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1.
New divalent transition metal 3,5-pyrazoledicarboxylate
hydrates of empirical formula Mpz(COO)2(H2O)2,
where M=Mn, Co, Ni, Cu, Zn and Cd (pz(COO)2=3,5-pyrazoledicarboxylate),
metal hydrazine complexes of the type Mpz(COO)2N2H4
where M=Co, Zn or Cd and Mpz(COO)2nN2H4·H2O,
where n=1 for M=Ni
and n=0.5 for M=Cu
have been prepared and characterized by physico-chemical methods. Electronic
spectroscopic data suggest that Co and Ni complexes adopt an octahedral geometry.
The IR spectra confirm the presence of unidentate carboxylate anion (Δν=νasy(COO–)–νsym(COO–)>215
cm–1) in all the complexes and bidentate
bridging hydrazine (νN–N=985–950 cm–1)
in the metal hydrazine complexes. Both metal carboxylate and metal hydrazine
carboxylate complexes undergo endothermic dehydration and/or dehydrazination
followed by exothermic decomposition of organic moiety to give the respective
metal oxides as the end products except manganese pyrazoledicarboxylate hydrate,
which leaves manganese carbonate. X-ray powder diffraction patterns reveal
that the metal carboxylate hydrates are isomorphous as are those of metal
hydrazine complexes of cobalt, zinc and cadmium. 相似文献
2.
Ulrich Englich Ingo Prass Karin Ruhlandt-Senge Thorsten Schollmeier Frank Uhlig 《Monatshefte für Chemie / Chemical Monthly》2002,133(7):931-943
Summary. Hydrido substituted stannasilanes of the type or (Z = H, Me, Ph; R, R′ = alkyl, Ph) are accessible by reaction of either alkali metal stannides (MSn(Z)R
2; M = Li, Na) with halogen substituted silanes (; X = F, Cl) or chlorostannanes (R
2SnCl2, Ph3SnCl) and fluorosilanes in the presence of magnesium. Stannasilanes with halogen substituents at the silicon as well as the tin atom are formed by
treatment of the hydrido substituted stannasilanes with CHCl3 or CCl4. The hydrido substituted stannasilanes decompose in contact with air to distannanes and siloxanes or to the linear (
t
Bu2Sn(–O–
t
Bu2Si–OH)2) and cyclic ((–
t
Bu2Sn–O–
i
Pr2Si–O–)2) stannasiloxanes.
Received November 29, 2001. Accepted (revised) January 16, 2002 相似文献
3.
L. A. Leites A. V. Zabula S. S. Bukalov P. S. Koroteev O. S. Maslennikova M. P. Egorov O. M. Nefedov 《Russian Chemical Bulletin》2005,54(5):1117-1120
The vibrational spectra of tetravalent metal halides (M = Si, Ge, Sn) and the corresponding dihalocarbene analogs MIIHal2, obtained by the authors, and the relevant published data are compared. The spectra of the MIIHal2 species exhibit inversion of the M-Hal stretching frequencies (νs(MIIHal) > ν as(MIIHal)). This can be used for analytical purposes and allows one to distinguish between the spectra of the MIV and MII halides. The IR and Raman spectra of the complexes of dihalogermylenes and -stannylenes with triphenylphosphine and 1,4-dioxane
also exhibit inversion of the ν(MHal) stretching frequencies. This confirms the conclusion drawn earlier based on the analysis
of the geometric parameters and reactivities of the complexes in question that the divalent state of the M atom in these species
is retained.
Dedicated to Academician N. K. Kochetkov on the occasion of his 90th birthday.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1089–1092, May, 2005. 相似文献
4.
Four new complexes have been synthesized based on the 2,4,5-trifluoro-3-methoxybenzoic acid and 4,4′-bipy of the type [R3Sn(OOCC6HF3OCH3)]2·(4,4′-bpy). All complexes were characterized by elemental, IR, 1H, 13C and 119Sn NMR spectra analyses. Complexes 1 and 4 were also characterized by X-ray crystallography. Crystal structures of 1 and 4 show that the coordination number of tin atom is five and the 2D network is connected by intermolecular C–H···O interactions. 相似文献
5.
Rima Tarozaitė Loreta Tamašauskaitė Tamašiūnaitė Vitalija Jasulaitienė 《Journal of Solid State Electrochemistry》2009,13(5):721-731
Platinum–tin complexes were prepared by the reduction of Pt(IV) with Sn(II) in HCl media and studied by light absorption spectrometry,
X-ray photoelectron spectroscopy (XPS), and electron microscopy. The formation of three complexes, H3[Pt(SnCl3)5], H2[Pt(SnCl3)2Cl2], and H2[Pt3(SnCl3)8], depending on HCl and SnCl2 concentrations, has been shown. The glassy carbon (GC) electrode modified in the complexes solutions was found to be an electrocatalyst
for borohydride oxidation in a 1.0-M NaOH solution. Comparison of BH4
− electrooxidation on Pt and on GC modified with platinum–tin complexes has shown that catalytic hydrolysis of BH4
− did not proceed in the latter case in contrast to its oxidation on the Pt electrode, and only direct BH4
− oxidation has been observed in the positive potentials scan. The activity of Pt–Sn complexes for BH4
− oxidation changes with time and eventually decreases due to Sn(II), bound in the complex with Pt(II), oxidation by atmospheric
oxygen. The complexes may be renewed by addition of missing amounts of SnCl2 and HCl. 相似文献
6.
K. Ramalingam R. Thiruneelakandan G. Bocelli L. Righi 《Transition Metal Chemistry》2012,37(3):265-270
The complexes trans-[Ni(4-MP)2(NCS)2]·MeCN (1) and trans-[Ni(3-MP)2(NCS)2] (2) (4-MP = tri(4-methylphenyl)phosphine, 3-MP = tri(3-methylphenyl)phosphine) were prepared and characterized by IR, UV–visible,
NMR spectra, CV, TGA and single crystal X-ray crystallography. Both the complexes have planar geometry and are diamagnetic.
The Ni–P distances in both complexes are relatively short as a result of strong back donation from nickel to phosphorus. The
phenyl rings in the 3-MP analogue (2) show increased pitching with reference to the plane formed by the ipso carbons due to increased steric effects. For complex
(2), the N–Ni–N and P–Ni–P angles are significantly lower than the almost linear N–Ni–N and N–Ni–P angles observed for both
complex (1) and trans-[Ni(PPh3)2(NCS)2]. This observation indicates that the 3-methylphosphine ligand forces complex (2) to distort towards a tetrahedral geometry. IR spectra of both complexes show strong bands around 2,090 cm−1 due to N-coordinated thiocyanate, while the electronic spectra contain d–d transitions around 452 nm. Cyclic voltammograms
show that the irreversible one-electron reduction potentials increase in the following order: trans- [Ni(PPh3)2(NCS)2] < trans- [Ni(3-MP)2(NCS)2] < trans-[Ni(4-MP)2(NCS)2], revealing the electron releasing effect of the methyl groups. The planar complexes exhibit interallogony in coordinating
solvents. 相似文献
7.
M. Assunta Girasolo Clelia Di Salvo Arturo Silvestri 《Journal of organometallic chemistry》2006,691(4):693-701
The heterocyclic ligands [1,2,4]triazolo-[1,5-a]pyrimidine (tp) and 5,7-dimethyl-[1,2,4]triazolo-[1,5-a]pyrimidine (dmtp), react with diorganotin dichlorides giving the addition compounds Me2SnCl2(tp)2, Et2SnCl2(tp)2, Me2SnCl2(dmtp)2, Et2SnCl2(dmtp)2, Bu2SnCl2(dmtp), Ph2SnCl2(dmtp). The organotin:ligand stoichiometry goes from 1:2 to 1:1 by increasing the steric hindrance of the organic groups bound to tin. The compounds have been characterized by means of infrared, 119Sn Mössbauer and 1H AND 13C NMR spectroscopy.The ligands presumably coordinate to tin classically through the nitrogen atom at the position 3. The 1:1 complexes adopt trigonal bipyramidal structures, with the organic groups on the equatorial plane and the ligand in the apical position. All-trans octahedral structures are inferred for the 1:2 complexes, except for Et2SnCl2(tp)2, characterized by a skew-trapezoidal structure.119Sn Mössbauer measurements, at room temperature, in concomitance with DFT calculations, performed on isomeric structures of R2SnCl2(tp)2 (R = Me, Et), allowed us to conclude that the all-trans octahedral coordination induces self-assembly in the solid state, possibly accomplished through π-π stacking interactions among the planar ligands coordinated to the organotin(IV) compound, while the skew-trapezoidal structure attributed to Et2SnCl2(tp)2, induces the formation of monomeric adducts in the solid state.In vitro antimicrobial tests showed that [n-Bu2SnCl2(dmtp)] has interesting properties as anti Gram-positive and antibiofilm agent. 相似文献
8.
Mirjana Mladenović Peter Botschwina Peter Sebald Stuart Carter 《Theoretical chemistry accounts》1998,100(1-4):134-146
The results of various ab initio calculations are reported for the electronic ground state of the acetylide anion. An “Eyring's
lake” in the T-shaped configuration is identified with six different methods (SCF, MP2, CCSD, CCSD-T, CCSD(T), and CEPA–1).
The equilibrium bond lengths of HCC− are estimated to be r
e
(CH)=1.0689(3) ? and R
e
(CC)=1.2464(2) ?, and the ground-state rotational constant is predicted to be B
0=41636(20)MHz. The large permanent dipole moment of μ0=−3.093D should facilitate detection of the anion by microwave spectroscopy. The band centers are predicted to be 3211.3cm−1(ν1), 511.1cm−1(ν2), and 1805.0cm−1(ν3). A large transition dipole moment of 0.477 D is calculated for the ν2 band. Rovibrational levels of HCC− up to approximately 20 000 cm−1 above equilibrium are calculated with DVR-DGB and FBR methods on the basis of a previous CEPA–1 potential energy surface.
Different energy patterns are found and discussed, for which anharmonic and Coriolis resonances are shown to play an important
role.
Received: 27 July 1998 Accepted: 12 August 1998 / Published online: 19 October 1998 相似文献
9.
R. R. Aysin P. S. Koroteev A. A. Korlyukov A. V. Zabula S. S. Bukalov L. A. Leites M. P. Egorov O. M. Nefedov 《Russian Chemical Bulletin》2010,59(2):348-360
The Raman and IR spectra of the complexes (CO)5CrSnCl2·THF (1), (CO)5WSnCl2·THF (2), (CO)5CrGeCl2·THF (3), (CO)5WGeCl2·THF (4), (CO)5CrSnCl2·2THF (5), and (CO)5WSnCl2·2THF (6) were measured and interpreted using quantum chemical calculations. Complexes 3 and 5 were characterized by X-ray analysis. The stretching vibrations of the CO groups in the spectra of solutions of complexes
1–6 obey the selection rules for C
4ν
local symmetry. For the complexes containing 0 (type A), 1 (type B), and 2 (type C) THF molecules, a comparison was made
of the calculated and experimental M$
\underline \cdots
$
\underline \cdots
EII bond lengths and energies, as well as the ν(CO) vibrational frequencies. The contribution of the π-component to the M$
\underline \cdots
$
\underline \cdots
EII bond decreases in the order A→B→C and leads to enhancement of the donor ability of the carbene-like ligand and to a slight
elongation and weakening of this bond. An attempt to grow crystals of complex 6 in air unexpectedly resulted in a polynuclear complex [(CO)5WSn(Cl)(μ-OH)2SnCl2(μ-OH)]2·6THF, which was characterized by X-ray analysis and Raman spectroscopy. 相似文献
10.
11.
M. Rafiq S. Ali S. Shahzadi M. Shahid S. K. Sharma K. Qanungo 《Journal of the Iranian Chemical Society》2014,11(1):169-178
Organotin complexes have been synthesized by refluxing 2-mercapto-5-methyl benzimidazole with R2SnCl2/R3SnCl (R = Me, n-Bu, Ph) in 1:1 molar ratio in the first step. In the second step, synthesized organotin(IV) complexes were treated with CS2 and R2SnCl2/R3SnCl/PdCl2 to yield homo- and heterobimetallic complexes. The composition of the synthesized complexes, the bonding behavior of the donor groups, and structural assignments were studied by elemental analysis and different spectral techniques, including IR and multinuclear NMR (1H, 13C). The IR data shows bidentate nature of the ligand which is also confirmed by semiempirical study, while NMR data confirms the four-coordinated geometry in solution. The free ligand and its respective homo- and heterobimetallic complexes were screened in vitro against a number of microorganisms to assess their biocidal properties. The biological activity data show that complexes exhibits significant antibacterial and antifungal activities as compared to ligand with few exceptions. 相似文献
12.
Erik Rakovsky ?udmila ?úrková Jaromír Marek 《Monatshefte für Chemie / Chemical Monthly》2002,22(2):277-283
Anhydrous 1,6-hexanediammonium dihydrogendecavanadate ((HdaH2)2H2V10O28, 1) was prepared by reaction of V2O5 with 1,6-hexanediamine in aqueous solution. The crystal structure of 1 was determined, and the proton positions in the H2V10O28 4− anion were calculated by the bond length/bond number method. The protons are bound to the centrosymmetrically oriented μ–OV3 groups of the decavanadate anion. Based on the analysis of IR spectra of 1 prepared from H2O and D2O, the absorption band at 871 cm−1 can be attributed to δ(V–Ob–H) vibrations. 相似文献
13.
N. Tabassam S. Ali S. Shahzadi M. Shahid M. Abbas Q. M. Khan S. K. Sharma K. Qanungo 《Russian Journal of General Chemistry》2013,83(12):2423-2437
Seven different organotin(IV) complexes have been synthesized by reacting 2-ethylanilinocarbonylpropenoic acid with R2SnCl2/R3SnCl under reflux conditions. The organotin(IV) complexes along with ligand have been characterized by different techniques including elemental analysis, FT-IR and multinuclear NMR (1H and 13C). IR data show that complexation occurs through -COO site and the ligand is bidentate which is also confirmed by the semi-empirical quantum-mechanical study. 1H and 13C NMR data confirm the tetrahedral geometry of complexes in solution. The complexes as well as the ligand were also checked for various 相似文献
14.
I. I. Seifullina N. V. Shmatkova R. I. Zubatyuk O. V. Shishkin A. V. Mazepa 《Russian Journal of Inorganic Chemistry》2013,58(1):26-32
The reactions of SnCl4 with picolinoylhydrazones of 2-hydroxybenz-(2-hydroxynaphth)aldehydes (H2Ps, H2Pnf) in CH3OH gave non-electrolyte complexes [SnCl3(Ps · H)] · CH3OH (I) and [SnCl3(Pnf · H)] · CH3OH (II). The imide form of the ligand coordinated to Sn(IV) through the azomethine nitrogen atom and oxyazine and oxy oxygen atoms was proved by UV/Vis, IR, and 1H NMR spectroscopy. The negative charge on the coordination unit thus arising is counterbalanced by the positive charge caused by the protonation of ligands at the pyridine nitrogen atom of the heterocycle. It was shown that dehydrochlorination of the complexes affords tin-containing species, which correlates with the presence of the corresponding peaks [SnCl2(Ps)]+ and [SnCl2(Pnf)]+ in their mass spectra. The molecular and crystal structures of complexes I and II were determined by X-ray diffraction. 相似文献
15.
New unsymmetrical Schiff base ligand (H2L) is prepared via condensation of 2-hydroxy-5-methyl acetophenone, 2-hydroxy-5-chloro-3-nitro acetophenone and carbohydrazide
in 1:1:1 ratio. Metal complexes of VO(IV), Cr(III), Mn(III), Fe(III), Zr(IV), MoO2(VI), WO2(VI) and UO2(VI) have been prepared. These complexes were characterized by elemental analysis, UV–Vis and IR spectroscopy and magnetic
moment and thermogravimetric analysis. The purity of the ligand and the metal complexes is confirmed by microanalyses, while
unsymmetrical nature of ligand was further corroborated by 1H NMR. All the complexes are air stable and insoluble in water and common organic solvents but fairly soluble in DMSO. The
elemental analysis shows 1:1 metal to ligand stoichiometry for all the complexes. Thermal behaviour of the complexes was studied,
the complexes were found to be quite stable and their thermal decomposition was generally via partially loss of the organic
moiety and ended with respective metal oxide as a final product. Comparison of the IR spectrum of ligand and its metal complexes
confirm that Schiff base behave as a dibasic tetradentate ligand towards the central metal ion with an ONNO donor sequence.
The dc electrical conductivity is studied and data obtained obeyed the relation σ = σ
0 exp(−E
a/kT) over the temperature range 40–130 °C. X-ray diffraction study of VO(IV) complex shows its crystalline nature with triclinic
crystal system. 相似文献
16.
Two heteronuclear complexes Mo2Ag4(μ-dppm)4(mnt)6 · 6MeCN (1) and WAg2(μ-dppm)2(mnt)3 · MeCN (2) were synthesized by self-assembly with [Ag2(μ-dppm)2(MeCN)2](SbF6)2 and [Bu4N]2[Mmnt)3] (M=Mo or W, dppm=bis(diphenylphosphino)methane, mnt2− = cis-1,2-dicyanoethylene-1,2-dithiolate) as components and characterized by IR spectra, elemental analysis, 1H NMR spectra, 31P NMR spectra and u.v.–vis spectra. The crystal structures of the two complexes were determined by X-ray analysis. 相似文献
17.
Erik Rakovský Ľudmila Žúrková Jaromír Marek 《Monatshefte für Chemie / Chemical Monthly》2002,133(3):277-283
Summary. Anhydrous 1,6-hexanediammonium dihydrogendecavanadate ((HdaH2)2H2V10O28, 1) was prepared by reaction of V2O5 with 1,6-hexanediamine in aqueous solution. The crystal structure of 1 was determined, and the proton positions in the H2V10O28
4− anion were calculated by the bond length/bond number method. The protons are bound to the centrosymmetrically oriented μ–OV3 groups of the decavanadate anion. Based on the analysis of IR spectra of 1 prepared from H2O and D2O, the absorption band at 871 cm−1 can be attributed to δ(V–Ob–H) vibrations.
Received August 3, 2001. Accepted (revised) October 8, 2001 相似文献
18.
The reaction of zinc bromide with the pentadentate chelating ligand 2, 6‐diacetylpyridine bis(thiosemicarbazone) (H2L1) yields the formation of a novel complex. Recrystallization in a acetone/water solution leads us to isolate the mixed ligand complex of [Zn(H2L1)Br0.49(OH)0.51]2·(HSO4)2·6H2O, structurally characterized. The complex is a dimer in which each zinc atom is seven‐co‐ordinated with the SNNNS‐chelating ligand occupying the five equatorial positions, a bromine atom or hydroxo group in one of the two axial positions and a sulfur atom of the centrosymmetrical molecule occupies the other axial site making a bridge between the two zinc atoms. To the best of our knowledge is the first S‐bridged dimeric Zinc(II) complex derived from 2, 6‐diacetylpyridine bis(thiosemicarbazone) ligand. The MALDI‐TOF mass, solid state IR and 1H NMR (in DMSO solution) spectra are also discussed. 相似文献
19.
Four nickel carbonate-bearing minerals from Australia have been investigated to study the effect of Ni for Mg substitution.
The spectra of nullaginite, zaratite, widgiemoolthalite and takovite show three main features in the range of 26,720–25,855 cm−1 (ν1-band), 15,230–14,740 cm−1 (ν2-band) and 9,200–9,145 cm−1 (ν3-band) which are characteristic of divalent nickel in six-fold coordination. The Crystal Field Stabilization Energy (CFSE)
of Ni2+ in the four carbonates is calculated from the observed 3A2g(3F) → 3T2g(3F) transition. CFSE is dependent on mineralogy, crystallinity and chemical composition (Al/Mg-content). The splitting of the
ν1- and ν3-bands and non-Gaussian shape of ν3-band in the minerals are the effects of Ni-site distortion from regular octahedral. The effect of structural cation substitutions
(Mg2+, Ni2+, Fe2+ and trivalent cations, Al3+, Fe3+) in the carbonate minerals is noticed on band shifts. Thus, electronic bands in the UV–Vis–NIR spectra and the overtones
and combination bands of OH and carbonate ion in NIR show shifts to higher wavenumbers, particularly for widgiemoolthalite
and takovite. 相似文献
20.
Sevagapandian Sankarapandian Rajagopal Gurusamy Nehru Kasi Athappan Periakaruppan 《Transition Metal Chemistry》2000,25(4):388-393
Complexes of the general formula, ML2 [M = CuII, NiII, CoII and OVIV; L = 1,2,3,5,6,7,8,8a-octahydro-3-hydroxyimino-N-(4-X-phenyl)-l-phenyl-5-(phenylmethylene)-2-naphthalenecarboxamide (X =
H, Me, OMe, Cl)] have been prepared and characterized on the basis of elemental analysis, magnetic moments and i.r., e.p.r.
and electronic spectra. These metal complexes contain the N4 chromophore with the ligand coordinating through nitrogens of the azomethine and deprotonated anilide functions. C.v. measurements
indicate that the copper(II) complexes are quasi-reversible in acetonitrile solution. Square planar and square pyramidal structures
are assigned respectively to the copper(II) and oxovanadium(IV) complexes, whereas tetrahedral geometry is assigned to the
nickel(II) and cobalt(II) complexes. Deprotonated anilide nitrogen is involved in coordination and the presence of an electron-donating
group para to the anilide function decreases the ΔE values of the d–d transitions while the value is found to increase when electron-withdrawing groups are substituted. Line
spacing in the e.p.r. spectra of the copper(II) and oxovanadium(IV) complexes increases when methyl group is para to the anilide group, and decreases when this group is replaced by methoxy or chloro. The ν(C–N) of the anilide group and
the ν(C-N) of the azomethine function of the oxime metal complexes are metal-sensitive and the blue shift for the above stretching
frequencies follows the order: copper(II) > oxovanadium(IV) > nickel(II) ≈ cobalt(II).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献