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1.
Two new uranyl β-diketonate complexes [UO2(DBM)2(DEDPU)] (1) and [UO2(PMBP)2(DEDPU)](CH3C6H5)0.5 (2), (HDBM?=?dibenzoylmethane, HPMBP?=?1-phenyl-3-methyl-4-benzoyl-5-pyrazolone, DEDPU?=?N,N′-diethyl-N,N′-diphenylurea) were synthesized and characterized. The coordination geometries of the uranyl atoms in 1 and 2 are distorted pentagonal bipyramidal, coordinated by one oxygen atom of DBDPU molecule and four oxygen atoms of two chelating DBM molecules in 1 and PMBP molecules in 2.  相似文献   

2.
1 INTRODUCTION The azine derivatives are useful compounds because of their special properties. On the one hand, the azines and ,-dichloro-azines are very impor- tant intermediates[1, 2] for synthesizing s-tetrazines which have some peculiar properties, s…  相似文献   

3.
1INTRODUCTIONSeveraldiorganotinchloridesformhydrateswhosecoordinatedwatermoleculesinteractviahydrogenbondswiththecrownethers.Thepolyether,18-crown-6,affordscomplexeshavingtheformulationof[RRSnCl2H2O]2C12H24O6(e.g.,R=R?=CH3[1];R=R?=C6H5[2];R=CH3,R?=C6H5[3]);atin-chlorinebridgeraisesthecoordinationnumberofthemetalatomstosix.Withtriphenyltinchlorideinplaceofthediorganotindichlorides,theouter-spherecoordinationcomplexexistsasanaquachlorotriphenyltinentitythatinteractswiththecrownethe…  相似文献   

4.
1 INTRODUCTION The tris(ethylenediamine) cobalt (Ⅲ) complex in which there are L and D configurations is one of the very interest cations due to the chirality among research complexes and the characterization of reaction on the ion-pair charge-transfer transitions. It has been mentioned in a lot of examples on the chirality and the structure, such as [L-Co(en)3]- [?Co(edta)]2Cl?0H2O[1], [(+)DCo(en)3]Cl3稨2O[2], [(+)-Co(en)3?-)-Cr(en)3]Cl?.1H2O[3], [()-Co(en)3] (SCN)3[4], [(+)D…  相似文献   

5.
In the crystal structures of the centrosymmetric isostructural co-crystals, bis[aqua- hlorotriphenyltin]dihydrate(1,4,7,10,13,16-hexacyclooctadecane-bis[aquachlorotriphenyltin(Ⅳ)]a 1,4,7,10,13,16-hexacyclooctadecane (3/1) 1 and bis[aquatrifluoroacetatotriphenyltin] dihydrateb 1,4,7,10,13,16-hexacyclooctadecane-bis[aquatrifluoroacetatotriphenyltin(IV)](1,4,7,10,13,16- hexacyclooctadecane(3/1) 2, the crown ether interacts with the triphenyltin unit through both the coordinated and lattice water molecules in one molecular entity, but only through the coordinated water molecule in the other. The tin atoms are five-coordinate in trans-trigonal bipyramidal environments. Compound 1 is refined on 204 variables and 4665 I > 3((I) reflections to R = 0.055, and compound 2 on 233 variables and 5721 I > 3((I) reflections to R = 0.052. For crystal 1: C192H244Cl8O38Sn8, fw = 4392.99, trigonal, R, a = 27.391(1), c = 23.007(1) A。, V = 14948(1) A。3, Z = 3, Dc = 1.464 g/cm3, F(000) = 6708 and μ = 1.162 mm-1; and for 2: C208H244F24O54Sn8, fw = 5013.55, trigonal, R, a = 28.775(1), c = 23.289(1) A。, V = 16699(1) A。3, Z = 3, Dc = 1.496 g/cm3, F(000) = 7620 and μ = 0.978 mm-1.  相似文献   

6.
The title compound bis[α-chloro-(o-chloro-benzylidene) hydrazine] (C14H8Cl4N2, Mr = 346.02) has been prepared, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 10.777(2), b = 6.456(2), c = 10.988(3) A, β = 90.48(2)o, V = 764.5(3) A3, Z = 2, Dc = 1.503 g/cm3, F(000) = 348 and μ(MoKα) = 0.763 mm-1 (λ = 0.71073 A). The structure was refined to R = 0.0793 and wR = 0.2398 for 1694 observed reflections with I > 2σ(I). The results of crystal structure determination show that both C(7) and C(7)a are of sp2 hybridization and there exists electronic conjugation in the aza-diene of -C=N-N=C.  相似文献   

7.
Reaction of triphenylstibine with furfuraloxime in the presence of hydrogen peroxide in water-ether solution forms -oxobis[triphenyl(furfuraloximato)antimony(V)] in 90% yield. This complex has a dimeric structure in which two antimony atoms are bound with the bridge oxygen atom and two bridge oxime groups coordinating the metal atom by the oxygen as well as by the nitrogen atoms to form bicyclo[2.2.1]heptane fragment. SbOSb angle is 125.5(3)°, the bonds between the antimony atom and the bridge oxygen atoms [1.957(6) and 1.946(5) Å] are shorter than with the oxygen atoms of oxime groups [2.146(6) and 2.148(6) Å].  相似文献   

8.
IntroductionSelf assemblyofcoordinationpolymersfromthebasicbuildingblocksisofconsiderableinterestduetotheirintrigu ingdiversearchitecturesandpotentialapplicationsincatalysisandadvancedmaterialssuchasmagnetic ,optic ,andelec tronicmaterials .1 4 Thearchitecturesofcoordinationpolymerscanbereliablypredicted ,sincepreviouslyknownmetalcoor dinationenvironmentsarepropagatedintoone ,two ,andthree dimensionalmotifswithrigidmultitopicorganic“spac er”ligands .Thereactionofametalcomplexexhibitingtwovac…  相似文献   

9.
The x-ray structural study showed that [N-(2-thienylidene)]benzhydrazide does not form a crystal hydrate. The molecules in the crystal are loosely packed and joined by linear chains of intermolecular hydrogen bonds (IHB),. Like the previously investigated [N-(furfurylidene)] benzhydrazide, [N-(2-thienylidene)]benzhydrazide crystals were sensitive to UV radiation. The similarity in the structure of these compounds confirms the hypothesis that intermolecular N O phototransfer of a proton along the IHB chain can take place efficiently in loose structures in the noncrystal hydrates of the compounds investigated, in contrast to the previously studied crystal hydrates.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 87–90, January, 1991.  相似文献   

10.
1 INTRODUCTION Interest in vanadium in the physiology and biochemistry has promoted enormously in recent years. Vanadium is known to exist in alternative nitrogenase metalloenzyme systems fixing nitrogen. It is also found to participate in biological processes exhibiting mitogenic behavior and enzyme inhi- bition[1]. Up to date, several crystal structures have been reported about vanadium with carboxylic or polycarboxylic acid[2, 3]. However, very few struc- tures of vanadium complexes …  相似文献   

11.
The cyanate-bridged cyclopalladated compound [Pd(N,C-dmba)(-NCO)]2 (1)(dmba = PhCH2NMe2) reacts in CH2Cl2 with 2,3-lutidine (2,3-lut), 3,4-lutidine (3,4-lut), 2,2-bipyridine (2,2-bipy) and 4,4-bipyridine (4,4-bipy), to give [Pd(N,C-dmba)(NCO)(2,3-lut)](2), [Pd(N,C-dmba)(NCO)(3,4-lut)](3), [{Pd(N,C-dmba)(NCO)}2(-2,2-bipy)]· CH2Cl2 (4) and [{Pd(N,C-dmba)(NCO)}2(-4,4-bipy)]· CH2Cl2 (5), respectively. The compounds were characterized by elemental analysis, i.r. and n.m.r. spectroscopy and also by t.g.a. The i.r. spectra of (2–5) display typical bands of monodentate N-bonded cyanate groups, whereas the n.m.r. data of (4) are consistent with the presence of a bridging 2,2-bipyridine ligand. Complex (4) decomposes slowly in acetone. One of the products formed, [Pd(H2CCOMe)Cl(2,2-bipy)](6), was characterized by X-ray diffraction. As inferred from the t.g.a., the thermal stability decreases in the order:[{Pd(N,C-dmba)(NCO)}2(-4,4-bipy)].CH2Cl2 (5) > [Pd(N,C-dmba)(2,3-lut)(NCO)](2)=[Pd(N,C-dmba)(3,4-lut)(NCO)](3) > [{Pd(N,C-dmba)(NCO)}2(-2,2-bipy)]· CH2Cl2 (4). According to thermal analysis and X-ray diffraction patterns compounds (2–3) decompose into metallic palladium Pd(0), whereas (4–5) decompose with the formation of PdO. The X-ray crystal and molecular structure of [Pd(N,C-dmba)(NCO)(2,3-lut)](2) was determined. The lutidine unit is perpendicular to the coordination plane.  相似文献   

12.
Trifluoromethylation of [AuF3(SIMes)] with the Ruppert–Prakash reagent TMSCF3 in the presence of CsF yields the product series [Au(CF3)xF3−x(SIMes)] (x=1–3). The degree of trifluoromethylation is solvent dependent and the ratio of the species can be controlled by varying the stoichiometry of the reaction, as evidenced from the 19F NMR spectra of the corresponding reaction mixtures. The molecular structures in the solid state of trans-[Au(CF3)F2(SIMes)] and [Au(CF3)3(SIMes)] are presented, together with a selective route for the synthesis of the latter complex. Correlation of the calculated SIMes affinity with the carbene carbon chemical shift in the 13C NMR spectrum reveals that trans-[Au(CF3)F2(SIMes)] and [Au(CF3)3(SIMes)] nicely follow the trend in Lewis acidities of related organo gold(III) complexes. Furthermore, a new correlation between the Au−Ccarbene bond length of the molecular structure in the solid state and the chemical shift of the carbene carbon in the 13C NMR spectrum is presented.  相似文献   

13.
Two new copper(II) azido complexes, namely bis-(tetraethylammonium)[tetraazidocuprate(II)] (1) and catena-di--1,1-azido-[di--1,1-azido-bis-(2,4-dimethylpyridine)dicopper(II)] (2), have been prepared and characterized by spectroscopic and crystallographic methods. Complex (1) consists of isolated NEt+ 4 cations and [Cu(N3)4]2– anions. The site symmetry around the copper atom in the anion is 4/m. Complex (2) features a 1 D chain structure, five coordinated square pyramidal copper(II) atoms with both azides functioning as -1,1-bridges. The i.r. spectra reveal that both complexes contain asymmetric azido ligands. The solid and solution electronic spectra of (1) and (2) show very strong absorption bands in the visible region associated with N 3 CuII charge-transfer transitions. The e.p.r. spectra of powder samples and solutions at room temperature were recorded and discussed.  相似文献   

14.
Crystals of [Cu(DAF)(H2O)]BF4(I) and [Cu(DAF)(ClO4)] (II) (DAF is diallyl formamide) were synthesized by an alternate-current electrochemical method, and their structures were determined (MoK radiation, 1247 and 859 independent reflections with I 2(I), R= 0.043 and 0.032 for Iand II, respectively). The complexes crystallize in space group P21/n, Z= 4. For I, a= 10.782(3) Å, b= 12.096(5) Å, c= 9.185(3) Å, = 103.62(3)°, and V= 1164.2(7) Å3; for II, a= 10.064(3) Å, b= 10.753(6) Å, c= 10.002(3) Å, = 87.52(4)°, and V= 1081.4(8) Å3. The copper atom in structures Iand IIcoordinates both C=C bonds in one DAF molecule and oxygen atom of the amide group of another DAF molecule, as well as an oxygen atom of H2O (in I) or ClO4(in II) in the axial position. The uncommon behavior of the anions in structures Iand IIis explained by their different values of Pierson hardness.  相似文献   

15.
16.
1INTRoDUCTIONMacrocycliccoordinationcomPOundshavebeenwidelyinvestigatedinthepastdecadesbecauseoftheirrelationshiptocomplexesofbiologicalsignificancesuchasthePorphyrinsandcorrins(lJ.Structuresofmanymacrocycliccompoundshavebeenre-ported,especiallythecompoundscontainingN4macrocyclicligands"'.However,toourknowledge,onlyafewcrystalstructuresofcomplexbimetallicsaltscontainingmacrocyclicligandshavebeendeterminedbyX-raydiffractionmethod.Inthispa-per,werePortthesynthesisandstructureofthetit1ecom…  相似文献   

17.
A new coordination compound [Co(Pht)(2-MeIm)2] (I), where Pht2–is the deprotonated radical of o-phthalic acid (H2Pht) and 2-MeIm is 2-methylimidazole, was synthesized. Its structure was established using X-ray diffraction analysis. The crystal is orthorhombic: space group Pca21, a= 15.350(3), b= 7.957(2), c= 13.997(3) Å, (calcd.) = 1.505 g/cm3, and Z= 4. The tetrahedral coordination of the Co(II) atom includes two N atoms of two 2-methylimidazole molecules and two oxygen atoms of two carboxyl groups from different acid radicals. The Co–N distances are equal to 2.022(2) and 2.031(2) Å, while the Co–O distances are 1.972(2) and 2.000(2) Å. The carboxyl groups of the Pht2–radical and the aromatic nucleus form angles of 47.2° and 35.9°, whereas the angle formed by the carboxyl groups themselves is 50.3°. Compound Iis a polymer, which is confirmed by the 1,6-bridging function of the o-phthalic acid radical. The Co···Co distance in a chain is equal to 7.367 Å. Separate chains are united in the crystal into a framework via N–H···O hydrogen bonds.  相似文献   

18.
1 INTRODUCTION The insertion of unsaturated molecules into the lanthanide-ligand bond has attracted considerable attention, because it is a fundamental step for many metal-promoted transformations, in which some va- luable new methods for the formation of carbon- carbon and carbon-heteroatom bonds can be deve- loped and some complexes with novel structures or peculiar characters can be obtained[1~4]. Notably, in contrast to the wide reaction chemistry of organo- lanthanide alkyl (aryl), am…  相似文献   

19.
1 INTRODUCTIONMany complexes of 2-aminopyridine N-oxide (apo) have been characterized by infrared spectra, X-ray powder diffraction spectra, and by magnetic measurements and electronic spectra at liquid nitrogen temperature, but very few of them are their crystal X-ray studies[1~3]. Recently, a number of bridged binuclear copper (II) complexes have been reported, some of which have important potential applications in bioinorganic chemistry and materials[4~6]. Particularly, the complexes …  相似文献   

20.
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