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1.
Ten copper(II) complexes {[CuL1Cl] (1), [CuL1NO3]2 (2), [CuL1N3]2 · 2/3H2O (3), [CuL1]2(ClO4)2 · 2H2O (4), [CuL2Cl]2 (5), [CuL2N3] (6), [Cu(HL2)SO4]2 · 4H2O (7), [Cu(HL2)2] (ClO4)2 · 1/2EtOH (8), [CuL3Cl]2 (9), [CuL3NCS] · 1/2H2O (10)} of three NNS donor thiosemicarbazone ligands {pyridine-2-carbaldehyde-N(4)-p-methoxyphenyl thiosemicarbazone [HL1], pyridine-2-carbaldehyde-N(4)-2-phenethyl thiosemicarbazone [HL2] and pyridine-2-carbaldehyde N(4)-(methyl), N(4)-(phenyl) thiosemicarbazone [HL3]} were synthesized and physico-chemically characterized. The crystal structure of compound 9 has been determined by X-ray diffraction studies and is found that the dimer consists of two square pyramidal Cu(II) centers linked by two chlorine atoms.  相似文献   

2.
Ni(II) complexes (15) of di-2-pyridyl ketone N(4)-phenylthiosemicarbazone (HL) have been synthesized and spectrochemically characterized. Elemental analyses revealed a NiL2 · 2H2O stoichiometry for compound 1. However, the single crystals isolated revealed a composition NiL2 · 0.5(H2O)0.5(DMF). The compound crystallizes into a monoclinic lattice with the space group P21/n. Complexes 2, 3 and 4 are observed to show a 1:1:1 ratio of metal:thiosemicarbazone:gegenion, with the general formula NiLX · yH2O [X = NCS, y = 2 for 2; X = Cl, y = 3 for 3 and X = N3, y = 4.5 for 4]. Compound 5 is a dimer with a metal:thiosemicarbazone:gegenion ratio of 2:2:1, with the formula [Ni2L2(SO4)] · 4H2O.  相似文献   

3.
4.
N-thioamide thiosemicarbazone derived from 4-(methylthio)benzaldehyde (R = H, HL1; R = Me, HL2 and R = Ph, HL3) have been prepared and their reaction with fac-[ReX(CO)3(CH3CN)2] (X = Br, Cl) in methanol gave the adducts [ReX(CO)3(HLn)] (1a X = Cl, n = 1; 1a′ X = Br, n = 1; 1b X = Cl, n = 2; 1b′ X = Br, n = 2; 1c X = Cl, n = 3; 1c′ X = Br, n = 3) in good yield.All the compounds have been characterized by elemental analysis, mass spectrometry (ESI), IR and 1H NMR spectroscopic methods. Moreover, the structures of HL2, HL3, HL3·(CH3)2SO and 1b′·H2O were also elucidated by X-ray diffraction. In 1b′, the rhenium atom is coordinated by the sulphur and the azomethine nitrogen atoms (κS,N3) forming a five-membered chelate ring, as well as three carbonyl and bromide ligands. The resulting coordination polyhedron can be described as a distorted octahedron.The structure of the dimers is based on rhenium(I) thiosemicarbazonates [Re2(L1)2(CO)6] (2a), [Re2(L2)2(CO)6] (2b) and [Re2(L3)2(CO)6] (2c) as determined by X-ray studies. Methods of synthesis were optimized to obtain amounts of these thiosemicarbazonate complexes. In these compounds the dimer structures are achieved by Re-S-Re bridges, where S is the thiolate sulphur from a κS,N3-bidentate thiosemicarbazonate ligand.Some single crystals isolated in the synthesis of 2b contain [Re(L4)(L2)(CO)3] (3b) where L4 (=2-methylamine-5-(para-methylsulfanephenyl)-1,3,4-thiadiazole) is originated in a cyclization process of the thiosemicarbazone. Furthermore, the rhenium atom is coordinate by the sulphur and the thioamidic nitrogen of the thiosemicarbazonate (κS,N2) affording a four-membered chelate ring.  相似文献   

5.
The reactions of Mo2(O2CCH3)4 with different equivalents of N,N′-bis(pyrimidine-2-yl)formamidine (HL1) and N-(2-pyrimidinyl)formamide (HL2) afforded dimolybdenum complexes of the types Mo2(O2CCH3)(L1)2(L2) (1) trans-Mo2(L1)2(L2)2 (2) cis-Mo2(L1)2(L2)2 (3) and Mo2(L2)4 (4). Their UV–Vis and NMR spectra have been recorded and their structures determined by X-ray crystallography. Complexes 2 and 3 establish the first pair of trans and cis forms of dimolybdenum complexes containing formamidinate ligands. The L1 ligands in 13 are bridged to the metal centers through two central amine nitrogen atoms, while the L2 ligands in 14 are bridged to the metal centers via one pyrimidyl nitrogen atom and the amine nitrogen atom. The Mo–Mo distances of complexes 1 [2.0951(17) Å], 2 [2.103(1) Å] and 3 [2.1017(3) Å], which contain both Mo?N and Mo?O axial interactions, are slightly longer than those of complex 4 [2.0826(12)–2.0866(10) Å] which has only Mo?O interactions.  相似文献   

6.
MgMe2 (1) was found to react with 1,4-diazabicyclo[2.2.2]octane (dabco) in tetrahydrofuran (thf) yielding a binuclear complex [{MgMe2(thf)}2(μ-dabco)] (2). Furthermore, from reactions of MgMeBr with diglyme (diethylene glycol dimethyl ether), NEt3, and tmeda (N,N,N′,N′-tetramethylethylenediamine) in etheral solvents compounds MgMeBr(L), (L = diglyme (5); NEt3 (6); tmeda (7)) were obtained as highly air- and moisture-sensitive white powders. From a thf solution of 7 crystals of [MgMeBr(thf)(tmeda)] (8) were obtained. Reactions of MgMeBr with pmdta (N,N,N′,N″,N″-pentamethyldiethylenetriamine) in thf resulted in formation of [MgMeBr(pmdta)] (9) in nearly quantitative yield. On the other hand, the same reaction in diethyl ether gave MgMeBr(pmdta) · MgBr2(pmdta) (10) and [{MgMe2(pmdta)}7{MgMeBr(pmdta)}] (11) in 24% and 2% yield, respectively, as well as [MgMe2(pmdta)] (12) as colorless needle-like crystals in about 26% yield. The synthesized methylmagnesium compounds were characterized by microanalysis and 1H and 13C NMR spectroscopy. The coordination-induced shifts of the 1H and 13C nuclei of the ligands are small; the largest ones were found in the tmeda and pmdta complexes. Single-crystal X-ray diffraction analyses revealed in 2 a tetrahedral environment of the Mg atoms with a bridging dabco ligand and in 8 a trigonal-bipyramidal coordination of the Mg atom. The single-crystal X-ray diffraction analyses of [MgMe2(pmdta)] (12) and [MgBr2(pmdta)] (13) showed them to be monomeric with five-coordinate Mg atoms. The square-pyramidal coordination polyhedra are built up of three N and two C atoms in 12 and three N and two Br atoms in 13. The apical positions are occupied by methyl and bromo ligands, respectively. Temperature-dependent 1H NMR spectroscopic measurements (from 27 to −80 °C) of methylmagnesium bromide complexes MgMeBr(L) (L = thf (4); diglyme (5); NEt3 (6); tmeda (7)) in thf-d8 solutions indicated that the deeper the temperature the more the Schlenk equilibria are shifted to the dimethylmagnesium/dibromomagnesium species. Furthermore, at −80 °C the dimethylmagnesium compounds are predominant in the solutions of Grignard compounds 4-6 whereas in the case of the tmeda complex7 the equilibrium constant was roughly estimated to be 0.25. In contrast, [MgMeBr(pmdta)] (9) in thf-d8 revealed no dismutation into [MgMe2(pmdta)] (12) and [MgBr2(pmdta)] (13) even up to −100 °C. In accordance with this unexpected behavior, 1:1 mixtures of 12 and 13 were found to react in thf at room temperature yielding quantitatively the corresponding Grignard compound 9. Moreover, the structures of [MgMeBr(pmdta)] (9c), [MgMe2(pmdta)] (12c), and [MgBr2(pmdta)] (13c) were calculated on the DFT level of theory. The calculated structures 12c and 13c are in a good agreement with the experimentally observed structures 12 and 13. The equilibrium constant of the Schlenk equilibrium (2 9c ? 12c + 13c) was calculated to be Kgas = 2.0 × 10−3 (298 K) in the gas phase. Considering the solvent effects of both thf and diethyl ether using a polarized continuum model (PCM) the corresponding equilibrium constants were calculated to be Kthf = 1.2 × 10−3 and Kether = 3.2 × 10−3 (298 K), respectively.  相似文献   

7.
Three mononuclear cis-dioxovanadium(V) complexes of tridentate thiosemicarbazones derived from 5-methyl-3-formylpyrazole (MPA) and N(4)-methyl/ethyl/dimethyl thiosemicarbazide have been synthesized and characterized. Single crystal X-ray analyses were performed with [VO2L1] (1), [VO2L2] (2) and [VO2L3] (3), where L1, L2 and L3 denote the [1 + 1] thiosemicarbazone mono-anions derived from MPA and N(4)-substituted methyl/ethyl/dimethyl thiosemicarbazide respectively. In all the complexes the vanadium atom is in a distorted square pyramidal geometry with a N2SO2 chromophore. The interesting finding in the work is that in complexes 1 and 2, the thioimine nitrogen unusually participates in coordination whereas in 3 it is the azomethine nitrogen (quite usual) which is involved in the coordination process.  相似文献   

8.
The synthetic investigation of the CuII/maleamate(−1) ion (HL)/N,N′,N′′-chelate general reaction system has allowed access to compounds [Cu2(HL)2(bppy)2](ClO4)2·H2O (1·H2O), [Cu(HL)(bppy)(ClO4)] (2) and [Cu(HL)(terpy)(H2O)](ClO4) (4) (bppy = 2,6-bis(pyrazol-1-yl)pyridine, terpy = 2,2′;6′,2′′-terpyridine). In the absence of externally added hydroxides, compound [Cu2(L′)2(bppy)2](ClO4)2 (3) was obtained from MeOH solutions; L′ is the monomethyl maleate(−1) ligand which is formed in situ via the CuII-assisted HL → L′ transformation. In the case of tptz-containing (tptz = 2,4,6-tris(2-pyridyl)-1,3,5-triazine) reaction systems, the CuII-assisted hydrolysis of tptz to pyridine-2-carboxamide (L1) afforded complex [Cu(L1)2(NO3)2] (5). The crystal structures of 15 are stabilized by intermolecular hydrogen bonding and π–π stacking interactions. Characteristic IR bands of the complexes are discussed in terms of the known structures and the coordination modes of the ligands.  相似文献   

9.
N-Heterocyclic carbene ligands (NHC) were metalated with Pd(OAc)2 or [Ni(CH3CN)6](BF4)2 by in situ deprotonation of imidazolium salts to give the N-olefin functionalized biscarbene complexes [MX2(NHC)2] 3-7 (3: M = Pd, X = Br, NHC = 1,3-di(3-butenyl)imidazolin-2-ylidene; 4: M = Pd, X = Br, NHC = 1,3-di(4-pentenyl)imidazolin-2-ylidene; 5: M = Pd, X = I, NHC = 1,3-diallylimidazolin-2-ylidene; 6: M = Ni, X = I, NHC = 1,3-diallylimidazolin-2-ylidene; 7: M = Ni, X = I, NHC = 1-methyl-3-allylimidazolin-2-ylidene). Molecular structure determinations for 4-7 revealed that square-planar complexes with cis (5) or trans (4, 6, 7) coordination geometry at the metal center had been obtained. Reaction of nickelocene with imidazolium bromides afforded the η5-cyclopentadienyl (η5-Cp) monocarbene nickel complexes [NiBr(η5-Cp)(NHC)] 8 and 9 (8: NHC = 1-methyl-3-allylimidazolin-2-ylidene; 9: NHC = 1,3-diallylimidazolin-2-ylidene). The bromine abstraction in complexes 8 and 9 with silver tetrafluoroborate gave complexes [NiBr(η5-Cp)(η3-NHC)] 10 and 11. The X-ray structure analysis of 10 and 11 showed a trigonal-pyramidal coordination geometry at the nickel(II) center and coordination of one N-allyl substituent.  相似文献   

10.
Two structurally different complexes, [Cu2(2-NO2Bz)4(denia)1]n (1) and [Cu(2-NO2Bz)2(denia)2(H2O)2] (2), were prepared from the same reaction (where 2-NO2Bz = 2-nitrobenzoate, denia = N,N-diethylnicotinamide) and they are reported together with [Cu2(2-NO2Bz)4(DMF)2] (3) (DMF = N,N-dimethylformamide). The compounds under study were characterized by elemental analysis, electronic, IR and EPR spectra, magnetic measurements over the temperature range of 1.8–300 K and X-ray analysis. The molecular structure of (1) is polymeric, (2) is monomeric and (3) is dimeric. In the polymeric chain of (1), the denia molecules serve as bridges between dimeric Cu2(2-NO2bz)4 units. Each Cu(II) atom has a square-pyramidal arrangement with different chromophores, Cu1O4O′ and Cu2O4N. The Cu–Cu distances are 2.699(1) Å in the dimeric unit and 7.980(3) Å between the dimeric units. In (2) the Cu(II) atom has a tetragonal-bipyramidal environment CuO2N2O′2. In (3) two Cu(II) atoms are bridged by four carboxylate groups of four 2-NO2bz anions in a synsyn arrangement which create a square base about each Cu(II) atom and an apical position is occupied by the O atom of a DMF molecule (CuO4O′). The Cu–Cu distance of 2.633(1) Å is somewhat shorter than in (1). Spectral and magnetic data of the complexes are discussed with their structures.  相似文献   

11.
The syntheses and structures of a series of metal complexes, namely Cu2Cl4(L1)(DMSO)2·2DMSO (L1 = N,N′-bis(2-pyridinyl)-1,4-benzenedicarboxamide), 1; {[Cu(L2)1.5(DMF)2][ClO4]2·3DMF} (L2 = N,N′-bis(3-pyridinyl)-1,4-benzenedicarboxamide), 2; {[Cd(NO3)2(L3)]·2DMF} (L3 = N,N′-bis-(2-pyrimidinyl)-1,4-benzenedicarboxamide), 3; {[HgBr2(L3)]·H2O}, 4, and {[Na(L3)2][Hg2X5]·2DMF} (X = Br, 5; I, 6) are reported. All the complexes have been characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. Complex 1 is dinuclear and the molecules are interlinked through S?S interactions. In 2, the Cu(II) ions are linked through the L2 ligands to form 1-D ladder-like chains with 60-membered metallocycles, whereas complexes 3 and 4 form 1-D zigzag chains. In complexes 5 and 6, the Na(I) ions are linked by the L3 ligands to form 2-D layer structures in which the [Hg2X5] anions are in the cavities. The L2 ligand acts only as a bridging ligand, while L1 and L3 show both chelating and bridging bonding modes. The L1 ligand in 1 adopts a trans-anti conformation and the L2 ligand in 2 adopts both the cis-syn and trans-anti conformations, whereas the L3 ligands in 36 adopt the trans conformation.  相似文献   

12.
The reaction of boron heterocycles 1 and 2 with n-butyl lithium and alkyl halides led to (N→B) phenyl[N-alky-N-(2-alkyl)aminodiacetate-O,O′,N]boranes 36(ab), 7(b) and 9(b), where alkyl can be in exo and/or endo position, and phenyl[N-alkyl-N-(2-alkyl)aminodiacetate-O,O′,N]boranes 7(c) and 8(c) isomers, which do not display the intramolecular N→B coordination bond. The existence of steric interactions between N-benzyl and the alkyl group at 2 position was indicated by 1H and 13C NMR, while, the δ(11B) values confirm the tetrahedral and trigonal environment of the 11B nucleus in these compounds. Moreover, the compounds were characterized by COSY, HETCOR and homonuclear proton decoupling experiment. The study of the intramolecular N→B coordination by dynamic NMR afforded a ΔG‡ value of 81.09 kJ/mol for compound 6(b).  相似文献   

13.
For N-(thio)phosphorylthioureas of the common formula RC(S)NHP(X)(OiPr)2HLI (R = N-(4′-aminobenzo-15-crown-5), X = S), HLII (R = N-(4′-aminobenzo-15-crown-5), X = O), HLIII (R = PhNH, X = S), HLIV (R = PhNH, X = O), and (N,N′-bis-[C(S)NHP(S)(OiPr)2]2-1,10-diaza-18-crown-6) H2LV, salts LiLI,III,IV, NaLIIV, KLIIVM2LV (M = Li+, Na+, K+), Ba(LI,III,IV)2, and BaLV have been synthesized and investigated. Compounds NaLI,II quantitatively drop out as a deposit in ethanol medium, allowing the separation of Na+ and K+ cations. This effect is not displayed for the other compounds. The crystal structures of HLIII and the solvate of the composition [K(Me2CO)LIII] have been investigated by X-ray crystallography.  相似文献   

14.
15.
Four manganese(II) complexes of di-2-pyridyl ketone N(4)-methyl (HDpyMeTsc) and N(4)-ethyl thiosemicarbazones (HDpyETsc) were synthesized and physico-chemically characterized by means of partial elemental analyses, molar conductance measurements, electronic, infrared and EPR spectral studies. The complexes are represented as [Mn(DpyMeTsc)2] (1), [Mn(HDpyMeTsc)Cl2] (2), [Mn(HDpyMeTsc)2](ClO4)2 · H2O (3) and [Mn(DpyETsc)2] · 2H2O (4). The crystal structure of [Mn(DpyMeTsc)2] was established by single crystal X-ray diffraction studies. The compound crystallizes into a monoclinic lattice with P21/n space group. Manganese(II) exists in a distorted octahedral geometry in the complex.  相似文献   

16.
17.
The set of starting tri-, di- and monoorganotin(IV) halides containing N,C,N-chelating ligand (LNCN = {1,3-[(CH3)2NCH2]2C6H3}) has been prepared (1-5) and two compounds structurally characterized ([LNCNPh2Sn]+I3 (1c), LNCNSnBr3 (5)) in the solid state. These compounds were reacted with KF with 18-crown-6, NH4F or LCNnBu2SnF to give derivatives containing fluorine atom(s). Triorganotin(IV) fluorides LNCNMe2SnF (2a) and LNCNnBu2SnF (3a) revealed monomeric structural arrangement with covalent Sn-F bond both in the coordinating and non-coordinating solvents, except the behaviour of 3a that was ionized in the methanol solution at low temperature. The products of fluorination of LNCNSnPhCl2 (4) and 5 were described by NMR in solution as the ionic hypervalent fluorostannates or the oligomeric species reacting with chloroform, methanol or moisture to zwitterionic monomeric stannate LNCN(H)+SnF4 (5c), which was confirmed by XRD analysis in the solid state.  相似文献   

18.
Oxidation of N,N,N′,N′-tetrakis(diphenylphosphino)ethylendiamine (1) with elemental sulfur and selenium gives the corresponding sulfide and selenide, respectively, [(Ph2P(E))2NCH2CH2N(P(E)Ph2)2] (E: S 1a, Se 1b). Complexes of 1 [(M2Cl4){(Ph2P)2NCH2CH2N(PPh2)2}] (M: Ni(II) 1c, Pd(II) 1d, Pt(II) 1e) were prepared by the reaction of 1 with NiCl2 or [MCl2(COD)] (M = Pd, Pt). The new compounds were characterized by NMR, IR spectroscopy and elemental analysis. The catalytic activity of Pd(II) complex 1d was tested in the Suzuki coupling reaction and Heck reaction. The palladium complex 1d catalyses the Heck reaction between styrene and aryl bromides as well as Suzuki coupling reaction between phenylboronic acid and arylbromides affording stilbenes and biphenyls in high yield, respectively.  相似文献   

19.
The use of di-2-pyridyl ketone oxime, (py)pkoH, and phenyl 2-pyridyl ketone oxime, ppkoH, in copper(II) hexafluoroacetylacetonate chemistry is reported. The reaction of CuCl2·2H2O with one and two equivalents of ppkoH and Na(hfac), respectively, in CH2Cl2 affords the dinuclear complex [Cu2(hfac)2(ppko)2] (1) in excellent yield. The replacement of ppkoH by (py)pkoH gives the isostructural compound [Cu2(hfac)2{(py)pko}2] (2) in good yield. The CuII atoms in both 1 and 2 are doubly bridged by the oximate groups of two η1112 ppko and (py)pko ligands, respectively. The bridging Cu–(R–NO)–Cu′ units are not planar, with the torsion angles being 23.2° (1) and 20.3° (2). A bidentate chelating hfac ligand completes five-coordination at each square pyramidal metal ion. The hfac-free reaction system CuCl2·2H2O/(py)pkoH/NEt3 (1:2:1) gives instead the mononuclear complex [CuCl{(py)pko}{(py)pkoH}] (3) in very good yield. The CuII atom is coordinated by two N,N′-bidentate (py)pko/(py)pkoH chelates and a monodentate chloride anion resulting in a distorted square pyramidal geometry around the metal center. Variable-temperature, solid-state dc magnetic studies were carried out on the representative dinuclear complex 1 in the 2.0–300 K range. The data indicate a very strong antiferromagnetic exchange interaction and a resulting S = 0 ground state, which is well isolated from the S = 1 excited state. The J value of −720 cm−1 was derived from the fitting of the experimental data using the Hamiltonian H = −J(S1 · S2).  相似文献   

20.
The syntheses and crystal structures of four new uranyl complexes with [O,N,O,N′]-type ligands are described. The reaction between uranyl nitrate hexahydrate and the phenolic ligand [(N,N-bis(2-hydroxy-3,5-dimethylbenzyl)-N′,N′-dimethylethylenediamine)], H2L1 in a 1:2 molar ratio (M to L), yields a uranyl complex with the formula [UO2(HL1)(NO3)] · CH3CN (1). In the presence of a base (triethylamine, one mole per ligand mole) with the same molar ratio, the uranyl complex [UO2(HL1)2] (2) is formed. The reaction between uranyl nitrate hexahydrate and the ligand [(N,N-bis(2-hydroxy-3,5-di-t-butylbenzyl)-N′,N′-dimethylethylenediamine)], H2L2, yields a uranyl complex with the formula [UO2(HL2)(NO3)] · 2CH3CN (3) and the ligand [N-(2-pyridylmethyl)-N,N-bis(2-hydroxy-3,5-dimethylbenzyl)amine], H2L3, in the presence of a base yields a uranyl complex with the formula [UO2(HL3)2] · 2CH3CN (4). The molecular structures of 14 were verified by X-ray crystallography. The complexes 14 are zwitter ions with a neutral net charge. Compounds 1 and 3 are rare neutral mononuclear [UO2(HLn)(NO3)] complexes with the nitrate bonded in η2-fashion to the uranyl ion. Furthermore, the ability of the ligands H2L1–H2L4 to extract the uranyl ion from water to dichloromethane, and the selectivity of extraction with ligands H2L1, H3L5 (N,N-bis(2-hydroxy-3,5-dimethylbenzyl)-3-amino-1-propanol), H2L6 · HCl (N,N-bis(2-hydroxy-5-tert-butyl-3-methylbenzyl)-1-aminobutane · HCl) and H3L7 · HCl (N,N-bis(2-hydroxy-5-tert-butyl-3-methylbenzyl)-6-amino-1-hexanol · HCl) under varied chemical conditions were studied. As a result, the most efficient and selective ligand for uranyl ion extraction proved to be H3L7 · HCl.  相似文献   

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