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1.
Three ternary rare earth [NdIII ( 1 ), SmIII ( 2 ) and YIII ( 3 )] complexes based on 3‐[(4,6‐dimethyl‐2‐pyrimidinyl)thio]‐propanoic acid (HL) and 1,10‐phenanthroline (Phen) were synthesized and characterized by IR and UV/Vis spectroscopy, TGA, and single‐crystal X‐ray diffraction. The crystal structures showed that complexes 1 – 3 contain dinuclear rare earth units bridged by four propionate groups and are of general formula [REL3(Phen)]2 · nH2O (for 1 and 2 : n = 2; for 3 : n = 0). All rare earth ions are nine‐coordinate with distorted mono‐capped square antiprismatic coordination polyhedra. Complex 1 crystallizes in the monoclinic system, space group P21/c with a = 16.241(7) Å, b = 16.095(7) Å, c = 19.169(6) Å, β = 121.48(2)°. Complex 2 crystallizes in the monoclinic system, space group P21/c with a = 16.187(5) Å, b = 16.045(4) Å, c = 19.001(4) Å, β = 120.956(18)°. Complex 3 crystallizes in the triclinic system, space group P1 with a = 11.390(6) Å, b = 13.636(6) Å, c = 15.958(7) Å, α = 72.310(17)°, β = 77.548(15)°, γ = 78.288(16)°. The antioxidant activity test shows that all complexes own higher antioxidant activity than free ligands.  相似文献   

2.
In the course of investigations relating to magnesia oxysulfate cement the basic magnesium salt hydrate 3Mg(OH)2 · MgSO4 · 8H2O (3–1–8 phase) was found as a metastable phase in the system Mg(OH)2‐MgSO4‐H2O at room temperature (the 5–1–2 phase is the stable phase) and was characterized by thermal analysis, Raman spectroscopy, and X‐ray powder diffraction. The complex crystal structure of the 3–1–8 phase was determined from high resolution laboratory X‐ray powder diffraction data [space group C2/c, Z = 4, a = 7.8956(1) Å, b = 9.8302(2) Å, c = 20.1769(2) Å, β = 96.2147(16)°, and V = 1556.84(4) Å3]. In the crystal structure of the 3–1–8 phase, parallel double chains of edge‐linked distorted Mg(OH2)2(OH)4 octahedra run along [–110] and [110] direction forming a pattern of crossed rods. Isolated SO4 tetrahedra and interstitial water molecules separate the stacks of parallel double chains.  相似文献   

3.
Two new metal‐organic coordination polymers[Eu(m‐BDC)1.5(MOPIP) · 1/2H2O]n ( 1 ) and [Co(m‐BDC)(MOPIP)2 · 2H2O]n ( 2 ) [m‐H2BDC = benzene‐1, 3‐dicarboxylic acid, MOPIP = 2‐(4‐methoxyphenyl)‐1H‐imidazo[4, 5‐f] 1 , 10 phenanthroline] were hydrothermally synthesized and structurally characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction. The coordination polymers crystallize in monoclinic space group P21/m for 1 ( 2 : P21/n), with a = 9.779(2), b = 18.242(4), c = 17.146(3) Å, β = 106.41(3)° for 1 , and with a = 8.2153(16), b = 27.974(6), c = 17.974(4) Å, β = 100.40(3)° for 2 . The crystal structure of complex 1 is a zipper‐like chain of octacoordinate Eu3+ ions, in which Eu3+ ions are bridged in two coordination modes by m‐BDC2+ ligands and decorated by MOPIP ligands. The molecular structure of complex 2 consists of a hexacoordinte Co2+ atom, which generates a slightly distorted octahedral arrangement, and assembles into three‐dimensional supramolecular nets by π ··· π stacking interactions. Additionally, these two compounds show strong fluorescence in the solid state at room temperature. Natural bond orbital (NBO) analysis is performed by using the NBO method built in Gaussian 03 Program. The calculation results show a weak covalent interaction between the coordinated atoms and metal ions.  相似文献   

4.
A new zinc phosphite with the formula Zn3(tren)(HPO3)3·xH2O (x≈0.5) has been synthesized under hydrothermal conditions and characterized by FTIR, elemental analysis, powder X‐ray diffraction, single‐crystal X‐ray diffraction, thermogravimetric analysis and its fluorescent spectrum. The compound crystallizes in the triclinic system, space group (No.2), a = 10.1188(9) Å, b = 10.4194(9) Å, c = 10.5176(9) Å, α = 60.763(2)°, β = 70.6150(10)°, γ = 80.725(2)°, V = 912.77(14) Å3, Z = 2. The structure consists of double crankshaft chains, which are linked by Zn‐O‐P bonds to form 8‐ and 12‐membered channels along the [100] direction. The claw‐like Zn‐centered complexes of Zn(N4C6H18) as the supported templates, hang into the 12‐MR channels through Zn‐O‐P linkages with framework.  相似文献   

5.
Four inorganic‐organic hybrid compounds with the formulae (1,10‐phen)(VO2)(IO3) ( 1 ), (2,2′‐bipy)(VO2)(IO3) ( 2 ), [Cu3(2,2′‐bipy)3Cl3(IO3)2]·I1.5 ( 3 ), and [Cu(2,2′‐bipy)(H2O)(IO3)2]· (H2O)2 ( 4 ) are hydrothermally synthesized at 120 °C for 6 d and characterized by single‐crystal X‐ray diffraction. The use of two different bidentate organodiamine ligands 1,10‐phen and 2,2′‐bipy in the V/I/O system gives rise to compounds 1 and 2 , which crystallize in a monoclinic system with the space group C2/c, a = 17.8131(6) Å, b = 15.0470(7) Å, c = 12.9902(4) Å, β = 133.095(2)°, V = 2542.49(17) Å3 for 1 and space group P21/c, a = 13.3095(5) Å, b = 15.0993(8) Å, c = 13.0454(4) Å, β = 116.971(2)°, V = 2335.88(17) Å3 for 2 . The use of the bidentate organodiamine ligand 2,2′‐bipy in the Cu/I/O system gives rise to the variety in the structure of products 3 and 4 , which crystallize in a triclinic system with the same space group . a = 8.5143(2) Å, b = 10.4908(3) Å, c = 22.8420(6) Å, α = 93.769(10)°, β = 91.723(10)°, γ = 112.111(10)°, V = 1882.83(9) Å3 for 3 and a = 6.731(6) Å, b = 10.110(4) Å, c = 12.899(6) Å, α = 106.00(5)°, β = 95.45(4)°, γ = 107.69(6)°, V = 788.4(9) Å3 for 4 . The solid‐state structures of the compounds 1 and 2 have chains with repeat units of alternative corner sharing of [VO4N2] octahedra and [IO3] pyramids. Compound 3 is a chain containing [IO3] pyramids and [VO4N] square pyramids and compound 4 consists of Cu(2,2′‐bipy)2+ linked by one water molecule and two [IO3] pyramids. The thermal stabilities of the compounds are investigated.  相似文献   

6.
Three polymorphs of barium dihydrogen‐hypodiphosphate(IV)‐dihydrate, BaH2P2O6 · 2H2O ( A , B and C ), were obtained and structurally characterized by single‐crystal X‐ray diffraction. A crystallizes in the monoclinic space group P21/n (no. 14) with a = 7.459(1) Å, b = 8.066(1) Å, c = 12.460(2) Å, β = 91.27(1) ° and Z = 4. B crystallizes in the monoclinic space group C2/c (no. 15) with a = 11.049(8) Å, b = 6.486(3) Å, c = 10.956(6) Å, β = 106.89(5) ° and Z = 4. C crystallizes in the orthorhombic space group C2221 (no. 20) with a = 9.193(3) Å, b = 6.199(2) Å, c = 12.888(4) Å and Z = 4. Discrete [H2P2O6]2– units, barium cations and water molecules, held together by intermolecular hydrogen bonds of the type O–H ··· O, build up the structures of the three polymorphs. The phase purity of A and C was verified by powder diffraction measurements.  相似文献   

7.
The reaction of acetylferrocene [Fe(η‐C5H5)(η‐C5H4COCH3)] (1) with (2‐isopropyl‐5‐methylphenoxy) acetic acid hydrazide [CH3C6H3CH(CH3)2OCH2CONHNH2] (2) in refluxing ethanol gives the stable light‐orange–brown Schiff base 1‐[(2‐isopropyl‐5‐methylphenoxy)hydrazono] ethyl ferrocene, [CH3C6H3CH(CH3)2OCH2CONHN?C(CH3)Fe(η‐C5H5)(η‐C5H4)] (3). Complex 3 has been characterized by elemental analysis, IR, 1H NMR and single crystal X‐ray diffraction study. It crystallizes in the monoclinic space group P21/n, with a = 9.6965(15), b = 7.4991(12), c = 29.698(7) Å, β = 99.010(13) °, V = 2132.8(7) Å3, Dcalc = 1.346 Mg m?3; absorption coefficient, 0.729 mm?1. The crystal structure clearly shows the characteristic [N? H···O] hydrogen bonding between the two adjacent molecules of 3. This acts as a bidentale ligand, which, on treatment with [Ru(CO)2Cl2] n, gives a stable bimetallic yellow–orange complex (4). Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

8.
Two polymorphs of a zero‐dimensional (molecular) zinc phosphate with the formula [Zn(2,2′‐bipy)(H2PO4)2]2 have been synthesized by a mild hydrothermal route and their crystal structures were determined by single crystal X‐ray diffraction (triclinic, space group (No. 2), Z = 2, α‐form: a = 8.664(1), b = 8.849(2), c = 10.113(2) Å, α = 97.37(2)°, β = 100.54(2)°, γ = 100.98(2)°, V = 737.5(3) Å3; β‐form: a = 7.5446(15), b = 10.450(2), c = 10.750(2) Å, α = 67.32(3)°, β = 81.67(3)°, γ = 69.29(3)°, V = 731.4(3) Å3). Both structures consist of distorted trigonal‐bipyramidal ZnO3N2 units condensed with PO2(OH)2 tetrahedra through common vertices giving rise to dimers [Zn(2,2′‐bipy)(H2PO4)2]2. The structures are stabilized by extensive inter‐ and intramolecular hydrogen bond interactions. Both modifications display subtle differences in their packing originating from the hydrogen bond interactions as well as π…π interactions between the organic ligands.  相似文献   

9.
The zinc(II) coordination polymers [Zn(Htatb)(2,2′‐bipy) · (NMP) · H2O] ( 1 ) and [Zn3(tatb)2(2,2′‐bipy)3 · H2O] ( 2 ) (H3tatb = 4,4′,4′′‐s‐triazine‐2,4,6‐triyl‐tribenzoic acid; 2,2′‐bipy = 2,2′‐bipyridyl, NMP = N‐methyl‐2‐pyrrolidon), were synthesized hydrothermally, and characterized by infrared spectroscopy (IR), powder X‐ray diffraction (PXRD), and single‐crystal X‐ray diffraction. Both compounds 1 and 2 possess expectant low dimensional coordination structures, which further connected into interesting 3D networks by hydrogen bond and strong π–π interactions. Moreover, the thermal stabilities and fluorescent properties of 1 and 2 were investigated.  相似文献   

10.
Reaction of the ligands 2‐phenyl‐1H‐1,3,7,8‐tetraazacyclopenta[l]phenanthrene (PTCP) and benzene‐1,3‐dicarboxylic acid (m‐H2BDC) with Ln2O3 under hydrothermal conditions lead to three isomorphous coordination polymers [Ln2(PTCP)2(m‐BDC)3·H2O]n (Ln = Tm, 1 ; Nd, 2 ; Ce, 3 ). The coordination polymers crystallize in monoclinic, space group P21/m with a = 9.8340(2), b = 17.9140(4), c = 15.6050(3) Å, β = 100.51(3)° for 1 , with a = 9.8423(3), b = 18.3562(4), c = 15.6209(3) Å, β = 102.138(3)° for 2 , and with a = 9.8620(2), b = 18.4960(4), c = 15.6530(3) Å, β = 102.42(3)° for 3 , respectively. The metal ions (Ln3+) are located in an octacoordinated environment and the dinuclear [Ln2O12N4] units act as octahedral secondary building units (SBU), which are bridged in two coordination modes by six m‐BDC ligands to form a three‐strand‐like chain. These chains are decorated by PTCP ligands and form unique three zipper‐like structures, which are further assembled into three‐dimensional supramolecular nets by π ··· π stacking interactions. Additionally, hydrogen bonds are observed in the structures. Furthermore, compounds 1 – 3 were studied by IR spectrocopy and thermogravimetric analyses.  相似文献   

11.
The hydrothermal reaction of Cd(NO3) · 4H2O with 4,4′‐bipyridine (bipy) and 3‐carboxyphenoxyacetatic acid (3‐H2CPOA) afforded a 3D metal‐organic framework (MOF) [Cd(3‐CPOA)(bipy)]n · 3.5nH2O, which was characterized by elemental analyses, IR spectroscopy, thermogravimetric analyses, and X‐ray diffraction. The single‐crystal structural analysis revealed that it has a Cds‐type topological network with 1D channels that contain encapsulated water molecular tapes.  相似文献   

12.
通过水热合成技术,一个新颖的基于Zn配合物修饰的Keggin型钴钨酸的有机-无机杂化化合物:[Zn(2,2’-bipy)3]3{[Zn(2,2’-bipy)2(H2O)]2 [HCoW12O40] 2 }.H2O已经被合成,化合物通过红外光谱、热重分析和单晶X-射线衍射进行了表征。单晶X-射线衍射的结果显示标题化合物是由一个单支撑的{[Zn(2,2’-bipy)2(H2O)]2 [HCoW12O40] 2}6-多阴离子,三个[Zn(2,2’-bipy)3]2+阳离子和一个水分子构成。有趣的是[Zn(1)(2,2’-bipy)3]2+阳离子通过氢键连接在一起形成螺旋链。另外标题化合物在空气中是稳定的,并且在室温下显示了强的荧光。  相似文献   

13.
Crystals of anionic Na[CuCl2(HOCH2C≡CCH2OH)]·2H2O π‐complex have been synthesized by interaction of 2‐butyne‐1,4‐diol with CuCl in a concentrated aqueous NaCl solution and characterized by X‐ray diffraction at 100 K. The crystals are triclinic: space group , a = 7.142(3), b = 7.703(3), c = 10.425(4) Å, α = 105.60(3), β = 99.49(3), γ = 110.43(3)°, V = 495.9(4) Å3, Z = 2, R = 0.0203 for 3496 reflections. The structure is built of discrete [CuCl2(HOCH2C≡CCH2OH)]? anionic stacks and polymeric cations among the stacks. The CuI atom adopts trigonal planar coordination of two Cl? anions and the C≡C bond of 2‐butyne‐1,4‐diol, Cu–(C≡C) distance is equal to 1.903(3) Å. Na+ cations environment is octahedral and consists of O and Cl atoms. The crystal packing is governed by strong hydrogen bonds of O–H···Cl and O–H···O types.  相似文献   

14.
The ligand N,N‐dimethyl(N′‐trimethylsilyl)ethane‐1,2‐diamine (HL) was treated with ZnEt2 in varying stoichiometric ratios to synthesize [EtZnL]2 and [ZnL2] complexes. Crystal data: [EtZnL]2, monoclinic, P21/n, a = 10.0149(5) Å, b = 8.0296(3) Å, c = 16.1689(8) Å, β = 91.715(2)°. [ZnL2], monoclinic, P21/n, a = 8.8457(3) Å, b = 15.4249(6) Å, c = 16.0121(7) Å, β = 92.656(1)°. The former complex is an amido nitrogen bridged dimer with distorted tetrahedral stereochemistry of the zinc atom and the latter is a distorted tetrahedral monomer based on amide/amine chelation.  相似文献   

15.
岳琦  杨进  袁宏明  陈接胜 《中国化学》2006,24(8):1045-1049
A two-coordinate copper(Ⅰ) complex, Cu2(bipy)(H2L)2 (1) (H3L=cyanuric acid, bipy=4,4'-bipyridyl), which exhibits strong photoluminescence, has been synthesized under hydrothermal conditions and structurally characterized by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/n, with cell parameters: Mr= 539.42, a= 13.4806(5)A↑°, b=4.5234(2) A↑°, c= 15.4952(8)A↑°,β = 105.526(3)°, V=910.39(7)A↑°^3, Z=2 and μ=3.52 mm^ -1. In the structure the two Cu(Ⅰ) ions are bridged by bipy to form a two-coordinate copper(Ⅰ) dimer. The adjacent dimer units are connected by hydrogen bonding interactions, resulting in 1D zigzag chains along the c axis. 1 emits intense yellow light when excited with UV light.  相似文献   

16.
Hydrated alkaline earth metal salts of 5‐amino‐1H‐tetrazole ( B ) were synthesized by reaction of B with a suitable metal hydroxide in water. All compounds were fully characterized by analytical (elemental analysis and mass spectrometry) and spectroscopic (IR, Raman, 1H and 13C NMR) methods. Additionally, the crystal structures of the magnesium [ 1· 4H2O: triclinic, P$\bar {1}$ , a = 5.940(1) Å, b = 7.326(1) Å,c = 7.383(1) Å, α = 106.10(1)°, β = 106.51(1)°, γ = 111.85(1)°, V = 258.0(1) Å3], calcium [ 2· 6H2O: monoclinic, P21/m, a = 6.904(1) Å,b = 6.828(1) Å, c = 10.952(2) Å, β = 94.50(2)°, V = 514.6(1) Å3], and strontium [ 3· 6H2O: orthorhombic, Cmcm, a = 6.987(1) Å, b = 28.394(2) Å, c = 7.007(1) Å, V = 1390.3(2) Å3] were determined by low temperature X‐ray diffraction. Additionally, the (gas phase) structure of the 5‐amino‐1H‐tetrazole anion ([ B ]) was also studied by natural bond orbital (NBO) analysis [B3LYP/6‐31+G(d,p)]. Lastly, standard tests were used to determine the sensitivity towards impact, friction, and electrostatic discharge of the compounds and the thermal stability was assessed by differential scanning calorimetry (DSC) analysis.  相似文献   

17.
The complexes of 2,11‐dithia‐4,5,6,7,8,9‐hexahydro[3.3]paracyclophane (dthhpcp) with Cu(I), i.e. [Cu2I2(dthhpcp)2]·2H2O 1 , or with Ag(I), i.e. [Ag(dthhpcp)(NO3)]thf 2 and [Ag(dthpcp)(CF3COO)] 3 , were prepared for structural study by single‐crystal X‐ray diffraction analysis. For these three complexes, dthhpcp serves as a bridging group in the polymeric structure through bridging sulfur atoms via metal, while the bonding of anion with the second metal atom forms the multi‐diminished structures. Complex 1 is a novel two‐dimensional coordination polymer composed of Cu6 motifs, in which Cu2I2 formed a square planar unit to link the dthhpcp molecule. The two oxygen atoms of the nitrate anion as a bridge for two Ag atoms in complex 2 provides a three‐dimensional channel framework of silver(I) with a tetrahydrofuran molecule as a guest inside the open cavities. In contrast, the analogous reaction with silver triflouroacetate gave a complex 3 , which is composed of infinite linear chains of‐Ag‐dthhpcp‐Ag‐dthhpcp‐ along the a axis. Unit cell data: complex 1 , orthorhombic system, space group P2(1)2(1)2(1), a = 19.2982(11) Å b = 16.5661(10) Å, c = 25.3006(15) Å, β = 90°, Z = 8; complex 2 , orthorhombic system, space group Pna2(1), a = 8.8595(6) Å, b = 12.6901(9) Å, c = 19.8449(14) Å, β = 90°, Z = 4; complex 3 , monoclinic system, space group P2(1)/n, a = 8.845(3) Å, b = 20.841(6) Å, c = 11.061(3) Å, β = 107.832(6)°, Z = 4.  相似文献   

18.
The η2‐thio‐indium complexes [In(η2‐thio)3] (thio = S2CNC5H10, 2 ; SNC4H4, (pyridine‐2‐thionate, pyS, 3 ) and [In(η2‐pyS)22‐acac)], 4 , (acac: acetylacetonate) are prepared by reacting the tris(η2‐acac)indium complex [In(η2‐acac)3], 1 with HS2CNC5H10, pySH, and pySH with ratios of 1:3, 1:3, and 1:2 in dichloromethane at room temperature, respectively. All of these complexes are identified by spectroscopic methods and complexes 2 and 3 are determined by single‐crystal X‐ray diffraction. Crystal data for 2 : space group, C2/c with a = 13.5489(8) Å, b = 12.1821(7) Å, c = 16.0893(10) Å, β = 101.654(1)°, V = 2600.9(3) Å3, and Z = 4. The structure was refined to R = 0.033 and Rw = 0.086; Crystal data for 3 : space group, P21 with a = 8.8064 (6) Å, b = 11.7047 (8) Å, c = 9.4046 (7) Å, β = 114.78 (1)°, V = 880.13(11) Å3, and Z = 2. The structure was refined to R = 0.030 and Rw = 0.061. The geometry around the metal atom of the two complexes is a trigonal prismatic coordination. The piperidinyldithiocarbamate and pyridine‐2‐thionate ligands, respectively, coordinate to the indium metal center through the two sulfur atoms and one sulfur and one nitrogen atoms, respectively. The short C‐N bond length in the range of 1.322(4)–1.381(6) Å in 2 and C‐S bond length in the range of 1.715(2)–1.753(6) Å in 2 and 3 , respectively, indicate considerable partial double bond character.  相似文献   

19.
The ternary Cu(II) complex with 2,2′‐bipyridyl (bipy) and L‐methioninate (L‐Met) has been synthesized and characterized by elemental analysis, molar conductivity, UV‐Vis spectra, IR spectra and pH‐potentiometric titration methods. The structure of the complex [Cu(L‐Met) (bipy) (H2O)]ClO4 · 3/8H2O was characterized by the X‐ray diffraction analysis. It crystallizes in the triclinic system, space group P1 with four molecules in a unit cell of dimensions, a = 0.7656(2) nm, b = 1.3142(3) nm, c = 2.0596(4) nm, α = 97.70(3)°, β = 97.96(3)°, γ = 94.33(3)°, V= 2.0244(8) nm3, R1, = 0.0441 and wR2 = 0.0678. The crystal contains four crystllographically independent [Cu(L‐Met) (bipy) (H2O)]+ complexes (Cu1—Cu4), having a distorted square‐pyramidal geometry with the same coordinated atoms around each copper center. The base plane is occupied by two nitrogen atoms of one bipy, the amino nitrogen atom and one carboxylate oxygen atom from each independent L‐Met moiety, and one water oxygen at an axial position. Cu1 and Cu3 are essentially enantiomers of Cu2 and Cu4. The four molecules are packed with each other by intermolecular hydrogen‐bonding and aromatic‐ring stacking interactions.  相似文献   

20.
Molecules of 2‐(2‐nitrophenylaminocarbonyl)benzoic acid, C14H10N2O5, are linked into centrosymmetric R(8) dimers by a single O—H⋯O hydrogen bond [H⋯O = 1.78 Å, O⋯O = 2.623 (2) Å and O—H⋯O = 178°] and these dimers are linked into sheets by a single aromatic π–π stacking interaction. The isomeric compound 2‐(4‐nitrophenylaminocarbonyl)benzoic acid crystallizes in two polymorphic forms. In the orthorhombic form (space group P212121 with Z′ = 1, crystallized from ethanol), the mol­ecules are linked into sheets of R(22) rings by a combination of one N—H⋯O hydrogen bond [H⋯O = 1.96 Å, N⋯O = 2.833 (3) Å and N—H⋯O = 171°] and one O—H⋯O hydrogen bond [H⋯O = 1.78 Å, O⋯O = 2.614 (3) Å and O—H⋯O = 173°]. In the monoclinic form (space group P21/n with Z′ = 2, crystallized from acetone), the mol­ecules are linked by a combination of two N—H⋯O hydrogen bonds [H⋯O = 2.09 and 2.16 Å, N⋯O = 2.873 (4) and 2.902 (3) Å, and N—H⋯O = 147 and 141°] and two O—H⋯O hydrogen bonds [H⋯O = 1.84 and 1.83 Å, O⋯O = 2.664 (3) and 2.666 (3) Å, and O—H⋯O = 166 and 174°] into sheets of some complexity. These sheets are linked into a three‐dimensional framework by a single C—H⋯O hydrogen bond [H⋯O = 2.45 Å, C⋯O = 3.355 (4) Å and C—­H⋯O = 160°].  相似文献   

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