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1.
A NMR study of the reaction mixture of the square planar [Rh((C4H3S)COCHCOR)(CO)(PPh3)] complex and CH3I, where R = CF3, C6H5 or C4H3S, revealed that two types of alkyl and one (R = CF3) or two (R = C6H5 or C4H3S) types of acyl species exist in the system. Two isomers of each species with an unsymmetrical β-diketonato ligand were observed. 1H-1H NOESY NMR unambiguously showed that the PPh3 group is in the apical position in the more stable RhIII-alkyl product. Theoretical computations of the equilibrium geometry of the possible reaction products, consistent with experimental observations, revealed that the first alkyl product results from trans addition to RhI and that the second thermodynamic alkyl product adopts an octahedral geometry with the PPh3 group and the iodide above and below the square planar plane. Theoretical computations also revealed that the thermodynamic acyl product adopts a square-pyramidal geometry with the COCH3 group in the apical position.  相似文献   

2.
Phosphonium zwitterions of a known type were obtained in high yield via a 1:1 reaction of p-benzoquinone or methoxy-p-benzoquinone with the tertiary phosphines R3P [R = (CH2)3OH, Ph, Et, Me] and Ph2MeP, in acetone or benzene at room temperature. In all cases, attack of the P-atom occurs at a C-atom rather than at an O-atom. The products were characterized to various degrees by elemental analysis, 31P{1H}, 1H and 13C NMR spectroscopies, and mass spectrometry, and two of the zwitterions, the new [HO(CH2)3]3P+C6H2(O)(OH)(MeO) and the known Ph3P+C6H3(O)(OH), were structurally characterized by X-ray analysis. The PEt3 reaction also produces small amounts of the ‘dimeric’, μ-oxo co-product Et3P+C6H2(O)(OH)-O-C6H3(O)P+Et3 that is tentatively characterized by 1D- and 2D-NMR data. 2,5-Di-tert-butyl- and 2,3,5,6-tetramethyl-p-benzoquinone do not react with [HO(CH2)3]3P under the conditions noted above. Heating D2O solutions of the water-soluble zwitterions R3P+C6H3(O)(OH) [R = (CH2)3OH, Et] at 90 °C for 72 h leads to complete H/D exchange of the H-atom in the position ortho to the phosphonium center.  相似文献   

3.
Trityl borate salts [4-RPyCPh3][B(C6F5)4] (R = H 1, tBu 2, Et 3, NMe24) and [R3PCPh3][B(C6F5)4] (R = Me 5, nBu 6, Ph[1] 7, p-MeC6H48) are readily prepared via equimolar reaction of the appropriate pyridine or phosphine and trityl borate [CPh3][B(C6F5)4]. The analogous reactions of PiPr3 affords the product [(p-iPr3P-C6H4)Ph2CH][B(C6F5)4] (9) while the corresponding reactions of Cy3P and tBu3P gave the cyclohexadienyl derivatives [(p-R3PC6H5)CPh2][B(C6F5)4] (R = Cy 10, tBu 11). X-ray structures of 5 and 9 are reported.  相似文献   

4.
The new compounds [K(C12H24O6)][Rb(C12H24O6)]2Ge9 · 6NH3, [Rb(C12H24O6)]3Ge9 · 9NH3 and [Cs(C12H24O6)]3Ge9 · 6NH3 were prepared by the extraction of binary and ternary phases of the nominal composition K2Rb2Ge9, Rb4Ge9 and K2Cs2Ge9 with liquid ammonia in the presence of 18-crown-6. The resulting crystals were characterized by low temperature X-ray structure analysis. All of them contain the 21 electron cluster , which is coordinated by alkali metal cations in ion-paired arrangements. The cages were assigned their specific point group symmetry and were compared with hitherto known structures.  相似文献   

5.
New oxovanadium(V) complexes with internally functionalized oximes of the type VO{OPri}3−n{ONC(CH3)(Ar)}n] (where Ar = C4H3O-2, C4H3S-2 and C5H4N-2 and n = 1-3) have been prepared in quantitative yields by the reaction of VO(OPri)3 with the corresponding oximes in various stoichiometric ratios in refluxing anhydrous benzene. The products have been characterized by elemental analyses and spectroscopic (FT IR, 1H, 13C{1H} and 51V NMR) studies. FAB mass spectral analysis of [VO{OPri}{ONC(CH3)C4H3S}2] indicates the monomeric nature of the complex. 51V NMR values for these complexes suggest the formation of tetra-coordinate species in solution. However, the single crystal X-ray diffraction studies of [VO{ONC(CH3)(C4H3O-2)}3] and [VO{ONC(CH3)(C4H3S-2)}3] · 0.5C6H6 exhibit the presence of vanadium(V) atoms in a unique hepta-coordination state with distorted pentagonal bipyramidal geometry in the solid state. The oxo- atom occupies the axial position while the oximato ligands are bonded in a dihapto (η2-N,O) manner with the formation of three membered rings.  相似文献   

6.
A novel chain-like luminescent samarium coordination polymer {Sm3(C8H4O4)4(C12N2H8)2(NO3)}n (C8H4O4 = phthalate, C12N2H8 = 1,10-phenanthroline) has been assembled by hydrothermal process. The title complex crystallizes in the monoclinic system, space group P2(1)/c, with lattice parameters a = 22.56(3) Å, b = 11.155(15) Å, c = 20.32(3) Å, β = 96.70(2)°, V = 5078(12) Å3, F(000) = 2964, GOF = 0.857, R1 = 0.0358, wR2 = 0.0597, Z = 4. Samarium ions exhibit different coordination modes from each other and lead to the unexpected high asymmetrical structure. To our knowledge, it is the first example of lanthanide coordination polymers comprising the three asymmetrical central Sm3+ fragments. The photophysical properties have been studied with excitation and emission spectra.  相似文献   

7.
The new aryl phosphinites PPh2OR (R = 2,4,6-Me3C6H2, 1; R = 2,6-Ph2C6H3, 2) have been prepared from chlorodiphenylphosphine and the corresponding phenols. In these ligands, the ortho-positions of the aromatic phosphite function are blocked by methyl and phenyl substituents, which allows coordination to metal centres without ortho-metallation. Thus, reaction with [PdCl2(cod)] leads to the complexes trans-[PdCl2(PPh2OR)2] (R = 2,4,6-Me3C6H2, 3; R = 2,6-Ph2C6H3, 4), while the reaction with [Rh2(CO)4Cl2] gives trans-[Rh(CO)Cl(PPh2OR)2] (R = 2,4,6-Me3C6H2, 5; R = 2,6-Ph2C6H3, 6). The single-crystal X-ray structure analyses of 3 and 5 confirm the trans-coordination of the new ligands in these square-planar complexes.  相似文献   

8.
Short-bite aminobis(phosphonite) containing olefinic functionalities, PhN{P(OC6H3(OMe-o)(C3H5-p))2}2 (1) was synthesized by reacting PhN(PCl2)2 with eugenol in the presence of triethylamine. The ligand 1 acts as a bidentate chelating ligand toward metal complexes [M(CO)4(C5H10NH)2] forming [M(CO)42-PhN{P(OC6H3(OMe-o)(C3H5-p))2}2}] (M = Mo, 2; W, 3). The reaction between 1 and [CpFe(CO)2]2 leads to the cleavage of one of the P-N bonds due to the metal assisted hydrolysis to give a mononuclear complex [CpFe(CO){P(O)(OC6H3(OMe-o)(C3H5-p))2}{PhN(H)(P(OC6H3(OMe-o)(C3H5-p))2)}] (4). Treatment of 1 with gold(I) derivative, [AuCl(SMe2)] resulted in the formation of a dinuclear complex, [(AuCl)2{PhN{P(OC6H3(OMe-o)(C3H5-p))2}2}] (5) with a Au···Au distance of 3.118(2) Å indicating the possibility of aurophilic interactions. An equimolar reaction between 1 and [Ru(η6-p-cymene)Cl2]2 afforded a tri-chloro-bridged bimetallic complex [(η6-p-cymene)Ru(μ-Cl)3Ru{PhN(P(OC6H3(OMe-o)(C3H5-p))2)2}Cl] (6). The crystal structures of 1-3 and 5 were established by single crystal X-ray diffraction studies.  相似文献   

9.
A novel bifunctionalized arylimido derivative of hexamolybdate, (Bu4N)2[Mo6O17(NAr)2] [Ar = 2,6-(CH3)2C6H3] (1), in which the two 2,6-dimethylaniline groups are bounded to hexamolybdate at the cis positions, was synthesized by a facile reaction of α-octamolybdate with 2,6-dimethylaniline using DCC as a dehydration agent. The existence of strong non-typical C-H?O hydrogen bonds plays an important role in crystal structure stabilization of compound 1. The results of fluorescence spectra show that the formation of a covalent bond between 2,6-dimethylaniline molecule and hexamolybdate could efficiently quench the fluorescence intensity of 2,6-dimethylaniline molecule, with a fluorescence quencher efficiency of 87.7%. Thermal analysis results indicate that two substituted 2,6-(CH3)2C6H3 molecules bonding to the same cluster dissociated at different temperature, in well agreement with the different MoN bond length in compound 1. The electrochemical behavior of modified 1-CPE has been studied in detail. Compared with the conventional polyoxometalate (POM)-modified electrode, 1-CPE presents a merit of remarkable stability over 500 cycles due to the insolubility of the POM nanoparticles, which is especially important for practical applications.  相似文献   

10.
A new aluminoborate, [C5H6N][AlB12O14(OH)12], has been hydrothermally synthesized at 200 °C. The single-crystal diffraction study reveals that it crystallizes in space group C2/c. It consists of aluminoborate clusters [AlB12O14(OH)12] and counterions [C5H6N]+. The aluminoborate cluster contains an Al(OH)6 octahedron as a core that is capped by two raft-like polyborate units [B6O7(OH)6]. These clusters are further interlinked by extensive hydrogen bonding to form a three-dimensional (3D) network, containing large channels along the b-axis, in which the [C5H6N]+ cations are located.  相似文献   

11.
New cluster complex [Mo3SeO3(acac)3(py)3]+ was obtained by ligand substitution in the aqua complex [Mo3SeO3(H2O)9]4+. Crystal structure was determined for [Mo3SeO3(acac)3(py)3]PF6·C6H5CH3. The complex was characterized by 77Se NMR, electrospray mass-spectrometry, and cyclic voltammetry. DFT calculations were used to confirm the assignment of chemical shift and to study Mo-Mo bonding in the cluster core.  相似文献   

12.
The Dawson polyoxotungstate (POM)-based, organometallic ruthenium(II) complex, [{(C6H6)Ru}P2W15V3O62]7−, was synthesized as two materials, i.e. 1 · 2Bu4NCl and 1 · 1Bu4NCl (1 = (Bu4N)7[{(C6H6)Ru}P2W15V3O62]), which contained two positional isomers a and b as major or minor species. In isomer a with the overall Cs symmetry, the (C6H6)Ru2+ group was supported on one vanadium(V) octahedral site (two V-O-V bridging oxygens and one OV terminal oxygen) of the three edge-shared vanadium(V) octahedra (V3 site, B-site) in the Dawson POM-support [1,2,3-P2W15V3O62]9−, whereas in the other isomer b with the overall C3v symmetry, the (C6H6)Ru2+ group was supported on the center of the V3 site in the Dawson POM-support. Material 1 · 2Bu4NCl was prepared by a stoichiometric reaction in CH2Cl2 at ambient temperature of the Dawson POM-support (Bu4N)9[1,2,3-P2W15V3O62] with the precursor [(C6H6)RuCl2]2, whereas material 1 · 1Bu4NCl was prepared by a stoichiometric reaction in CH3CN under refluxing conditions. The temperature-varied 31P NMR spectra revealed that b was thermodynamically more stable thana.  相似文献   

13.
The reaction of 2 equiv. of [Os3(CO)10(MeCN)2] with R-CC-L-CC-R (R = H, L = (C4H2S); R = SiMe3, L = (C4H2S-C4H2S), (C4H2S-C4H2S-C4H2S), (C4H2S)-(C14H8)-(C4H2S)) affords the series of linked clusters [{Os3(CO)10}(HCC(C4H2S)CCH){Os3(CO)10}] (1), [{Os3(CO)10}(Me3SiCC(C4H2S-C4H2S)CCSiMe3){Os3(CO)10}] (2), [{Os3(CO)10}(Me3SiCC(C4H2S-C4H2S-C4H2S)CCSiMe3){Os3(CO)10}] (4) and [{Os3(CO)10}(Me3SiCC(C4H2S)-(C14H8)-(C4H2S)CCSiMe3){Os3(CO)10}] (6) as the major products. The complexes have been characterised by a range of spectroscopic methods and, in the case of 1 and 2 by single crystal X-ray crystallography. The alkyne groups cap the osmium triangles in the expected μ32-||-bonding mode and each triangle is coordinated by nine terminal and one μ2-carbonyl group. Solution UV-Vis spectra of the complexes were similar to those observed for the free ligands consistent with there being little delocalisation between the cluster units and the thiophene groups.  相似文献   

14.
The compound [ArZn(OH)]4 (Ar = 2,4,6-(CF3)3C6H2), formed by aggregation of the hydrolysis product of ArZnCl, has a cubane-like structure at 120 K; this is the first structurally characterised example of such a zinc(II) derivative with a simple aromatic group on Zn, and with the bridges formed by -OH rather than -OR groups. It crystallises as a hemisolvate in the triclinic system , with a single molecule in the asymmetric unit, together with one CHCl3 (or CDCl3) molecule per two molecules of the tetramer.  相似文献   

15.
The meta-diaminoaryl ferrocenes Fc-NCN-H (3) and Fc-CC-NCN-H (5) (Fc = (η5-C5H5)(η5-C5H4)Fe, NCN-H = C6H3(CH2NMe2)2-3,5) can be used as precursors in the preparation of heterobimetallic transition metal complexes of structural type Fc-NCN-MX (NCN = [C6H2(CH2NMe2)2-2,6]; MX = PdCl (7), PtCl (8), PtI (9)) and Fc-CC-NCN-MX (MX = PdCl (11), PdI (12), PtCl (13)), respectively. They are accessible by applying different synthesis procedures, including oxidative addition and metallation-transmetallation processes.Cyclovoltammetric studies show that the ferrocene moieties in 3, 5, 7-9 and 11-13 can reversibly be oxidised. The potential of the Fe(II)/Fe(III) redox couple decreases with increasing electron density at the NCN pincer unit. The use of 8 as a possible (electro)chemical sensor in the detection of SO2 is discussed as well.The solid-state structures of 8 and 13 are reported. The crystals of 8 contain two molecules of 8 in the asymmetric unit. The plane of the C6H2 moiety is with 27.2(3)° and 38.2(3)° tilted towards the C5H4 entity, while in 13 an angle of 45.9(3)° can be found. The d8-electron configured platinum atoms possess a somewhat distorted square-planar surrounding, setup by two Me2NCH2ortho-substituents, the NCN Cipso carbon atom and the chloride ligand.  相似文献   

16.
The compounds W(CO)5P(C6H4-4-CH2CH2(CF2)7CF3)3 (1) and W(CO)5P(CH2CH2(CF2)5CF3)3 (2) were synthesized in order to probe the electronic and physical effects of ligation by perfluorocarbon substituted tertiary phosphine ligands in a W(CO)5L complex. The π-accepting ability of the fluorous phosphines was found to rank with non-fluorous comparators as P(CH2CH2(CF2)5CF3)3 > P(C6H4-4-CH2CH2(CF2)7CF3)3 > PPh3 > P(p-tolyl)3 > P(n-octyl)3. The X-ray crystal structure of W(CO)5P(C6H4-4-CH2CH2(CF2)7CF3)3 shows strong intermolecular association of fluorous components but confirms that the para fluorocarbon subtituents have an insignificant effect on the tungsten coordination environment. Partition coefficients (toluene/perfluoromethylcyclohexane) were measured for compounds 1 and 2.  相似文献   

17.
New silver(I) acylpyrazolonate derivatives [Ag(Q)], [Ag(Q)(PR3)]2 and [Ag(Q)(PR3)2] (HQ = 1-R1-3-methyl-4-R2(CO)pyrazol-5-one, HQBn = R1 = C6H5, R2 = CH2C6H5; HQCHPh2 = R1 = C6H5, R2 = CH(C6H5)2; HQnPe = R1 = C6H5, R2 = CH2C(CH3)3; HQtBu = R1 = C6H5, R2 = C(CH3)3; HQfMe = R1 = C6H4-p-CF3, R2 = CF3; HQfEt = R1 = C6H5, R2 = CF2CF3; R = Ph or iBu) have been synthesized and characterized in the solid state and solution. The crystal structure of 1-(4-trifluoromethylphenyl)-3-methyl-5-pyrazolone, the precursor of proligand HQfMe and of derivatives [Ag(QnPe)(PPh3)2] and [Ag(QnPe)(PiBu3)]2 have been investigated. [Ag(QnPe)(PPh3)2] is a mononuclear compound with a silver atom in a tetrahedrally distorted AgO2P2 environment, whereas [Ag(QnPe)(PiBu3)]2 is a dinuclear compound with two O2N-exotridentate bridging acylpyrazolonate ligands connecting both silver atoms, their coordination environment being completed by a phosphine ligand.  相似文献   

18.
The complexes [(Cy2PCH2PCy2H)CoCl3] (1) and [(Cy2PCH2PCy2O)Co(NO3)2] (2), Cy = cyclohexyl (C6H11), have been prepared and characterized by EPR, UV-Vis, microanalysis and X-ray crystallography. The reaction CoCl2 · 6H2O and dcpm, dcpm = bis(dicyclohexylphosphino)methane, was found to form the monomeric, four coordinate, thermochromic and paramagnetic complex [(Cy2PCH2PCy2H)CoCl3] (1). Of particular interest is the formation of a zwitterion, or inner salt, in which the dangling phosphine adds a hydrogen atom, giving the phosphorus a +1 formal charge. The molecule adopts a pseudo-tetrahedral geometry around the central cobalt atom to which the cyclohexyl groups bind in an equatorial fashion to the phosphine. The reaction of Co(NO3)2 · 6H2O and dcpm in a toluene/methanol/methylene chloride mixture yields the pseudo-octahedral complex [(Cy2PCH2PCy2O)Co(NO3)2] (2). The cobalt is in the +2 oxidation state with one of the phosphorus atoms again having a +1 formal charge. The complex adopts a pseudo-octahedral geometry around the central cobalt atom with the cyclohexyl groups binding in an equatorial fashion to the phosphine similar to [(Cy2PCH2PCy2H)CoCl3].  相似文献   

19.
A new supermolecular assembly crystal, [C6H8N2]6H3[PW12O40]·2H2O (DMB-PWA), was synthesized with phosphotungstic acid (PWA) and 1,2-diaminobenzene (DMB) under hydrothermal conditions and was characterized by Fourier-transform infrared spectra (FTIR) and single-crystal X-ray diffraction analysis. DMB-PWA could effectively catalyze oxidative degradation of chitosan with H2O2 in the heterogeneous phase. The optimum degradation conditions were determined by orthogonal tests as follows: amount of chitosan 1.00 g, 30% (wt %); H2O2, 3.0 mL; dosage of catalyst, 0.06 g; reaction temperature, 85 °C; and reaction time, 30 min. The water-soluble chitosan with a viscosity-average molecular weight (Mv) of 4900 was obtained under the optimum degradation conditions and was characterized by FTIR, ultraviolet-visible diffuse reflection spectra (UV-vis DRS), and X-ray powder diffraction analysis.  相似文献   

20.
Two new zincophosphites [C6H14N2]0.5[Zn(H2PO3)2] 1 and [C4H12N2]0.5[(CH3)2NH2][Zn2(HPO3)3] 2 have been solvothermally synthesized in mixed solvents of N,N-dimethylformamide (DMF) and 1,4-dioxane (DOA), respectively. Single-crystal X-ray diffraction analysis reveals that compound 1 exhibits a neutral inorganic chain formed by ZnO4 and HPO2(OH) units. Interestingly, the left- and right-handed hydrogen-bonded helical chains are alternately formed via the hydrogen-bonds between two adjacent chains. Compound 2 exhibits a layer structure with 4- and 12-MRs formed by ZnO4 and HPO3 units, in which two kinds of organic amine molecules both act as countercations to compensate the overall negative electrostatic charge of the anionic network.  相似文献   

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