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1.
The hydroformylation of hexene-1 catalyzed by Rh_4 (CO)_12 and 〔Rh(CO)_2Cl〕_2 andthe effects of solvents (benzene, n-heptane and THF) and PPh_3 on the activity andselectivity of the catalysts were studied.The results indicated that the activity of Rh_4(CO)_(12) decreased with increasing solventpolarity and it did not change appreciably with addition of PPh_3 when the molar ratioPPh_3/Rh_4(CO)_(12)≤4. Thc activity of Rh_4(CO)_(12) was over twice as large as that of〔Rh(CO)_2Cl〕_2 when calculated according to the number of moles of rhodium clusters inbenzene without PPh_3, but the activities of both Rh_4(CO)_(12) and 〔Rh(CO)_2Cl〕_2 wereabout the same when calculated according to the number of rhodium atoms. It is suggestedthat the clusters probably dissociated into the similar active rhodium mononuclear speciesunder the reaction conditions and the species formed a cluster similar to Rh_4(CO)_(12) againwhen the conditions were reduced to the ambient temperature and pressure.  相似文献   

2.
A series of new complexes of formula Ln_2[H_2(BAA)_2en]_3nH_2 Otwhere Ln- La,Pr, Eu, Cd, Dy, Er, Yb, n-1-4) have been prepared by the reaccLon of lanthanideions with acycllc compartmental ligand X, N'-bis(benzoylacetylacetone)ethylenediamine(H_4(BAA)_2 en) in methanol. IR and UV spectra, as well as TC DAT analysis prove thatthe ligand and the Lanthanide ions have coordinated. The coordination number is 12and the complexes may be of double sandwiched structure.  相似文献   

3.
The synthesis and ~1H NMR, ESR, IR, UV spectra of binuclear bridged complex μ-4,4-bipy[VO-(acac)_2]_2 are reported in this paper. The structure of the complex is discussed using measured spectral parameters.It is deemed that 4,4-bipy as a bridge passing through its two N atoms combined respectively with two V atoms at its sixth position, forming a binuclear bridged complex.The spectra are explained satisfactorily and coefficients of molecular orbitals,β_1,β_2 and 8_m,are calculated from the results of ESR and UV etc.  相似文献   

4.
Functional monomer (MP)_2PT having tertiary aromatic amino group was systhesized from the reaction of N, N-di (2-hydroxypropyl)-p-toluidine with 2-methyl acryloyl chloride. In the presence of organic peroxide, the radical polymerization of (MP)_2PT in toluene took place. The kinetics of (MP)_2PT polymerization and the ESR spectra of LPO-(MP)2PT-MNP systems were determined respectively.  相似文献   

5.
<正> INTRODUCTION. We have previously reported the mass spectra of a single MoFe_3S_4 cubane-like cluster compound (Et_4N)MoFe_3S_4(Et_2NCS_2)_5. Its analogue MoFe_3S_4(C_4HaNCS_2)_5 having the same core structure has rently been synthesized and characterized structurally. In this paper, the results of its mass spectra investigation using an electron impact (EI) ionization mass spectrometer are offered and identified by metastable technique, isotopic  相似文献   

6.
IR and NMR spectra of novel bionics insecticide—C_5NS_4O_6H_(12)Na·H_2O have been studied. The molecular and crystal structures of the compound also have been determined. The compound crystallizes in the monoclinic space group C_(2h)~5, - P2_1/n with α= 8.0972. (9) , b =16.262(4), c = 10.370(3), β= 94.26(2)° and z = 4.The result shows that N atom in this compound captures a proton to form HN~ group, Na~ is in statistical disorder. Therefore, the structural formula of tho compound is (CH_3)_2HN~ —CH(CH_2S_2O_3~-)_2·1/2 (Na~ )_2·H_2O.  相似文献   

7.
The ESR spectra of VO(NCS)_n~((2-n) ) complexes have been studied in this paper. It is shown that four complexes ions of various compositions, VO(NCS)~ , VO(NCS)_2, VO(NCS)_3~- and VO(NCS)_4~(2-), are formed in glyeol-water-mixed media. The parameters of the ESR spectra have been determined. We established a linear correlation between the hyperfine coupling constant and the coordination number n. n=117.66-3.41n (gauss). All the stability constants for various complexes formulated as VO(NCS)_n~((2-n) )(n=1,2,3,4) have been calculated from the ESR spectra, log K_1=2.15; log K_2=1.55; log K_3=0.87; log K_4=0.22. K_3and K_4 have not been reported in literature up to now.  相似文献   

8.
<正> Introduction. A series of trinuclear molybdenum clusters has been synthesized and identified. Most of them have almost the sameMo-Mo distance. We have synthesized another kind of trinuclear molybdenum complex which has different Mo-Mo distances and can be comsidered as composed of the complex (Mo_2O_2S_2(py)_4)~2+ and the molbdenic ion (MoO_4)~2-. This paper reports the synthesis and structure of the title compound.  相似文献   

9.
The single crystal of two-electron heteropoly blue with Si as the heteroatom and α-Keggin structure K_2H_4SiMo(Ⅴ)_2Mo(Ⅵ)_(10)O_(40)·12H_2O was obtained by electrolytic reduction. It crystallizes in a triclinic system with space group P , Mr=2117.73, a= 13.702(4), b=14.107(3), c=14.184(2) ; α=119.27(1), β=93.14(2), ;γ=110. 3(2)°, V=2154.29~3, Z=2, F(000)=1999, μ=36.39cm~(-1), Dc=3.26 g/cm~3. Final R factor is 0.0515. Mo(Ⅴ) is situated in two different edge-shared Mo_3O_(13) groups. The heteropoly blue was characterized by IR, UV, polarography, X-ray photoelectron spectra and ESR. All the results show that the structure of the heteropoly anion with Keggin structure remains unchanged basically in the process of reduction.  相似文献   

10.
By the reaction of bidentate ligand 1,1'-bis(diphenylphosphino)-ferrocene (dppf) with MoCl_4(CH_3CN)_2, a novel bonding type complex (MoCl_4)2_· (dppf) was synthesized and characterized by elemental analyses, ~(31)p-NMR, IR and electronic spectra, TG and ICP-AES. Structure of the title complex was proposed.  相似文献   

11.
The characteristics of the LB films of Schiff base aluminium(Ⅲ), tris(2-hydroxy-5-nitro-N-dodecyl-benzylideneaminato) aluminium(Ⅲ)[Al(TA12)_3], were studied. The surface pressure-area(π-A) isotherm of Al(TA12)_3 in the pure water subphase was investigated. The molecular area, 0.48 nm~2, is one-third of the expected value that indicates the formation of an aggregate. The Langmuir-Blodgett(LB) films of Al(TA12)_3 were transferred and characterized. The UV-Vis spectra and the AFM image both confirmed that the J-aggregates formed. The polarized UV-Vis spectra indicated that the complex plane had to be oriented with an angle of about 30° to the substrate surface. The IR spectra suggested that the complexation took place between aluminium ions and the oxygen atoms of the ligand rather than the nitrogen atom.  相似文献   

12.
The supported catalysts for propylene polymerization were prepared by milling Mg (OEt)_2 with EB (ethylbenzoate) and treating with TiCl_4 solution. When TiCl_4/(Mg(OEt)_2/EB) (mol.) ratio was increased, decrease in contents of-OEt and Ti of the catalysts was observed, while the content of EB increased. It is proved by analyses of IR, X-ray and XPS that during co-milling Mg(OEt)_2 with EB no reactions have taken place. But after treatment with TiCl_4 solution, Mg(OEt)_2 converts into MgCl_2 and EB coordinates on the resulting MgCl_2 carrier, a surface complex forms.The activity of catalysts,isotacticity and vicosimetric molecular weight of polypropylene increase with the decrease of the content of ethoxyl group. The kinetic curves of propene polymerization obtained with present catalysts system display decay curves. It is found from the triad tacticity calculated from the expanded spectra of methyl carbon region that, ethoxyl group in catalyst has an effect on the configuration of polymer chain.  相似文献   

13.
<正> INTRODUCTION. The complexes of some transition metals with plant growth regulators still have growth-regulating activity. For example the copper(Ⅱ) chelates of N-phenyl thalaminic acid derivatives are this type complexes. We have synthesized complex of Cu(Ⅱ) with β-naphthoxyacetic acid which has the action of stimulating plant growth. The crystal structure of Cu_2(β-C_(10)oH_7OCH_2COO)_4(DMF)_2 has been determined.  相似文献   

14.
The reaction of Fe_2(μ_3-Te)_2(CO)_9 with Mo_2(CO)_6(η~5-C_5H_5) affords the title compound. Its X-ray analysis shows a butterfly structure for the Mo_2Fe_2 core; the two molybdenum atoms occupy the hinge with a Mo—Mo bond distance of 2.819 and the two iron atoms are on the tops of the wings with an average Mo—Fe bond distance of 2.932(2). Each molybdenum is bonded to a Cp ring, and three CO ligands are terminally bonded to each iron atom. One tellurium atom quadruply bridges Mo_Fe_2 with Mo—Te(μ_4)=2.625(2). and Fe—Te(μ_4)=2.713(2). Two tellurium atoms triply bridge the two triangular Mo_2Fe faces with Mo—Te(μ_3)=2.678(1) and Fe—Te(μ_3)=2.513(3). The molecule has C_(2v) symmetry and a bicapped triangle bipyramidal skeleton. Crystallographic parameters are as follows: space groupImm2(orthorhombic), a=14.562(3), b=10.391(1), c=7.139(4), V=1080.2(i)~3, Z=2, ρ(cald)=1.819g·cm~(-3). The final R factor was 2.2% for 620 independent reflections(I>2σ(I)).  相似文献   

15.
The complexes, Nd(TTA)_4·HP and Er(TTA)_4·HP, have been prepared, and their UV-VIS-NIR absorption spectra measured. The matrix element expressions with J=1/2—15/2 of f~3 and f~(11) configurations in D_4 symmetry field were derived with the Double Sphere Coordination Point Charge Field Model. And the influence of change in symmetry of the complex unit REO_8 on splitting of their levels was discussed. Based on theoretical calculations, the absorption peaks in the spectra were assigned.  相似文献   

16.
The mixed ligand complex of cobalt with dibutylphosphate (HDBP) and pyridine has been synthesized. Elemental analysis yields the result that the formula of this compound is Co(DBP)_2·3Py·CHCl_3 (Py=pyridine). The thermal analsyis, visible spectra and magnetic properties of it have been studied as well. Single crystal structural analysis shows that the crystal is triclinic with space group P and the unit cell parameters are as follows:a=14.490(10), α=90.37(4)°,b=15.721(7), β=96.04(5)°,c=20.109(12), γ=105.63(4)°.The final R factor is 0.0773. Two Co atoms are connected by two bridging DBP groups to form a dinuclear molecule [Co(DBP)_2·3Py]_2 which has a C_s, symmetry. Each cell contains two dinuclear molecules and four chloroform molecules. The cobalt is coordinated in an octahedral arrangement by three oxygen atoms and three nitrogen atoms, of which one oxygen atom comes from a monodentate DBP group, two oxygen atoms from two bridging DBP groups, and the three nitrogen atoms from the three pyridi  相似文献   

17.
The perovskite type of compound [n-C_(11)H_(23)N_3]_2ZnCl_4(abr.C_(11)Zn)exhibits two solid-solid phasetransitions at T_(c1)=298.7 K and T_(c2)=360.1 K.A temperature dependence study of Raman spectra of C_(11)Znprovides the evidence of occurence of the structural phase transition related to the dynamics of thealkylammonium ions.The room temperature phase is ordered and contains the all-trans alkyl chains.Theintermediate temperature phase presents a partial conformational disorder and liquidlike state of allconformational disorder occurs at high-temperature phase.  相似文献   

18.
<正> INTRODUCTION. Resently a series of M2-type trinuclear Mo clusters with the formula {Mo_3(μ-Y)(S_2)_3[S_2P(OEt)_2]_2]_3}X, (Y=O or S; X=Cl or I) have been synthesized by our research group through either the reduction of the higher valence Mo(V) compounds or the oxidation of the middle valence Mo(Ⅲ) species. In this paper we report a novel type of cluster cation  相似文献   

19.
Dicyanide building block cis-Fe(phen)_2(CN)_2 and [Mn~Ⅲ(salen)](ClO_4) have been used to design and synthesize a cyanide-bridged complex, resulting in a heterobimetallic one-dimensional(1D) zigzag chain complex 1, [cis-Fe(phen)_2(CN)_2Mn(salen)](PF_6)(phen =1,10-phenanthroline, salen=N,N?-ethylenebis-(salicylideneaminato) dianion). Single-crystal X-ray diffraction analysis shows complex 1 crystallizes in the monoclinic P2_(1/c) space group and the asymmetric unit contains one [-NC-Fe(phen)_2(μ-CN)-Mn~Ⅲ-(salen)-]~+ cation and one PF_6~- anion. In the cationic structure of 1, each Fe~Ⅱ(phen)_2(CN)_2 connects two [Mn~Ⅲ(salen)]~+ with two cyanide groups in a cis-conformation, and in turn each [Mn~Ⅲ(salen)]~+ unit links two Fe~Ⅱ(phen)2(CN)_2 building blocks in a trans-conformation, resulting in a 1D [-NC-Fe~Ⅱ-CN-Mn~Ⅲ-]n chain. Furthermore, the electronic absorption spectra and electrochemical and magnetic properties of complex 1 have also been studied.  相似文献   

20.
<正> INTRODUCTION. In the reported crystal structures of di(μ-X)(X=O,S)-bridged oxodimolybdates (Ⅴ), the local, symmetric array of donor atoms linked to the Mo atoms is well known. The title compounds (QH)_3[Mo_2O_4(COO)-(NCS)_4]-H_2O(Ⅰ) and (QH)_3[Mo_2O_4(CH_3OH)(NCS)_5](Ⅱ), in which the environments  相似文献   

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