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1.
Mercury(II) halide complexes [HgX2(P(2-py)3)2] (X?=?Br (1), Cl (2)) and [HgX2(PPh(2-py)2)2] (X?=?Br (3), Cl (4)) containing P(2-py)3 and PPh(2-py)2 ligands (P(2-py)3 is tris(2-pyridyl)phosphine and PPh(2-py)2 is bis(2-pyridyl)phenylphosphine) were synthesized in nearly quantitative yield by reaction of corresponding mercury(II) halide and appropriate ligands. The synthesized complexes are fully characterized by elemental analysis, melting point determination, IR, 1H, and 31P-NMR spectroscopies. Furthermore, the crystal structure of [HgBr2(PPh(2-py)2)2] determined by X-ray diffraction is also reported.  相似文献   

2.
Two new dibenzyltin bisditiocarbamates(PhCH2)2 Sn(S2CNEt2)2(1) and (PhCH2)2 Sn(S2CNC4H8)2(2) were synthesized by the reaction of dibenzyltin dichloride with dithiocarbamates and characterized by elemental analysis ,IR,^1H NMR and MS spectra.The crystal structures were determined by X-ray single crystal diffraction analysis.In both complexes,the tin atom is six-coordinated in a distorted octahedral configuration.In the crystals of 1,the molecular packing in unit cell reveals that the two adjacent molecules are symmetrically linked to each other in dimers by two Sn S interactions of 0.3816nm.In the crystals of 2,the molecules are packed in the unit cell in one-dimensional chain structure linked by weaker intermolecular S S conmtacts.  相似文献   

3.
1 INTRODUCTION Schiff’s bases are well known ligands representedby many bi-, tri-, tetra-, and hexa-dentate example-es[1], but heptadentate ligands are relatively rare[2, . 3]We have reported a copper complex of tetradentateSchiff’s bases[4]…  相似文献   

4.
Jian  Fangfang  Wang  Zuoxiang  Bai  Zhiping  You  Xiaozeng  Chen  Wei 《Transition Metal Chemistry》1999,24(5):589-594
Two modifications of the and forms of bis(imidazole)copper(II) dibenzoate, [Cu(im)2(OBz)2], have been obtained by recrystallization from EtOH. X-ray analysis reveals that the two modifications have the same structure with different geometric parameters. The form crystallizes in the C2/c space group and the form, in the P2(1)/n space group. The crystal structures of both consist of centrosymmetric monomeric molecules of [Cu(im)2(OBz)2] with a distorted octahedral geometry for the CuN2O2O2 chromophore. The e.s.r. spectra of the and forms exhibit a shf structure that consists of 9 lines, and these signals are also different from those of monomeric tetra(imidazole)copper(II) diacetate. Electronic and i.r. spectra are in agreement with the structural data.  相似文献   

5.
The i.r. and Raman spectra of CuCl2·2H2O and K2CuCl4·2H2O and of deuterated samples of these compounds are presented in the range 50–1700 cm−1 at liquid helium, liquid nitrogen, and ambient temperatures. The spectra obtained are discussed and compared with the literature data in terms of both bonding structure of the water molecules and vibrational modes, assignment, intermolecular coupling, and combination bands of the H2O, HDO, and D2O librations. The i.r. and Raman bands of the librational modes of CuCl2·2H2O are very broad even at liquid helium temperature indicating orientational disorder of the water molecules.  相似文献   

6.
Thioselenohalide complexes Mo2(μ-S2)2Cl6(SeCl2)2 (I), Mo2(μ-S2)2Br6(SeBr2)2 (II), and W2(μ-S2)2Br6(SeBr2)2 (III) were synthesized by the reactions of corresponding metal halides or carbonyls or molybdenum metal with excesses of S2 X 2+Se2 X 2 mixtures. The complex W2(μ-S2)2Cl6(SeCl2)2 (IV) was obtained by an exchange reaction between (III) and excess of Se2Cl2. Coordination of the neutral SeX 2 ligands to thiohalidesM 2(μ-S2)2 X 6 results in higher thermal stability, and suggests the possibility to synthesize SeX 2 complexes of the unstable parent tungsten thiohalides. An unusual oxidative addition reaction of (I) was detected: {fx27-1} Both (I) and (IV) were characterized by X-ray crystal structure analysis. They are isostructural and form discrete molecules. Bridging S 2 2? ligands are coordinated perpendicularly to the metal-metal bond;d(M?M)=2.8066 Å and 2.793 Å for I and IV, respectively. Nonequivalence of chlorine atoms which are bound to the metal atom, relate to nonequivalence of halogen atoms in the complexesM 2(μ?S2)2 X 8 2? . Chlorine atomstrans to SeCl2 ligands form short bonds with the metal; the corresponding35Cl NQR frequency is increased. The selenium dichloride ligand is ambidentate. The selenium atom binds as a donor to the metal and as an acceptor to two chlorine atoms which are also bound covalently to the same metal atom.  相似文献   

7.
Three pyridylbenzimidazoles (2-PBIM, 3-PBIM, and 4-PBIM) have been prepared (2-PBIM: 2-(2-pyridyl)-benzimidazole, 3-PBIM: 2-(3-pyridyl)-benzimidazole, 4-PBIM: 2-(4-pyridyl)-benzimidazole). Reactions of several transition metals (Cd2+, Cu2+, Fe2+) with the three ligands gave four new coordination complexes, [(Cd)2(2-PBIM)2(CH3COO)4] (1), [Cu(3-PBIM)2(CH3COO)2]?·?2H2O (2), [Cu(4-PBIM)2(CH3COO)2(H2O)]?·?H2O (3), and [Fe(4-PBIM)2(Cl)2(H2O)2] (4), respectively. These four complexes have been characterized by X-ray crystallography, IR spectroscopy, and UV absorption spectroscopy. Thermogravimetric properties of 2 and 4 were also measured. X-ray crystallographic studies reveal that these four complexes are very different, although the ligands are similar in structure. The role of hydrogen-bonding and π–π interactions in extending dimensionality of simple complexes has been discussed.  相似文献   

8.
Treatment of [Cy2P(CH2OH)2]Cl with MeNH2 in the presence of Et3N affords a high yield of the phosphine (Cy2PCH2)2NMe (1) (dcpam) which has been characterised by a single crystal X-ray structure. Treatment of [PtX2(COD)], (COD=cyclo-octa-1,5-diene, X= Cl or I) with (1) affords the platinum complexes [PtX2{(Cy2PCH2)2NMe}] (2). The chloride complex, (2a), reacts with t-BuNC to afford [PtCl(t-BuNC)-{(Cy2PCH2)2NMe}]Cl (3) and treatment of (2a) with 2-mercapto-1-methylimidazole affords [Pt{SCN(Me)CHCH=N(Me)}{Cy2PCH2)2NMe}]Cl (5). The reaction of (2a) with 2-acetamidoacrylic acid in the presence of silver(I) oxide affords the carbon bonded isomer (8a) only whereas a similar reaction using [PtCl2{Ph2P-(CH2)3PPh2}] affords a mixture of the azaallyl complex (7) and the carbon bonded isomer (8b) which can be separated by fractional crystallisation. The crystal structures of PtX2{(Cy2PCH2)2NMe}] are also reported.  相似文献   

9.
The preparation and characterization of a new gallium(III) complex with quinoline-2-carboxylate, of formula [Ga(quin-2-c)2Cl], are described. The crystal structure of the complex has been determined by X-ray diffraction, crystallizing in monoclinic space group P21/n with Ga(III) adopting a distorted tetragonal pyramid. Gallium(III) coordinates two quinoline-2-carboxylates and one chloride with a Cl,N2,O2 donor set. In the crystal the 2-D supramolecular structure is generated by weak intermolecular interactions, C–H?···?O, C–H?···?Cl, and C–H?···?π. The cytotoxicity assays against several human cancer cell lines (Du145, A549, MCF-7, A498, HT-29) and against mouse fibroblasts (BALB/3T3) revealed moderate antiproliferative activity of the complex.  相似文献   

10.
Silyleneisthesimilarityofsilicontocarbene,and,likecarbeneinorganicreactions,itplaysaveryimportantroleinorganosiliconreactions.Inrecentyears,therehavebeenmanyreportsonsilylenesinquantumchemicalresearches[1—3].Investigationonitsorganicreactionshowsthatreali…  相似文献   

11.

A series of new complexes of the Schiff base obtained from trans- cinnamaldehyde and 1,2-diaminoethane (en) with the general formula of M(ca 2 en)X 2 (M = Co(II), Ni(II), Zn(II); X = Cl, Br, I, NCS, N 3 ; (ca 2 en) = N,N '-bis( trans- cinnamaldehyde)-1,2-diiminoethane) have been synthesized and characterized. The crystal structures of three pseudo -tetrahedral complexes, Co(ca 2 en)Cl 2 ( 1 ), Co(ca 2 en)Br 2 ( 2 ), and Ni(ca 2 en)Br 2 ( 5 ), were determined by X-ray diffraction. Crystal data for 1 , Co(ca 2 en)Cl 2 : monoclinic; space group P 2 1 / c ; a = 7.1925(14) Å, b = 20.327(4) Å, c = 14.029(3) Å; g =95.06(3)°; V = 2043.1(7) Å 3 ; Z = 4; and final R 1 = 0.0381 ( wR 2 = 0.0718) for 4653 independent reflections with I > 2 σ ( I ) and 226 parameters; 2 , Co(ca 2 en)Br 2 ; monoclinic, space group P 2 1 / c ; a = 7.3780(6) Å, b = 20.4372(17) Å, c = 14.1649(12) Å; g = 94.902(2)°; V = 2128.1(3) Å 3 ; Z = 4; and final R 1 = 0.0491 ( wR 2 = 0.1052) for 5858 independent reflections with I > 2 σ ( I ) and 227 parameters; 5 , Ni(ca 2 en)Br 2 : monoclinic, space group P 2 1 / c ; a = 7.2388(6) Å, b = 20.4651(16) Å, c = 14.2782(12) Å; g = 94.160(2)°; V = 2109.6(3) Å 3 ; Z = 4; R 1 = 0.0481 ( wR 2 = 0.0907) for 5914 independent reflections with I > 2 σ ( I ) and 227 parameters. The structures consist of discrete molecules in which the coordination polyhedra about the central metal ion are highly distorted tetrahedra with Cl(1)-Co-Cl(2), 115.51(3)°; N(1)-Co-N(2), 83.71(7)°; Br(1)-Co-Br(2), 114.58(4)°; N(1)-Co-N(2), 84.92(19)°; and Br(1)-Ni-Br(2), 125.23(3)°; N(1)-Ni-N(2), 85.11(15)° in 1 , 2 , and 5 , respectively. The stiryl groups are cis -endo with respect to the metal atom and the chelate ring is puckered. Utilization is made of electronic and vibrational spectra in structural diagnosis of other complexes.  相似文献   

12.
A new dinuclear complex, [Ag(L)(CH3CN)]2(C1O4)2·2H2O(L=2,3-di-2-pyridylquinoxaline), was prepared and characterized by elemental analyses,IR spectroscopy, and single-crystal X-ray diffraction analyses. The interaction of the complex with calf thymus DNA(CT-DNA) was investigated by absorption, fluorescence spectroscopies, and viscosity measurement. The results suggested that the complex was bound to DNA via an intercalative mode. The intrinsic binding constant value Kb was found to be approximately 1.48×103 L·mol-1. Moreover, the Ag(Ⅰ) complex could cleave the plasmid pUC19 DNA from the supercoiled Form I to the nicked Form Ⅱ under irradiation at 365 nm.  相似文献   

13.
Two novel complexes, [Cd2(BMQU)2Cl4] (1) and [Ni(BMQU)2HPO4]·1.5H2O (2) (BMQU = 2-(2-benzimidazolyl)quinoline), were synthesized by the hydrothermal method and characterized by elemental analysis, IR, and TG-DTG. The crystal structures were determined by single-crystal X-ray diffraction. Both 1 and 2 crystallize in the triclinic system, space group P . The data for 1: a = 0.8342(7), b = 0.9226(9), c = 1.0646(8) nm, α = 90.819(2), β = 97.466(2), γ = 98.280(2)°. The Cd(Ⅱ) is coordinated with three chlorine atoms and two nitrogen atoms of a BMQU molecule, generating a distorted square-pyramidal geometry. The dinuclear Cd(Ⅱ) complex is formed by two chlorine bridge bonds, and the one-dimensional chain structure is constructed with the hydrogen bond N-H…Cl and π-π stacking interaction. The data for 2: a = 1.2251(1), b = 1.2451(1), c = 1.2868(1) nm, α = 107.510(2), β = 98.630(1), γ = 109.921(2)°. The Ni(Ⅱ) is coordinated with four nitrogen atoms of two BMQU molecules and two oxygen atoms of a HPO42-, forming a distorted-octahedral geometry. The two-dimensional layer structure is formed by the hydrogen bonds and π-π stacking interaction between neighboring molecules. Complex 1 shows a strong blue fluorescence emission (λmax= 456 nm) at solid state.  相似文献   

14.
《Polyhedron》1999,18(26):3497-3504
The addition of pinacol to mixtures of titanium and cerium isopropoxides as well as the use of insoluble titanium and cerium pinacolate synthons was investigated as a route to M-Ce (M=Ti, Nb) species. Pinacol was able to promote the formation of mixed-metal species and the first Ce-Ti and Ce-Nb species namely Ce2Ti(pin)2(OPri)8 and [M2Ce23-O)2(μ,η2pin)4(OPri)6Hx] [M=Ti, x=2; M=Nb, x=0; pin=OCMe2-COMe2] were isolated and characterized by FT-IR and 1H NMR. The latter were also characterized by X-Ray diffraction. Their structures are based on a rhombus compressed along the M⋯M direction with 6-coordinated metals. The pinacolate moieties act as bridging-chelating ligands. The metal–oxygen bond lengths vary according to M–O(pin)<M-μ3–O<Mμ–O(pin)<Ce–OPri<Ce–μ3O.  相似文献   

15.
The compound Ba4Fe2I5S4 has been prepared at 1223-1123 K by the "U-assisted" reaction of FeS, BaS, S, and U with BaI2 as a flux. A more rational synthesis was also found; however, the presence of U appears to be essential for the formation of single crystals suitable for X-ray diffraction studies. Ba4Fe2I5S4 crystallizes in a new structure type with two formula units in space group I4/m of the tetragonal system. The structure consists of a Ba-I network penetrated by (1)infinity[Fe2S4] chains. Each Fe atom, which is located on a site with 4 symmetry, is tetrahedrally coordinated to four S atoms. The FeS4 tetrahedra edge-share to form linear (1)infinity[Fe2S4] chains in the [001] direction. The Fe-Fe interatomic distance in these chains is 2.5630(4) A, only about 3% longer than the shortest Fe-Fe distance in -Fe metal. Charge balance dictates that the average formal oxidation state of Fe in these chains is +2.5. The M?ssbauer spectra obtained at 85 and 270 K comprise a single quadrupole doublet that has hyperfine parameters consistent with an average Fe oxidation state of +2.5. The M?ssbauer spectrum obtained at 4.2 K consists of a single magnetic sextet with a small hyperfine field of -15.5 T. This spectrum is also consistent with rapid electron delocalization and an average Fe oxidation state of +2.5. The molar magnetic susceptibility of Ba4Fe2I5S4, obtained between 3.4 and 300 K, qualitatively indicates the presence of weak pseudo-one-dimensional ferromagnetic exchange within a linear chain above 100 K and weak three-dimensional ordering between the chains at lower temperatures.  相似文献   

16.
《Tetrahedron: Asymmetry》1999,10(14):2665-2674
Reactions of (menthyl)PH2 and H2CCHRf6 (menthyl=1R,3R,4S; Rfn=(CF2)n−1CF3) or H2CCHRf8 (AIBN, refluxing THF) give (menthyl)PH(CH2CH2Rfn) and then (menthyl)P(CH2CH2Rfn)2 (n=6, 7; n=8, 8), but with purification or other difficulties at each stage. Reactions of (menthyl)PCl2 with IMgCH2CH2Rfn give, under careful conditions, analytically pure 7 or 8 in 28–32% yields after distillation. Some Rfn(CH2)4Rfn also form. These represent the first chiral (and non-racemic) fluorous phosphines. Reactions of 7 or 8 with [Ir(COD)Cl]2 and CO give trans-[(menthyl)P(CH2CH2Rfn)2]2Ir(Cl)(CO) (n=6, 71%; 8, 51%) as analytically pure yellow oils. Their IR νCO values show the donor/acceptor properties of 7 and 8 to be intermediate between those of P((CH2)3Rf8)3 and P((CH2)4Rf8)3. The CF3C6F11:toluene partition coefficients of 7 and 8 (27°C, 78.4:21.6 and 93.7:6.3) are distinctly lower than those of P((CH2)2Rfn)3 (n=6, 98.8:1.2; n=8, >99.7:<0.3), reflecting the replacement of a linear C8–C10 group that is ca. 75–80% fluorinated by a cyclic C10 terpenyl group. Reactions of 7 or 8 with [Rh(COD)Cl]2 give [(menthyl)P(CH2CH2Rfn)2]Rh(Cl)(COD) (n=6, 69%; 8, 70%) as orange crystallizable oils.  相似文献   

17.
Two bis(saccharinato)copper(II) complexes with 2-aminomethylpyridine (ampy) and 2-aminoethylpyridine (aepy) have been prepared and characterized by elemental analyses, IR and electronic spectroscopy, magnetic measurements and single-crystal X-ray diffraction. The copper(II) ion in trans-[Cu(sac)2(ampy)2] has ?1 site symmetry and is octahedrally coordinated by two neutral ampy and two anionic sac ligands, whereas the copper(II) ion in [Cu(sac)2(aepy)(H2O)] is five-coordinate with a distorted square-pyramidal coordination geometry. Both ampy and aepy behave as bidentate (N,N′) chelating ligands, while the saccharinate anion (sac) in the title complexes is N-coordinated. IR spectra of both complexes display typical absorption bands of bidentate aminopyridines and N-bonded sac ligands. Thermal decomposition behavior of the complexes is described in detail.  相似文献   

18.
Quantum chemical calculations using DFT (BP86) and ab initio methods (MP2, MP4 and CCSD(T)) have been carried out for the title compounds. The nature of the Pb?CPb interactions has been investigated with an energy decomposition analysis. The energy minimum structures of the halogen substituted Pb2X2 molecules possess a doubly bridged butterfly geometry A like the parent system Pb2H2. The unusual geometry can be explained with the interactions between PbX fragments in the X 2?? ground state which leads to one Pb?CPb electron-sharing ?? bond and two donor?Cacceptor bonds between the Pb?CX bonds as donor and vacant p(??) AOs of Pb. The energy difference between the equilibrium form A and the linear structure XPb??PbX (E) which is a second-order saddle point is much higher when X is a halogen atom than for X?=?H. This is because the a 4???????X 2?? excitation energies of PbX (X?=?F?CI) are higher than for PbH. The structural isomers B, D1, D2, E, F1, F2 and G of Pb2X2 are no minima on the potential energy surface.  相似文献   

19.
《European Polymer Journal》1986,22(4):293-298
Synthesis and optical resolution of 3-ethyl-3-phenylazetidinone-2 were improved to obtain (RS)-, (R)- and (S)-monomers having optical purities up to 98%, which could successfully be determined by 1H-NMR 250 MHz using tris[3-(2,2,2-trifluoro-l-hydroxymethylidene)d-camphorato]europium III as a shift reagent. These monomers were polymerized anionically in HMPT using potassium salt as a catalyst and by the addition of 1-acetyl-4,4-dimethylazetidinone-2 as a chain initiator. Optical purity of the starting monomer seemed to be maintained in the resulting polymers, the thermal properties of which were found to depend on the mean length of the stereoblocks contained in the chain. While the reactivity, in particular the case of polymerization, of monomer increased with the optical purity, no evidence could be obtained for stereoregulation by a preferential incorporation of a monomer enantiomer according to the configuration of the growing chain end unit.  相似文献   

20.
Rotationally resolved absorption spectra of I(2) (+) were recorded in 12 065-13 062 cm(-1) region by employing optical heterodyne velocity modulation absorption spectroscopy. In total, 4054 lines were assigned to 24 bands in the A(2)Π(3∕2,u)-X(2)Π(3∕2,g) system spanning the vibrational levels υ(') = 1-4 and υ(n) (') = 11-19. The assigned lines were globally fitted and an error of 0.003 cm(-1) was obtained. Rotational constants, B(υ), were used to derive equilibrium parameters B(e) (') = 0.03977725(77) cm(-1), a(e) (') = 1.1819(24)×10(-4) cm(-1), r(e) (') = 2.584386(25) A? of the X(2)Π(3∕2,g) state, and B(e) (') = 0.0305787(37) cm(-1), a(e) (') = 1.2353(23)×10(-4) cm(-1), r(e) (') = 2.94758(18) A? of the A(2)Π(3∕2,u) state. Vibrational energies were used to derive ω(e) (') = 239.0397(55) cm(-1), ω(e)x(e) (') = 0.64951(87) cm(-1) of the X(2)Π(3∕2,g) state and ω(e) (') = 138.103(11) cm(-1), ω(e)x(e) (') = 0.45027(34) cm(-1) of the A(2)Π(3∕2,u) state. The A(2)Π(3∕2,u) (υ(n) = 13) state was found to be rotationally perturbed by the a(4)Σ(1/2,u) (-) (υ(n) = 17) state through second-order spin-orbit coupling.  相似文献   

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