrahedral distortion. The tetra-coordinated metal atom is bonded to one pyridine nitrogen, one pyrazolic nitrogen and two chloro ligands in a cis disposition. The ligand HL1 is not completely planar.  相似文献   

2.
Two new pyrazole-derived ligands, 1-ethyl-3,5-bis(2-pyridyl)pyrazole (L1) and 1-octyl-3,5-bis(2-pyridyl)pyrazole (L2), both containing alkyl groups at position 1 were prepared by reaction between 3,5-bis(2-pyridyl) pyrazole and the appropriate bromoalkane in toluene using sodium ethoxide as base.The reaction between L1, L2 and [MCl2(CH3CN)2] (M = Pd(II), Pt(II)) resulted in the formation complexes of formula [MCl2(L)] (M = Pd(II), L = L1 (1); M = Pd(II), L = L2 (2); M = Pt(II), L = L1 (3); M = Pt(II), L = L2 (4)). These complexes were characterised by elemental analyses, conductivity measurements, infrared, 1H, 13C{1H} NMR and HMQC spectroscopies. The X-ray structure of the complex [PtCl2(L2)] (4) was determined. In this complex, Npyridine and Npyrazole donor atoms coordinate the ligand to the metal, which complete its coordination with two chloro ligands in a cis disposition.  相似文献   

3.
Cytidine (cyt) and adenosine (ado) react with cis-[L2Pt(μ-OH)]2(NO3)2 (L = PMe3, PPh3) in various solvents to give the nucleoside complexes cis-[L2Pt{cyt(− H),N3N4}]3(NO3)3 (L = PMe3, 1),cis-[L2Pt{cyt(− H),N4}(cyt,N3)]NO3 (L = PPh3, 2), cis-[L2Pt{ado(− H),N1N6}]2(NO3)2 (L = PMe3, 3) and cis-[L2Pt{ado(− H),N6N7}]NO3 (L = PPh3, 4). When the condensation reaction is carried out in solution of nitriles (RCN, R = Me, Ph) the amidine derivatives cis-[(PPh3)2PtNH=C(R){cyt(− 2H)}]NO3 (R = Me, 5a; R = Ph, 5b) and cis-[(PPh3)2PtNH=C(R){ado(− 2H)}]NO3 (R = Me, 6a: R = Ph, 6b) are quantitatively formed. The coordination mode of these nucleosides, characterized in solution by multinuclear NMR spectroscopy and mass spectrometry, is similar to that previously observed for the nucleobases 1-methylcytosine (1-MeCy) and 9-methyladenine (9-MeAd). The cytotoxic properties of the new complexes, and those of the nucleobase analogs, cis-[(PPh3)2PtNH=C(R){1-MeCy(− 2H)}]NO3 (R = Me, 7a: R = Ph, 7b), cis-[(PPh3)2PtNH=C(R){9-MeAd(− 2H)}]NO3 (R = Me, 8a: R = Ph, 8b) have been investigated in a wide panel of human cancer cells. Interestingly, whereas the Pt(II) nucleoside complexes (1-4) did not show appreciable cytotoxicity, the corresponding amidine derivatives (7a, 7b, 8a, 8b, 5b, and 6b) exhibited a significant in vitro antitumor activity.  相似文献   

4.
The “amidate-hanging” Pt mononuclear complexes, which can easily bind a second metal ion with the non-coordinated oxygen atoms in the amidate moieties, have been synthesized and characterized by 1H NMR, MS, IR spectroscopy, and single crystal X-ray analysis. Five new complexes with various amidate ligands and co-ligands, cis-[Pt(PVM)2(en)] · 4H2O (1, PVM = pivaloamidate, en = ethylenediamine), cis-[Pt(PVM)2(NH2CH3)2] · H2O (2), cis-[Pt(PVM)2(NH2tBu)2] (3), cis-[Pt(TCM)2(NH3)2] (4, TCM = trichloroacetamidate), and cis-[Pt(BZM)2(NH3)2] (5, BZM = benzamidate), were successfully synthesized by direct base hydrolysis of the corresponding Pt nitrile complexes, cis-[Pt(NCR)2(Am)2]2+ (P1, P2, P3, and P5) (NCR = nitrile, Am = amine). These nitrile complexes were obtained by introducing nitriles into the Pt aqua complexes, cis-[Pt(OH2)2(Am)2](ClO4)2, whereas introduction of trichloronitrile into [Pt(OH2)2(NH3)2](ClO4)2 induced more facilitated water nucleophilic attack to afford [Pt(TCM)(NH(COH)CCl3)(NH3)2](ClO4) (P4). The base treatments of the precursor complexes (P1-5) lead to produce “amidate-hanging” Pt mononuclear complexes (1-5) without geometry isomerization. The 195Pt chemical shifts for 1-5 exhibit subtle differences of the Pt electron densities among them.  相似文献   

5.
The interaction of an excess of the title ligands L with the cis-Pt(phos)2 moieties gives compounds a-bcis-[Pt(L-O)2(phos)2] (a, phos = P(Ph)3; b, phos = 1/2 dppe), in which O- is preferred to S-coordination. Such preference is confirmed by the fact that the same products are obtained by reaction of excess of L with the previously reported a-d complexes [Pt(L-O,S)(phos)2]+, (c, phos = PPh3, d, phos = 1/2 dppe), for which chelate ring opening occurs with rupture of Pt-S rather than Pt-O bonds. Compound a can be obtained also by oxidative addition of HL to [Pt(PPh3)3]. The Pt-O bonds in compounds a-d are stable towards substitution by Me2SO, pyridine and tetramethylthiourea. Substitution of L’s occurs with N,N′-diethyldithiocarbamate, which forms a very stable chelate with Pt(II). Thiourea and N,N′-dimethylthiourea also react, because they give rise to cyclometallated products [Pt(phos)2(NRC(S)NHR)]+ (R = H, CH3), with one ionised thioamido group, as revealed by an X-ray investigation of [Pt(PPh3)2(NHC(S)NH2)]+. The preference of O versus S coordination, as well as the stability of the Pt-O bonds, are discussed in terms of antisymbiosis.  相似文献   

6.
The synthesis and characterization of several complexes of the composition [{M(terpy)}n(L)](ClO4)m (M = Pt, Pd; L = 1-methylimidazole, 1-methyltetrazole, 1-methyltetrazolate; terpy = 2,2′:6′,2″-terpyridine; n = 1, 2; m = 1, 2, 3) is reported and their applicability in terms of a metal-mediated base pair investigated. Reaction of [M(terpy)(H2O)]2+ with 1-methylimidazole leads to [M(terpy)(1-methylimidazole)](ClO4)2 (1: M = Pt; 2: M = Pd). The analogous reaction of [Pt(terpy)(H2O)]2+ with 1-methyltetrazole leads to the organometallic compound [Pt(terpy)(1-methyltetrazolate)]ClO4 (3) in which the aromatic tetrazole proton has been substituted by the platinum moiety. For both platinum(II) and palladium(II), doubly metalated complexes [{M(terpy)}2(1-methyltetrazolate)](ClO4)3 (4: M = Pt; 5: M = Pd) can also be obtained depending on the reaction conditions. In the latter two compounds, the [M(terpy)]2+ moieties are coordinated via C5 and N4. X-ray crystal structures of 1, 2, and 3 are reported. In addition, DFT calculations have been carried out to determine the energy difference between fully planar [Pd(mterpy)(L)]2+ complexes Ip-IVp (mterpy = 4′-methyl-2,2′:6′,2″-terpyridine; L = 1-methylimidazole-N3 (I), 1-methyl-1,2,4-triazole-N4 (II), 1-methyltetrazole-N3 (III), or 3-methylpyridine-N1 (IV)) and the respective geometry-optimized structures Io-IVo. Whereas this energy difference is larger than 70 kJ mol−1 for compounds I, II, and IV, it amounts to only 0.8 kJ mol−1 for the tetrazole-containing complex III, which is stabilized by two intramolecular C-H?N hydrogen bonds. Of all complexes under investigation, only the terpyridine-metal ion-tetrazole system with N3-coordinated tetrazole appears to be suited for an application in terms of a metal-mediated base pair in a metal-modified oligonucleotide.  相似文献   

7.
The reaction of trans(N)-[Co(d-pen)2] (pen = penicillaminate) with HgCl2 or HgBr2 in the molar ratios of 1:1 gave the sulfur-bridged heterodinuclear complex, [HgX(OH2){Co(d-pen)2}] (X = Cl (1a) or Br (1b)). A similar reaction in the ratio of 2:1 produced the trinuclear complex, [Hg{Co(d-pen)2}2] (1c). The enantiomers of 1a and 1c, [HgCl(OH2){Co(l-pen)2}] (1a′) and [Hg{Co(l-pen)2}2] (1c′), were also obtained by using trans(N)-[Co(l-pen)2] instead of trans(N)-[Co(d-pen)2]. Further, the reaction of cis · cis · cis-[Co(d-pen)(l-pen)] with HgCl2 in the molar ratio of 1:1 resulted in the formation of [HgCl(OH2){Co(d-pen)(l-pen)}] (2a). During the formations of the above six complexes, 1a, 1b, 1c, 1a′, 1c′, and 2a, the octahedral Co(III) units retain their configurations. On the other hand, the reaction of cis · cis · cis-[Co(d-pen)(l-pen)] with HgCl2 in the molar ratio of 2:1 gave not [Hg{Co(d-pen)(l-pen}2] but [Hg{Co(d-pen)2}{Co(l-pen)2}] (2c), accompanied by the ligand-exchange on the terminal Co(III) units. The X-ray crystal structural analyses show that the central Hg(II) atom in 1c takes a considerably distorted tetrahedral geometry, whereas that in 2c is of an ideal tetrahedron. The interconversion between the complexes is also examined. The electronic absorption, CD, and NMR spectral behavior of the complexes is discussed in relation to the crystal structures of 1c and 2c.  相似文献   

8.
The distorted square-planar complexes [Pd(PNHP)Cl]Cl (1) (PNHP = bis[2-(diphenylphosphino)ethyl]amine), [M(P3)Cl]Cl [P3 = bis[2-(diphenylphosphino)ethyl]phenylphosphine; M = Pd (2), Pt (3)] and [Pt(NP3)Cl]Cl (5) (NP3 = tris[2-(diphenylphosphino)ethyl]amine), coexisting in the later case with a square-pyramidal arrangement, react with one equivalent of CuCl to give the mononuclear heteroionic systems [M(L)Cl](CuCl2) [L = PNHP, M = Pd (1a); L = P3, M = Pd (2a), Pt (3a); L = NP3, M = Pt (5a)]. The crystal structure of 3a confirms that Pt(II) retains the distorted square-planar geometry of 3 in the cation with P3 acting as tridentate chelating ligand, the central P atom being trans to one chloride. The counter anion is a nearly linear dichlorocuprate(I) ion. However, the five-coordinate complexes [Pd(NP3)Cl]Cl (4), [M(PP3)Cl]Cl (M = Pd (6), Pt (7); PP3 = tris[2-(diphenylphosphino)ethyl] phosphine) containing three fused five-membered chelate rings undergo a ring-opening by interaction with one (4, 6, 7) and two (6, 7) equivalents of CuCl with formation of neutral MCu(L)Cl3 [L = NP3, M = Pd (4a); L = PP3, M = Pd (6a), Pt (7a)] and ionic [MCu(PP3)Cl2](CuCl2) [M = Pd (6b), Pt (7b)] compounds, respectively. The heteronuclear systems were shown by 31P NMR to have structures where the phosphines are acting as tridentate chelating ligands to M(II) and monodentate bridging to Cu(I). Further additions of CuCl to the neutral species 6a and 7a in a 1:1 ratio resulted in the achievement of the ionic complexes 6b and 7b with ions as counter anions. It was demonstrated that the formation of heterobimetallic or just mononuclear mixed salt complexes was clearly influenced by the polyphosphine arrangement with the tripodal ligands giving the former compounds. However, complexes [M(NP3)Cl]Cl constitute one exception and the type of reaction undergone versus CuCl is a function of the d8 metal centre.  相似文献   

9.
The preparation of a series of 1,2-phenylenedioxoborylcyclopentadienyl-metal complexes is described. These are of formula [M{η5-C5H4(BX)}Cl3] [M = Ti and X = CAT (2a), CATt (2b) or CATtt (2c); X = CATtt and M = Zr (4a) or Hf (4b)], [M{η5-C5H4(BX)}2Cl2] [M = Zr, X = CAT (3a) or CATt (3c); or M = Hf, X = CAT (3b) or CATt (3d)], [M{(μ-η5-C5H3BCAT)2 SiMe2}Cl2] [M = Zr (5a) or Hf (5b)], [M{η5-C5H3(BCAT)2}Cl3] [M = Zr (6a) or Hf (6b)], [M{η5-C5H4BCAT}3(THF)] [M = La (7a), Ce (7b) or Yb (7c)], [Sn{η5-C5 H4(BCATt)}Cl](8) and [Fe{η5-C5H4(BCATt)}2] (9). The abbreviations refer to BO2C6H4-1,2 (BCAT) and the 4-But (BCATt) and the (BCATtt) analogues. The compounds 2a-9 have been characterised by microanalysis, multinuclear NMR and mass spectra. The single crystal X-ray structure of the lanthanum compound 7a is presented.  相似文献   

10.
Complexes [Cu(HSas)(H2O)] · 2H2O (H3Sas = N-(2-hydroxybenzyl)-l-aspartic acid) (1), [Cu(HMeSglu)(H2O)] · 2H2O (H3MeSglu = (N-(2-hydroxy-5-methylbenzyl)-l-glutamic acid) (2), [Cu2(Smet)2] (H2Smet = (N-(2-hydroxybenzyl)-l-methionine) (3), [Ni(HSas)(H2O)] (4), [Ni2(Smet)2(H2O)2] (5), and [Ni(HSapg)2] (H2Sapg = (N-(2-hydroxybenzyl)-l-aspargine) (6) have been synthesized and characterized by chemical and spectroscopic methods. Structural determination by single crystal X-ray diffraction studies revealed 1D coordination polymeric structures in 2 and 4, and hydrogen-bonded network structure in 5 and 6. In contrast to previously reported coordination compounds with similar ligands, the phenol remains protonated and bonded to the metal ions in 2 and 4, and also probably in 1. However, the phenolic group is non-bonded in 6.  相似文献   

11.
Schiff bases of 2-hydroxybenzophenone (HBP) (C6H5)(2-HOC6H4)CN(CH2)nEAr (L1/L2: E = S, Ar = Ph, n = 2/3; L3/L4: E = Se, Ar = Ph, n = 2/3; L5/L6: E = Te, Ar = 4-MeOC6H4, n = 2/3) and their complexes [PdCl(L-H)] (L = L1L6; 1, 2, 3, 5, 7, 11), [PtCl(L3-H/L5-H)] (4/8), [PtCl2(L4/L6)2] (6/12), [(p-cymene)RuCl(L5/L6)]Cl (9/13) and [HgBr2(L5/L6)2] (10/14) have been synthesized and characterized by proton, carbon-13, selenium-77 and tellurium-125 NMR, IR and mass spectra. Single crystal structures of L1, 1, 3, 4, 5 and 7 were solved. The Pd-E bond distances (Å): 2.2563(6) (E = S), 2.3575(6)−2.392(2) (E = Se); 2.5117(5)−2.5198(5) (E = Te) are near the lower end of the bond length range known for them. The Pt-Se bond length, 2.3470(8) Å, is also closer to the short values reported so far. The Heck and Suzuki reaction were carried out using complexes 1, 3, 5 and 7 as catalysts under aerobic condition. The percentage yields for trans product in Heck reaction were found upto 85%.  相似文献   

12.
The electrochemical behavior of the Pt(II)-based Baeyer-Villiger catalysts of the general formulae [Pt(μ-OH)(PP)]2(BF4)2 (PP = dppe (1a), 2Fdppe (1 b), 4Fdppe (1c), dfppe (1d), dmpe (1e), depe (1f), dippe (1g), dtbpe (1h)) and [Pt(OH2)2(PP)](OTf)2 (PP = dppe (2a), 2Fdppe (2b), 4Fdppe (2c), dfppe (2d)) is reported. They exhibit irreversible reduction processes whose potentials reflect the Lewis acidity of the metal centres, showing (for the aromatic diphosphine complexes) overall relations with the number of fluorine atoms, with JPt-P, with the ν(CN) coordination shift of a ligand isocyanide probe and with the catalytic activity. Single-crystal X-ray diffraction analyses were carried out for [Pt(μ-OH)(4Fdppe)]2(BF4)2 (1c) and [Pt(μ-OH) (dippe)]2(BF4)2 (1g).  相似文献   

13.
The aqueous solution behaviour of the equilibrium related cis-[PdCl2(PTA)2] and [PdCl(PTA)3]Cl complexes has been investigated in the presence of acid and iodide ions. Several of the resulting species were identified and a reaction scheme accounting for identified complexes is proposed. The crystal structures of trans-[PdI2(PTA-H)2][PdI3(PTA)]2 · 2H2O (1) (PTA-H+ = protonated form of PTA) and trans-[PdI2(PTA)2] (2) are reported. The geometry around the Pd(II) metal centre in 1 (for both the cation and anion) and 2 is distorted square planar. The PTA ligands occupy a trans orientation in the cation of 1 and in complex 2. Compound 1 represents a rare example of a Pd(II) system wherein the cation:anion pair, in a 1:2 ratio, are both coordination complexes. It is the first d8 Ni-triad square planar complex containing only one PTA ligand and only the second platinum group metal complex. For the cation in 1, the bond distances and angles are Pd(1)-P(1) = 2.2864(16) Å, Pd(1)-I(1) = 2.6216(7) Å, P(1)-Pd(1)-P(1)′ = 180.00(7)° and P(1)-Pd(1)-I(1) = 87.62(4)°, while in the anion the bond distances are Pd(2)-P(2) = 2.2377(15) Å, Pd(2)-I(4) = 2.5961(13) Å, Pd(2)-I(2) = 2.6328(13) Å, Pd(2)-I(3) = 2.6513(8) Å, while the angles are P(2)-Pd(2)-I(4) = 90.00(5)°, P(2)-Pd(2)-I(2) = 89.69(5)°, I(4)-Pd(2)-I(2) = 179.57(2)°, P(2)-Pd(2)-I(3) = 175.19(4)°, I(4)-Pd(2)-I(3) = 90.29(4)° and I(2)-Pd(2)-I(3) = 90.05(4)°. Bond distances and angles of the coordination polyhedron in 2 are Pd-P = 2.327(3) Å, Pd-I = 2.5916(10) Å, P-Pd-I = 89.13(7)° and P-Pd-P = 180.00(13)°. The average effective- and Tolman cone angles for the two ligands, calculated from the crystallographic data, are 115° and 117° for PTA and PTA-H, respectively.  相似文献   

14.
Two unique bimetalic Pt(II) coordination polymers of composition [Ni(hydeten)2Pt(CN)4] (Ni-Pt) and [Cu(hydeten)2Pt(CN)4] (Cu-Pt) [hydeten = N-(2-hydroxyethyl-ethylenediamine) or 2-(2-aminoethylamino)ethanol] have been synthesized and structurally characterized by various methods in this study. The crystal structure of Cu-Pt was determined by single-crystal X-ray diffraction analysis. The structure of Cu-Pt forms of infinite 2,2-TT type [-Cu(hydeten)2-NC-Pt(CN)2-CN-] chains containing paramagnetic copper atoms bridged by tetracyanoplatinate species. In this complex, Cu(II) centers display an axially elongated octahedron with two chelating hydeten molecules in the equatorial positions and N-bonded bridging cyano groups in the axial positions, whereas Pt(II) centers are four coordinate with four cyanide-carbon atoms in a square-planar arrangement. The decrease of the moments of these complexes in temperature range of 50 305 K can assigned to the antiferromagnetic interactions in the structures. The thermal decomposition of Cu-Pt comprise of five distinguished stages, while the thermal decomposition of Ni-Pt take place four different stages.  相似文献   

15.
Reaction of cis-[Ru(acac)22-C8H14)2] (1) (acac = acetylacetonato) with two equivalents of PiPr3 in THF at −25 °C gives trans-[Ru(acac)2(PiPr3)2], trans-3, which rapidly isomerizes to cis-3 at room temperature. The poorly soluble complex [Ru(acac)2(PCy3)2] (4), which is isolated similarly from cis-[Ru(acac)22-C2H4)2] (2) and PCy3, appears to exist in the cis-configuration in solution according to NMR data, although an X-ray diffraction study of a single crystal shows the presence of trans-4. In benzene or toluene 2 reacts with PiPr3 or PCy3 to give exclusively cis-[Ru(acac)22-C2H4)(L)] [L = PiPr3 (5), PCy3 (6)], whereas in THF species believed to be either square pyramidal [Ru(acac)2L], with apical L, or the corresponding THF adducts, can be detected by 31P NMR spectroscopy. Complexes 3-6 react with CO (1 bar) giving trans-[Ru(acac)2(CO)(L)] [L = PiPr3 (trans-8), PCy3 (trans-9)], which are converted irreversibly into the cis-isomers in refluxing benzene. Complex 5 scavenges traces of dinitrogen from industrial grade dihydrogen giving a bridging dinitrogen complex, cis-[{Ru(acac)2(PiPr3)} 2(μ-N2)] (10). The structures of cis-3, trans-4, 5, 6 and 10 · C6H14 have been determined by single-crystal X-ray diffraction. Complexes trans- and cis-3, 5, 6, cis-8, and trans- and cis-9 each show fully reversible one-electron oxidation by cyclic voltammetry in CH2Cl2 at −50 °C with E1/2(Ru3+/2+) values spanning −0.14 to +0.92 V (versus Ag/AgCl), whereas for the vinylidene complexes [Ru(acac)2 (CCHR)(PiPr3)] [R = SiMe3 (11), Ph (12)] the process is irreversible at potentials of +0.75 and +0.62 V, respectively. The trend in potentials reflects the order of expected π-acceptor ability of the ligands: PiPr3, PCy3 <C 2H4 < CCHR < CO. The UV-Vis spectrum of the thermally unstable, electrogenerated RuIII-ethene cation 6+ has been observed at −50 °C. Cyclic voltammetry of the μ-dinitrogen complex 10 shows two, fully reversible processes in CH2Cl2 at −50 °C at +0.30 and +0.90 V (versus Ag/AgCl) corresponding to the formation of 10+ (RuII,III) and 102+ (RuIII,III). The former, generated electrochemically at −50 °C, shows a band in the near IR at ca. 8900 cm−1 (w1/2 ca. 3700 cm−1) consistent with the presence of a valence delocalized system. The comproportionation constant for the equilibrium 10 + 102+ ? 2 10+ at 223 K is estimated as 1013.6.  相似文献   

16.
The synthesis of iron(II), cobalt(II) and nickel(II) complexes supported by chelating borate ligands containing one pyrazole and two thioethers, phenyl(pyrazolyl)bis((alkylthio)methyl)borates, [Ph(pz)BtR], is described. The six-coordinate complexes [Ph(pz)Bt]2M, M = Fe (1Fe), Co (1Co) and Ni (1Ni), form exclusively the cis isomers as confirmed by X-ray diffraction analyses. Whereas 1Co and 1Ni are high spin, 1Fe exhibits a room temperature magnetic moment, μeff = 4.1 μB, consistent with spin-crossover behavior. Quantitative analysis of the electronic spectrum of 2Ni leads to a value of Dq = 1086 cm−1, reflective of a ligand field strength somewhat weaker than those imposed by the related tridentate borate ligands Tp or PhTt. Replacement of the methylthioether substituent with the sterically more demanding tert-butylthioether leads to the isolation of [Ph(pz)BttBu]MX, M = Co, X = Cl (2Co); M = Ni, X = Cl (2Ni) or acac (3). The solid state structures of 2Co and 2Ni are chloride-bridged dimers. Additional high-spin cobalt(II) complexes, accessible under distinct preparative conditions, [κ2-Ph(pzH)BttBu] CoCl2·THF (4) and [κ2-Ph(pz)BttBu]2Co (5), have been fully characterized.  相似文献   

17.
Preparations, XPS and electronic spectroscopy, and magnetism of seven new one-dimensional cyano-bridged coordination polymers, chiral [Cu(RR-chxn)2][Pd(CN)4] · 2H2O (1), [Cu(trans-chxn)2][M(CN)4] · 2H2O (2, 4, and 6 for M = Pd, Ni, and Pt), and [Cu(cis-chxn)2][M(CN)4] · 2H2O (3, 5, and 7 for M = Pd, Ni, and Pt) (RR-chxn = cyclohexane-(1R,2R)-diamine, trans-chxn = racemic trans-cyclohexane-(1,2)-diamine, and cis-chxn = racemic cis-cyclohexane-(1,2)-diamine) have been reported in view of tuning of their electronic properties by stereochemistry of chxn ligands and metal-substitution. Comparison of Cu 2p1/2 and 2p3/2 peaks of XPS and broad d-d bands around 18 000 cm−1 of electronic spectra are described systematically for 1-7. Variable-temperature magnetic measurement shows that complexes 1-7 indicate weak antiferromagnetic interactions via cyano-bridges. Because of semi-coordination coupled with pseudo Jahn-Teller elongation and electrostatic interaction for 1, the axial Cu-N coordination bond distances of 2.330(7) and 3.092(8) Å are considerably longer than those of equatorial ones in the range from 2.016(6) to 2.030(6) Å. The former bond distances of 1 are intermediate values among the related Ni (2.324(6) and 3.120(8) Å) and Pt (2.34(1) and 3.09(1) Å) complexes.  相似文献   

18.
Based on self-assembly of the dissymmetrical mononuclear entity CuL(CH3OH) [H2L = (E)-N1-(2-((2-aminocyclohexydiimino)(phenyl)methyl)-4-chlorophenyl)-N2-(2-benzyl-4-chlorophenyl)oxalamide] with Mn(II), two trinuclear complexes were prepared. They are of the formula [(LCuN3)2Mn(CH3OH)2] · 2CH3OH · 2H2O (1) and [(LCuSCN)2Mn(H2O)2] · 4CH3OH (2). Their magnetic properties were studied by susceptibility versus temperature measurement, the best fitting of the experimental data led to J = −14.40 cm−1 for 1 and J = −15.48 cm−1 for 2. Hydrogen bonds help complex 1 to produce a novel S type one-dimensional chain-like supramolecular structure. In complex 2, Cl?Cl interaction also results in the formation of a one-dimensional structure.  相似文献   

19.
The reaction of [Rh2(acam)4(H2O)2]ClO4 (1) (Hacam = acetamide) with K2PtCl4 in aqueous solution gave crystals of [Rh2(acam)4(H2O)2][Rh2(acam)4{(μ-Cl)2PtCl2}] · 2H2O (2). The reaction of 1 with K2PdCl4 produced the palladium analog [Rh2(acam)4(H2O)2][Rh2(acam)4{(μ-Cl)2PdCl2}] · 2H2O (3) and a small amount of an aquated palladium complex [Rh2(acam)4{(μ-Cl)2PdCl(H2O)}] · H2O (4). Complexes 2 and 3 have anionic chains of [Rh2(acam)4{(μ-Cl)2MCl2}] (M = Pt, Pd), while 4 includes neutral chains of [Rh2(acam)4{(μ-Cl)2PdCl(H2O)}]. Although all of the structures include infinite chains of (-Rh-Rh-Cl-M-Cl-)n (M = Pt, Pd), the chain structures are different; zigzag for 2 and 3 and helical for 4. In the structures of 2 and 3, the counter cation [Rh2(acam)4(H2O)2]+ made a hydrogen-bonded chain with the crystallization water molecules. The cationic chains and the anionic chains are connected with hydrogen bonds. In the structure of 4, the chains are also linked together by direct hydrogen bonds between the chains and those with the crystallization water molecules. ESR spectra of the powdered samples of 2 and 3 at 77 K were consistent with a rhombic structure: for 2, g1 = 2.111, g2 = 2.054, g3 = 2.004; for 3, g1 = 2.115, g2 = 2.057, g3 = 2.007. These results indicate that there is a spin flip-flop exchange between the cations, [Rh2(acam)4(H2O)2]+, and the units in the anionic chains. The electrical conductivities of 2 and 3 were in the order of 10−7 S cm−1 at room temperature.  相似文献   

20.
To investigate the influence of temperature and the ratios of solvents on the design and synthesis of metal-organic frameworks (MOFs), we have synthesized and structurally characterized a series of supramolecular assemblies based on different amino acid derivatives and nitrogen-containing heterocyclic ligands, namely [Mn(phen)2(phth)(H2O)]·4H2O (1), [Mn(phen)2(HL1)2]·3.5H2O (2), [Zn(bpp)2(L-Me)2] (3), and [Zn(bpp)(L-Me)2] (4) (H2phth = phthalic acid, H2L1 = phthalyl-l-valine, H2L = (+)-N-tosyl-l-glutamic acid, phen = 1,10-phenanthroline, bpp = 1,3-bis(4-pyridyl)propane, and L-Me = C12H13NO6S-CH3). Compounds 1 and 2, which are assembled through noncovalent interactions, were obtained by controlling the temperature. In 1, π-π stacking and hydrogen-bonding interactions lead to stacking in a 3D supramolecular network, while in 2, π-π stacking interactions form 1D chains that extend along the c-axis. Depending on the solvents employed, compounds 3 and 4 could be generated, with a 1D bpp-connected Zn-bpp-Zn double chain that is further hydrogen-bonded into a 2D network that extends parallel to the ac plane in 3, and a single chain in 4.  相似文献   

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