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IntroductionThe design and the synthesis of new chiral ox-azoline[1,2 ] and C2 symmetric bis( oxazoline) ligandsand the application of their metal complexes inasymmetric catalytic reactions have inspired manyscientists to great exertions in recent years[3— 8] .Our interest has been focussed on the studies ofenantioselective transition metal catalysis ofhetero-cyclic ligands[9— 11] . In the synthesis of our new de-signed ligands,what is crucial is to select a rigidcyclic backbone. Bis( oxazo…  相似文献   

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1INTRODUCTIONTherehasbeenconsiderableattentionfocusedonthestudyofpalladiumcomplexinorganicsynthesis,catalyticprocesses,chemicalreactivity,spectroscopyandstructuralanalysisandfunctionalmaterials[1].Manypalladacycleshavebeenappliedinthepreparationofliquid-crystallinecomplexes[2],andsomeofthemshowantitumoractivity.Theincreasingimportanceofsuchcyclo-organometalliccomplexleadsustoinvestigatethecyclicPdcomplexeswithenhancedchemicalandthermalstability,fromwhichdetailedspectroscopicandstructuralc…  相似文献   

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A range of rare earth metal complexes of 2-mercaptopyridine N-oxide (Hmpo) have been synthesized, and studied by elemental analysis and IR spectroscopic technique. Crystal structure of Dy(mpo)3(DMSO)2 (DMSO = dimethyl sulfoxide) has been determined. The complex crystallizes in the triclinic system, space group Pī with lattice parameters: a = 9.602(3), b = 9.803(3), c = 15.498(5)A, α= 89.51(1), β= 85.73(1), γ= 62.99(1)°, Dc = 1.787 g/cm3, C19H24N3O5S5Dy, Mr = 697.21, Z = 2, F(000) = 690, μ = 3.321mm-1, the final R = 0.0237 and wR = 0.0587 for 4116 reflections with I>σ2(I). The coordination number of dysprosium Ⅲ is eight, and its coordination geometry is a somewhat distorted square antiprism with O(3), O(4), O(5), S(3) and O(1), O(2), S(1), S(2) at the tetragonal bases (dihedral angle between their mean planes is 2.9(1)0). Around the Dy atom, three five-membered ring planes (Dy, O, N, C, S) make the dihedral angles of 74.42, 11.31 and 83.72, respectively.  相似文献   

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李媛  金声 《结构化学》1999,18(5):331-334
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1 INTRODUCTION The lanthanide amide complexes are excellent synthetic precursors for lanthanide derivatives, par- ticularly in the reactions involving protonic rea- gents[1]. A few types of lanthanide amide complexes, from homoleptic three- to four-coordinate, have been known for some time[2~4]. Recently, we begin to examine the utility of amide with less steric bulk, such as diphenylamide and diisopropyamide, as li- gands to synthesize homoleptic lanthanide amide complexes. For diphen…  相似文献   

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The title compound (C22H32.5ClCoN6O8.25,Mr=607.42)crystallizes in the orthorhombic system,space group c222 1 with a=11.320(2),b=20.933(4),c=23.936(5)A,V=5672(2)A^3,Dc=1.423g/cm^3,Z=8,μ(MoKα)=0.754mm^-1,F(000)=2532,R=0.0512 and wR=0.1190,There are eight complex molecules [Co(C4H6N2O2)(C4H8N2O2)(C7H9N)2]ClO4.0.25H2O of C2 crystallographic symmetry in a unit cell,including two crystallographically independent molecules,in which different orientations of the MePhNH2 groups are found.Two MephNH2 groups are in trans position for molecule A,and cis for B.The central metal atom is in a distroted octahedral environment.The hydrogen bonds of O-H(oxime)…O and N-H(p-aminotoluene group)…O construct an one-dimensional chain along the c axis in the title compound.  相似文献   

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Synthesis and Crystal Structure of 3,4—Bis(azidoacetamino)furazan   总被引:1,自引:0,他引:1  
1INTRODUCTIONDuringthepastthreedecades,1,2,5-oxadiazole(furazan)hasbeenstudiedintheN.D.ZelinskyInstituteofOrganicChemistry[1,2],anditwasfoundthatthearomaticityoffurazanringusuallyincreasesthethermalstabilityofitsderivativesandtheplanarityoftheringprovidesthemwithhighdensity.TheweaknessoftheNObondsinfurazanwassuggestedbyananalysisofitsmass-spectrum[3].Itagreeswiththeresultsoftheresonanceformsoffurazan,whichiscalculatedbySaegebrath[4].Thereby,whenthechloroacetaminogroupwasintroducedintot…  相似文献   

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The title compound, ( )-O-phenyl cyclophosphorodiamidate (C28H33N202P, Mr=460.53), has been synthesized and characterized by 31p NMR, 1H NMR and elemental analysis. X-ray diffraction analysis at 273(2) K indicates that it belongs to orthorhombic system, space group P212121 with a=11.518(4), b=13.449(4), c=16.539(5)A, V=2562(1)A3, Z=4, Dc=1.194g/cm3, F(000)=984 and μ(MoKα)=0.134mm-l. The structure parameters were refined by full-matrix least-squares on F2 to R=0.0459 and wR=0.0640. The flack χ parameter is 0.03(10), and the absolute configuration of the phosphorus atom in the title compound is S.  相似文献   

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The tetra(o-cyanobenzyl)tin compound has been synthesized by the reaction of cyanobenzyl chloride with tin, and its molecular structure was characterized by elemental analysis, IR spectra, ^1H NMR and X-ray diffraction. Crystal data for this compound: monoclinic, space group C2/c, Mr = 583.24, a = 1.9629(2), b = 1.05967(13), c = 1.41249(18) nm, β= 118.180(2)^o, V = 2.5898(5) nm^3, Z = 4, Dc =1.496 g/cm^3, μ(MoKa) = 1.015 cm^-1, F(000) = 1176, R = 0.0189, wR = 0.0497 (observed reflections with I 〉 20(I)) and R = 0.0218, wR = 0.0513 (all reflections). The molecular structure adopts a distorted tetrahedral geometry around the tin atom. The Sn'"N weak interaction between the Sn and N atoms of cyano forms an intermolecular H-bonding, and the bond length is 0.3570 nm; the interaction between hydrogen of methylene and benzene ring of benzyl forms C-H…C with its bond length of 0.2817 nm; and the interaction among hydrogen of benzene ring and carbon of cyano forms Ph-H…C bond (0.2897 nm) Of the σ…π interaction. A 3D chain structure is formed by the above weak intermolecular interactions.  相似文献   

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The ferrocenyl compound,N-phenylbis(ferrocenecarboxyl)imide (C28H23NO2Fe2,Mr=517.17),was synthesized and structurally characterized by means of X-ray single-crystal dif-fraction. It crystallizes in monoclinic,space group C2/c with a=21.374(14),b=10.430(7),c= 10.741(7) ,β=114.184(8)°,V=2184(2) 3,Z=4,Dc=1.573 g/cm3,F(000)=1064,μ(MoKα)= 1.355 mm–1,T=291(2) K,the final R=0.0548 and wR=0.1437 for 1524 observed reflections with I > 2σ(I). In this compound,the nitrogen atom links two ferrocenyl groups and one phenyl group forming a novel imido derivative.  相似文献   

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A new dinuclear La(Ⅲ) complex [La2(4-cba)4[H(4-cba)2]2(phen)2(H2O)4] (4-Hcba = 4-cyanobenzoic acid and phen = 1,10-phenanthroline) 1 has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100 ℃ and structurally characterized by singlecrystal X-ray diffraction. Crystallographic data: C88H58La2N12O20, Mr = 1881.28, triclinic P1, a = 7.518(3), b = 17.033(6), c = 17.551(6)A, α = 115.333(4), β = 92.9910(10), γ = 99.366(5)°, V = 1985.3(12)A^3, Z = 1, Dc = 1.574 g/cm^3, F(000) = 944 μ = 1.145 mm^–1, the final R = 0.0281 and wR = 0.0686 for 6708 reflections with Ⅰ 〉 2σ(I). In 1, two nine-coordinated La(Ⅲ) ions are connected by two 4-cba ligands in a syn-syn bidentate coordination mode, and the other six 4-cba ligands terminate the La(Ⅲ) ions, resulting in an isolated dinuclear structure. Two different types of intramolecular hydrogen bonds, asymmetrical O-H…O and symmetrical O…H…O, exist in the crystal. The title complex molecules are connected through hydrogen bonds and weak π-π stacking interactions to generate a 2-D layered network. The thermogravimetric analysis of 1 has also been discussed.  相似文献   

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A new lanthanum complex, (H3O)2[La(C7H3NO5)2(H2O)212.3(H2O) or (HaO)E[La(HChel)2(HEO)E]2.3(H2O) 1 (H3Chel = 4-hydroxypyridine-2,6-dicarboxylic(chelidamic) acid), has been prepared by the hydrothermal reaction, and its crystal structure was determined based on single-crystal diffraction data. Compound I crystallizes in triclinic, space group Pi with a = 9.6939(19), b = 10.176(2), c = 11.502(2)A, α = 111.52(3), β = 93.74(3), γ = 103.33(3)°, V = 1013.0(3)A3, Dc = 1.912 g/cm3, Z = 1, Mr = 1166.40, p = 2.188 mm-1, 2(MoKa) = 0.71073 A and F(000) = 574. The final R = 0.0342 and wR = 0.0737 for 4080 observed reflections with I 〉 2σ(I), and R = 0.0429 and wR = 0.0772 for all data. Compound 1 contains two lanthanum ions, four chelidamic acid ligands, four coordinated water molecules, two hydroniums, and three discrete water molecules. The LaⅢ atom is ten-coordinated by four oxygen and two nitrogen atoms from two tridentate chelating chelidamic acid ligands, two carboxylic oxygen atoms from an adjacent chelidamic acid ligand and two coordinated water molecules, leading to a distorted dodecahedral geometry. A three-dimensional network is formed by H-bonds.  相似文献   

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