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1.
The reaction of Ru3(CO)10(dotpm) ( 1 ) [dotpm = (bis(di‐ortho‐tolylphosphanyl)methane)] and one equivalent of L [L = PPh3, P(C6H4Cl‐p)3 and PPh2(C6H4Br‐p)] in refluxing n‐hexane afforded a series of derivatives [Ru3(CO)9(dotpm)L] ( 2 – 4 ), respectively, in ca. 67–70 % yield. Complexes 2 – 4 were characterized by elemental analysis (CHN), IR, 1H NMR, 13C{1H} NMR and 31P{1H} NMR spectroscopy. The molecular structures of 2 , 3 , and 4 were established by single‐crystal X‐ray diffraction. The bidentate dotpm and monodentate phosphine ligands occupy equatorial positions with respect to the Ru triangle. The effect of substitution resulted in significant differences in the Ru–Ru and Ru–P bond lengths.  相似文献   

2.
X‐ray photoelectron spectral study was made on the complexes Ni(nmedtc)2( 1 ), [Ni(nmedtc)(PPh3)2]ClO4( 2 ), [Ni‐(nmedtc)(dppe)]BPh4( 3 ) (where nmedtc = N‐methyl, N‐ethanoldithiocarbamate, dppe = 1, 2‐bis(diphenylphosphino)ethane). The nickel 2p3/2 binding energy values for chelated and free phosphine complexes are 854.0 and 854.1 eV which are significantly different from Ni2p3/2 BE value of NiS4 chromophore, indicating the relative dearth of electron density on Ni in NiS2P2 chromophores. The presence of two phosphine groups in NiS2P2 chromophore alleviates the electron density on the metal atom. More electron density is being pulled away from the metal atom in chelates than in the PPh3 analogue. This observation is in line with solution studies by cyclic voltammetry. A one‐electron reduction potential was observed to be the minimum for NiS2P2 chromophores compared to the others. Also the crystal structure of the complex [Ni(pipdtc)(1, 4‐dppb)]ClO4 (pipdtc = piperidinecarbodithioato anion, 1, 4‐dppb = bis(diphenylphosphino)butane) prepared by the reaction between Ni(pipdtc)2, NiCl2�622O, and 1, 4‐dppb in CH3CN‐CH3OH is reported.  相似文献   

3.
Three new transition metal complexes [Zn(bipyrtds)I2]( 1 ), [Cd(bipyrtds)I2] ( 2 ) and [Hg(pipdtc)I]( 3 ) (where bipyrtds = bipyrrolidine thiuamdisulfide and pipdtc = piperidinecarbodithioate) were prepared by the reaction of the corresponding biscarbodithioates with iodine and were characterized by elemental analysis, IR and NMR spectra. The structures of all the three complexes were determined by single crystal X‐ray crystallography. Compounds 1 and 2 contain four coordinated metal atoms and both ZnII and CdII complexes are isostrucutral. Interestingly, complex 3 was found to contain effectively four coordinated mercury atom as a dimer with a relatively long Hg‐S (3.084Å) bond. The IR studies are in keeping with the observed thioureide distances. 1H NMR spectra of 1 and 2 show clear differences in environments of α‐ and β‐CH2 protons. However, in 1 a broad signal was observed at 4.02 ppm for α‐protons and a multiplet at 2.10 for β‐protons. For 2 , two triplets appeared at 4.26 and 4.03 ppm for α‐protons and two quintets appeared in the range of 2.18 and 2.28 ppm for β‐protons. Complex 3 gave three sets of signals. Variation of stereochemical environment with respect to α and β protons of the rings is very clearly observed in the NMR spectra.  相似文献   

4.
[Tetrakis(acetonitrile)‐dibromo‐nickel(II)]‐di‐acetonitrile was obtained from a solution of nickel(II) dibromide in acetonitrile at 258 K. The crystal structure [monoclinic, P21/n (no.14), a = 1005.5(5), b = 831.3(5) , c = 1131.7(5) pm, β = 106.263(5)°, V = 908.1(8)·106 pm3, Z = 2, R1 for 1580 reflections with I0>2σ(I0): 0.0505] contains sixfold coordinated NiII atoms. Two trans coordinating bromide anions and four equatorial acetonitrile molecules form an elongated octahedron around the central NiII atom. [Ni(CH3CN)4Br2] octahedra are connected via hydrogen bonds to neighboring octahedra as well as to solvate acetonitrile molecules.  相似文献   

5.
Crystalline samples of La3Ni2B2N3 were synthesized using solid state metathesis reactions from combinations of La, LaCl3, NiCl2 together with Li3BN2. The structure was determined by single crystal X‐ray diffraction (I4/mmm (No. 139), a = 372.95(2) pm, c = 2056.3(2) pm, R1 = 0.027, wR2 = 0.062) and confirmed earlier results from neutron powder diffraction. La3Ni2B2N3 contains BN units capping square planar Ni layers. Isolated nitrogen atoms reside in La6 octahedra. Magnetic measurements on several bulk samples exhibit superconductivity at temperatures below 14.6 K.  相似文献   

6.
A novel ligand, N,N′‐Bis‐[3‐(2‐nitrophenyl)‐allylidene]‐ethane‐1,2‐diamine (nca2en), and their corresponding copper(I) complexes, [Cu(ncaen)2]ClO4 ( 1 ), and [Cu(nca2en)(PPh3)2]BPh4 ( 2 ), have been synthesized and characterized by CHN analyses, 1H and 13C‐NMR, IR, and UV‐Vis spectroscopy. The crystal and molecular structures of [Cu(ncaen)2]ClO4 ( 1 ), and [Cu(nca2en)(PPh3)2]BPh4 ( 2 ), were determined by X‐ray crystallography from single‐crystal data. The coordination polyhedron about the copper(I) atom in the two complexes is best described as a distorted tetrahedron. A quasireversible redox behavior is observed for complex 1 and 2 (E1/2 = 0.55 and 0.95 V, respectively).  相似文献   

7.
The synthesis of the new perfluorinated 4‐(4′‐trifluoromethyl‐tetrafluorophenoxy)‐tetrafluoroaniline (RFNH2, 4 ) was accomplished via a 4‐step route involving standard procedures: carboxylation of RFLi, chlorination of RFCOOH ( 1 ), amidation of RFCOCl ( 2 ) and Hofmann degradation of RFCONH2 ( 3 ). Diazotation and reaction with azide as well as treatment of 4 with acid chlorides produced the pseudohalides RFN3 ( 5 ), RFNCS ( 6 ) and RFNCO ( 7 ). The reaction with oxalyl chloride led to the formation of two products RFNHCOCOCl ( 8 ) and RFNHCOCONHRF ( 9 ). The thionyl imide RFNSO ( 10 ) is formed upon reaction with thionyl chloride. All products were identified and characterized by spectroscopic methods. The molecular structures of 1 , 2 , 5 , 6 , 9 and RFCN ( 3 a ) have been determined by X‐ray crystallography, among them the azide 5 and the isothiocyanate 6 as the first crystal structures of perfluorinated azides/isothiocyanates bound to carbon.  相似文献   

8.
The structure of ammonium hexafluoroarsenate, NH4AsF6, has been determined by X‐ray diffraction using a single crystal grown from saturated solution in anhydrous HF. NH4AsF6 crystallizes rhombohedral with the KOsF6 structure type, with a = 7.459(3) Å, c = 7.543(3) Å (at 200 K), Z = 3, space group (No. 148). No phase transition was observed in the 100 K–296 K temperature range. The structure is dominated by regular AsF6 octahedra and disordered NH4+ cations. Raman spectrum of a single crystal of NH4AsF6 shows the bands at 372 cm?1, 572 cm?1, 687 cm?1 (AsF6?) and at 3240 cm?1 and 3360 cm?1 (NH4+).  相似文献   

9.
The η1‐thiocarbamoyl palladium complexes [Pd(PPh3)(η1‐SCNMe2)(η2‐S2R)] (R = P(OEt)2, 2 ; CNEt2, 3 ) and trans‐[Pd(PPh3)21‐SCNMe2)(η1‐Spy)], 4 , (pyS: pyridine‐2‐thionate) are prepared by reacting the η2‐thiocarbamoyl palladium complex [Pd(PPh3)22‐SCNMe2)][PF6], 1 with (EtO)2PS2NH4, Et2NCS2Na, and pySK in methanol at room temperature, respectively. Treatment of 1 with dppm (dppm: bis(diphenylphosphino)methane) in dichloromethane at room temperature gives complex [Pd(PPh3)(η1‐SCNMe2)(η2‐dppm)] [PF6], 5 . All of the complexes are identified by spectroscopic methods and complex 1 is determined by single‐crystal X‐ray diffraction.  相似文献   

10.
Pale‐green crystals of the title complex were prepared by reaction of 2‐formylpyridine semicarbazone (HCSpy) and nickel(II) perchlorate in boiling ethanol. The crystals are triclinic with the nickel ion in an octahedral arrangement, coordinated by two nitrogen atoms and one oxygen donor atom from each ligand molecule. The effect of coordination on bond lengths and angles was explored by comparison with the single‐crystal structure data of the free ligand HSCpy, which was collected as well. The assumed coordination mode was supported by 1H and 13C NMR spectroscopic data. A detailed analysis of the electronic properties, including semi‐empirical quantummechanical calculations is presented. Furthermore, the data obtained from magnetic susceptibility and EPR measurements are in accordance with a low‐spin d8 nickel(II) complex.  相似文献   

11.
A homo‐dinuclear NiII complex was prepared from 2, 6‐bis(3, 5‐dimethylpyrazolyl)pyridine (Me4‐bpp) and azide ions in nonaqueous media. It was characterized by single crystal X‐ray structural analysis, IR spectroscopy, and elemental analysis. In addition, the electrochemical properties of the compound were determined with cyclic voltammetry in DMF. The title compound crystallizes in the P21/n monoclinic space group, with unit cell parameters a = 8.978(1), b = 12.459(1), c = 17.764(1) Å, ß =100.603(3)°, V = 1953.0(3) Å3, Z = 2. The Ni2+ ion has a distorted octahedral environment involving three nitrogen atoms of the Me4‐bpp ligand, two nitrogen atoms from the bridged azide group, and one nitrogen atom from the terminal azide group. The Ni···Ni distance is 3.273(5) Å.  相似文献   

12.
Synthesis, spectral and cyclic voltammetric characterization of [Ni(dedtc)(4‐MP)2](ClO4) ( 1 ), [Ni(dedtc)(4‐MP)(NCS)]( 2 ), [Ni(dedtc)(PPh3)(NCS)] ( 3 ) and [Ni(dedtc)(PPh3)(CN)] ( 4 ) (dedtc = diethyldithiocarbamate, 4‐MP = tri(4‐methylphenyl)phosphine, PPh3 = triphenylphophine) are reported. IR spectra of complexes 1‐4 show the characteristic thioureide (C‐N) bands at higher wave numbers compared to that of the parent dithiocarbamate complex [Ni(dedtc)2]. The d‐d transitions are observed in the region 452—482 nm. The CV studies clearly show the presence of reduced electron density on the nickel ions in mixed ligand complexes 1‐4 compared to the parent dithiocarbamate. Single crystal X‐ray structure studies show all the complexes to containplanar NiS2P2, NiS2PN, and NiS2PC chromophores in keeping with the observed diamagnetism. In all the complexes the Ni‐S distances are asymmetric. The thioureide C‐N distance of the complexes 1‐4 are less thanthe C‐N distance observed in the parent [Ni(dedtc)2].  相似文献   

13.
The crystal structure of the mixed oxide InGaO3(ZnO)4 has been determined from electron diffraction and single‐crystal X‐ray diffraction data. The compound crystallises in a hexagonal space group (P63/mmc; No. 194), deduced from convergent beam electron diffraction (CBED). Single crystals of InGaO3(ZnO)4 were grown from a K2MoO4 flux in sealed platinum tubes. Single crystal structure refinement from XRD data [a = 3.2850(2) Å; c = 32.906(3) Å; Z = 2; 4232 data, R1 = 0.0685] reveals a compound with oxygen anions forming a closest‐packed arrangement. Within this packing In3+ cations occupy octahedral interstices, forming layers of edge sharing octahedra. In between these layers are regions with composition [Zn4GaO5]+ forming a wurtzite type of structure. Inversions of the ZnO4 tetrahedra occurs (i) at the InO6 octahedral layer and (ii) halfway in the wurtzite type region, where the inversion boundary is built by Ga3+ in trigonal bipyramidal coordination with a long Ga–Oapical distance of 2.19(1) Å. The site occupation of Zn2+ and Ga3+, respectively, was confirmed by bond valence sum calculations. The compounds described here have the same structural charactistics as other known members with general formula ARO3(ZnO)m with m = integer.  相似文献   

14.
[Et2Sn(O2AsMe2)2] ( 1 ) and [Ph2Sn(O2AsMe2)(μ‐OMe)]2 ( 2 ) were synthesized by treatment of Et2SnO and Ph2SnS with HO2AsMe2 in Methanol, respectively. The compounds were characterized by elemental analyses, vibrational spectroscopy and mass spectrometry. According to X‐ray diffraction measurements compound 1 crystallizes monoclinic in space group P21/n with cell parameters a = 804.89(3), b = 987.11(5), c = 966.42(4) pm, β = 113.354(3)°. The unit cell parameters of 2 , which crystallizes in the same space group, are a = 974.4(1), b = 1463.3(1), c = 1228.9(1) pm, β = 111.324(3)°. The (SnOAsO)4 rings of 1 are linked and form a two‐dimensional network with the SnEt groups pointing into the holes of the next layer. Compound 2 occurs as a dimer with internal Sn(OMe)2Sn bridges in the (SnOAsO)2 rings. The vibrational and mass spectra are given and discussed.  相似文献   

15.
Hydrothermally synthesized CsHSi2O5 was studied by single‐crystal X‐ray diffraction. The compound is orthorhombic (space group Pnma). Unit cell parameters are a = 4.9758(3), b = 8.8089(6), c = 12.9295(9) Å with four formula units per cell. The structure was solved by direct methods and refined to a residual R1 = 0.025 for 621 independent observed reflections with I > 2σ(I) and 41 parameters. Residual electron densities were used to locate positions of the H atoms. They are part of silanol groups and show a disorder involving two positions related by a center of symmetry. The resulting O—H···O distance of 2.44 Å is one of the shortest hydrogen bonded O···O distances in inorganic compounds containing silanol groups. The structure belongs to the class of unbranched zweier double chain silicates. The [Si2O4(OH)] chains run parallel [100]. Cesium cations providing additional linkage between the anionic ribbons reside in voids between the chains and coordinate to nine oxygen ligands.  相似文献   

16.
The reaction of different stoichiometric amounts of Zn(NCS)2 with 3‐cyanopyridine in different solvents leads to the formation of several new coordination compounds, which were structurally characterized and investigated for their thermal behavior. In Zn(NCS)2(3‐cyanopyridine)4 ( 1 ) and Zn(NCS)2(3‐cyanopyridine)2(H2O)2 · (3‐cyanopyridine)2 ( 2 ) the zinc cations are octahedrally coordinated by two terminally N‐bonded thiocyanate anions and four 3‐cyanopyridine ( 1 ) or two 3‐cyanopyridine and two water molecules ( 2 ) within slightly distorted octahedra. Zn(NCS)2(3‐cyanopyridine)2 ( 3 ) and Zn(NCS)2(3‐cyanopyridine)2 · (H2O)0.5 ( 3‐H2O ) also form discrete complexes but with tetrahedrally coordinated Zn cations. Upon heating compound 1 decomposes without the formation of any intermediate compound. In contrast, compound 2 loses the water molecules in the first step and transforms into compound 1 . Surprisingly, upon further heating a second TG step is observed, in which compound 3 is formed as an intermediate, which is not observed if compound 1 is heated directly. The tetrahedral complex 3 melts leading to the formation of an amorphous phase. If the hemihydrate 3‐H2O is heated, it transforms into 3 via melting and crystallization but there are hints that a metastable phase might form as intermediate on water removal.  相似文献   

17.
Ni(NH3)Cl2 and Ni(NH3)Br2 were prepared by the reaction of Ni(NH3)2X2 with NiX2 at 350 °C in a steel autoclave. The crystal structures were determined by X‐ray powder diffraction using synchrotron radiation and refined by Rietveld methods. Ni(NH3)Cl2 and Ni(NH3)Br2 are isotypic and crystallize in the space group I2/m with Z = 8 and for Ni(NH3)Cl2: a = 14.8976(3) Å, b = 3.56251(6) Å, c = 13.9229(3) Å, β = 106.301(1)°; Ni(NH3)Br2a = 15.5764(1) Å, b = 3.74346(3) Å, c = 14.4224(1) Å, β = 105.894(1)°. The crystal structures are built up by two crystallographically distinct but chemically mostly equivalent polymeric octahedra double chains [NiX3/3X2/2(NH3)] (X = Cl, Br) running along the short b‐axis. The octahedra NiX5NH3 share common edges therein. The crystal structures of the ammines Ni(NH3)mX2 with m = 1, 2, 6 can be derived from that of the halides NiX2 (X = Cl, Br) by successive fragmentation of its CdCl2 like layers by NH3.  相似文献   

18.
Reactions of pyrimidine‐2‐thione (HpymS) with PdII/PtIV salts in the presence of triphenyl phosphine and bis(diphenylphosphino)alkanes, Ph2P‐(CH2)m‐PPh2 (m = 1, 2) have yielded two types of complexes, viz. a) [M(η2‐N, S‐ pymS)(η1‐S‐ pymS)(PPh3)] (M = Pd, 1 ; Pt, 2 ), and (b) [M(η1‐S‐pymS)2(L‐L)] {L‐L, M = dppm (m = 1) Pd, 3 ; Pt, 4 ; dppe (m = 2), Pd, 5 ; Pt, 6 }. Complexes have been characterized by elemental analysis (C, H, N), NMR spectroscopy (1H, 13C, 31P), and single crystal X‐ray crystallography ( 1 , 2 , 4 , and 5 ). Complexes 1 and 2 have terminal η1‐S and chelating η2‐N, S‐modes of pymS, while other Pd/Pt complexes have only terminal η1‐S modes. The solution state 31P NMR spectral data reveal dynamic equilibrium for the complexes 3 , 5 and 6 , whereas the complexes 1 , 2 and 4 are static in solution state.  相似文献   

19.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XX Formation and Structure of [{η2tBu2P–P}Pt(PHtBu2)(PPh3)] [{η2tBu2P1–P2}Pt(P3Ph3)(P4Ph3)] ( 2 ) reacts with tBu2PH exchanging only the P3Ph3 group to give [{η2tBu2P1–P2}Pt(P3HtBu2)(P4Ph3)] ( 1 ). The crystal stucture determination of 1 together with its 31P{1H} NMR data allow for an unequivocal assignment of the coupling constants in related Pt complexes. 1 crystallizes in the triclinic space group P1 (no. 2) with a = 1030.33(15), b = 1244.46(19), c = 1604.1(3) pm, α = 86.565(17)°, β = 80.344(18)°, γ = 74.729(17)°.  相似文献   

20.
Phosphoraneiminato‐ and Phosphaneimine Complexes of Nickel(II). Crystal Structures of [Ni(O3SCF3)(NPMe3)]4, [Ni4Br5{NP(NMe2)3}3], [NiBr2{HNP(NMe2)3}2], and [Ni(PMePh2)4] Black‐violet single crystals of [Ni(O3SCF3)(NPMe3)]4 ( 1 ) have been prepared from [NiBr(NPMe3)]4 and copper(I)triflate by metathesis reaction. The nickel atoms are associated via μ3‐N bridges of the (NPMe3) groups to form a heterocubane. The triflate ions are bonded to the Ni atoms in a chelate fashion. Blue single crystals of [Ni4Br5{NP(NMe2)3}3] ( 2 ) are obtained by the reaction of NiBr2 with Me3SiNP(NMe2)3 in boiling toluene in the presence of sodium fluoride. The Ni atoms in 2 are associated with three μ3‐bridged nitrogen atoms of the (NP(NMe2)3) groups as well as by a μ3‐Br atom to give a distorted heterocubane. Deep blue single crystals of the phosphaneimine complex [NiBr2{HNP(NMe2)3}2] ( 3 ) are formed from Me3SiNP(NMe2)3 and NiBr2 in boiling dichloromethane. In 3 the Ni atom is tetrahedrally coordinated by the bromine atoms and by the nitrogen atoms of the phosphane imine molecules. Pale red crystals of [Ni(PMePh2)4] ( 4 ) have been obtained by the reaction of [NiBr(NPMe3)]4 with lithium phenylacetilyde in the presence of PMePh2. In 4 the Ni atom is distorted tetrahedrally coordinated by the phosphorus atoms of the phosphane molecules with Ni–P distances of 219.9 pm in average. 1 – 4 have been characterized by crystallographic X‐ray analyses. 1 : Space group P21/n, Z = 4, lattice dimensions at 193 K: a = 1566.7(2); b = 1479.9(1); c = 1960.6(2) pm; β = 105.908(9)°; R = 0.0443. 2 · 3 CH2Cl2: Space group P21/c, Z = 4, lattice dimensions at 293 K: a = 1226.0(3); b = 1614.0(3); c = 2406.0(5) pm; β = 92.34(3)°; R = 0.0703. 3 : Space group C2/c, Z = 4, latttice dimensions at 203 K: a = 1840.7(1); b = 810.1(1); c = 1607.2(2) pm; β = 94.74(1)°, R = 0.0340. 4 : Space group P1, Z = 2, lattice dimensions at 223 K: a = 1053.1(2); b = 1315.0(3); c = 1674.5(3) pm; α = 81.55(1)°; β = 79.15(2)°; γ = 84.91(2)°; R = 0.0497.  相似文献   

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