Dimer of Bis[trans-5-methyl-2-[2-(4-methoxylphenyl) ethenyl]-benzoxazole]di-μ-nitratosilver(I)

The title complex [AgNO3(C17H15NO2)2]2 was synthesized and characterized by X-ray diffraction analysis. The compound crystallizes in triclinic, space group Pī with a = 11.226(7), b = 11.906(7), c = 12.144(7) (A。), α = 99.796(10), β = 91.631(10), γ = 101.225(10)°, V = 1565.6(16)(A。)3, Z = 1, Mr = 1400.96, Dc = 1.486 g/cm3, F(000) = 716 and μ(Mo-Kα) = 0.697 mm-1. The final R and wR are 0.0401 and 0.0995, respectively for 5492 independent observable reflections with I > 2σ(I). The results show that the central Ag atom is four-coordinated with two O atoms from two distinct NO3- anions and two N atoms from two trans-5-methyl-2-[2-(4-methoxylphenyl)ethenyl]- benzoxazole ligands, and the two Ag atoms bridged with two O atoms give an interesting Ag-O-Ag-O parallelogram structure. The coordination sphere of Ag atom exhibits a heavily distorted tetrahedral geometry and the coordination angles lie in the range of 66.73(12)～129.59(10)°. The intra- molecular dihedral angles between the benzoxazolyl and phenyl planes are 4.1(3) and 2.9(3)°, respectively.     

Crystal Structure and Characterization of Bis(4-isoniazidylthioformyl) Disulfide Hydration Sodium Coordination Polymer: n[(4-Pyridyl-CONHNCS2)22-]·[Na2(H2O)82+]n

The title compound has been prepared and characterized by elemental analysis, infrared spectra, NMR and thermal analyses, and its crystal structure was determined by X-ray diffraction method. The crystal crystallizes in the monoclinic system, space group C2/c with a = 2.3066(5), b = 0.53320(11), c = 2.3236(5) nm, β = 102.76(3)°, V = 2.7872(10) nm3, Mr = 612.67, Z = 4, Dc = 1.460 g/cm3, R = 0.0570 and wR = 0.1271. In the title compound, two 4-isoni- azidylthioformyl units are bridged by S-S bond (0.2037(3) nm). The Na ions are linked by O(4), O(4A), O(1) and O(1A) to form a one-dimensional hydration sodium coordination polymer. The Na ion is coordinated by a meridional arrangement of the six O atoms to assume a slightly distorted octahedron as a result of intermolecular hydrogen bonds. The thermal analytical data indicate that it decomposes completely at the temperature of 609.26 ℃.     

Synthesis and Crystal Structure of Bis[2-[2-(diethylamino)ethyliminomethyl]-4-nitrophenolato]dimethanolcobalt(II) Dinitrate

1 INTRODUCTION The significance of cobalt coordination com- pounds in biological systems is recognized[1～3]. In many instances the cobalt coordination compounds of Schiff bases have been suggested as models to describe energy transfer in naturally occurring systems. In such cases the coordination sphere about the metal ion is believed to play an important role in determining the nature of the model system[4, 5]. In order to investigate the structures of such complexes, we report herein t…     

CRYSTAL STRUCTURE OF [Et_4N]_2[Mo_2O_2(μ-S)_2(S_2)_2]

<正> [(C2H5)4N]2[Mo2o2S2(S2)2], Mr = 676. 74, monoclinic, P21/c, a = 13.510(2), b = 14.373(2), c=14. 777(3)(?), β = 97.53(2)°, V = 2844.7(9) (?)3, Z = 4, Dc= 1. 58g/cm3, μ(MoKα) = 13.0cm-1, F(000) = 1384, R =0. 033 for 1803 observed reflections. The structure contains discrete [Mo2O2S2(S2)2]2- anions and Et4N+ cations. The two oxygen atoms bonded to the Mo atoms are in cis-form with respect to the Mo2S2 bridging unit, with an average Mo- O distance of 1. 678 (?), The Mo…Mo distance is 2. 832(1)(?).     

Synthesis and Structure of Bis[2,6-bis(2-pyridylamino)pyridinium] Tetrachlorocadmiumate(II)

1 INTRODUTION The d10 configuration of Cd(II) permits a wide variety of coordination numbers and geometries[1~3]. In recent years, one-, two- and three-dimensional infinite supramolecular coordination assemblies of Cd(II) have been the subject of great interest owing to their potential applications in catalysis, optical properties, clathration, etc[4~8]. In fabricating the coordination assemblies, organic ligands as well as inorganic anions have been observed to control the structural di…     

Preparation and x-ray structure analysis of [Rh2Cl2(μ-CO)(μ-vdpp)2] [vdpp=H2C=C(PPh2)2]

Summary The complex [Rh₂Cl₂(-CO)(-vdpp)₂] (1) (vdpp=H₂C=C(PPh₂)₂) was prepared by reaction of [Rh₂(CO)₄-(-Cl)₂] with vdpp. When (1) is allowed to stand overnight under an atmosphere of CO without stirringtrans-[Rh₂Cl₂(CO)₂(-vdpp)₂] is formed as a red precipitate in low yields. On rapid addition of CO the tricarbonyl complex [Rh₂(CO)₂(-CO)(-Cl)(-vdpp)₂]-Cl is formed instead. The chemical behaviour of the vdpp-substituted complex (1) is very similar to that of the corresponding dppm-substituted complex [Rh₂(Cl₂-(-CO)(-dppm)₂] (dppm=H₂C(PPh₂)₂). this similarity also extends to the molecular structures of both compounds. Unit cell parameters of (1): space group Pben (Z=8),a=2344.7(5),b=1506.9(7),c=3021.6(9)pm. Rh-Rh 267.4(1) pm.     

Na2[ZnⅡ(ida)2]7H20和Na4[HgⅡ(nta)2]7H20的合成及结构测定

金属离子ZnⅠ和HgⅠ分别是生物体必需的微量元素和对人体有害的毒性金属.如何有效地摄取ZnⅠ和排除HgⅠ一直是化学家感兴趣的研究课题.而ZnⅠ和HgⅠ能与各种氨基酸形成配合物,由于它们处于同一族,电子结构都是dl0,故其配位结构只取决于金属离子半径的大小和配体的形状[1～3].     

Synthesis and Structure of Catena-[Bis(2-Methylimidazole)(μ-Phthalato)cobaltate(II)]

A new coordination compound [Co(Pht)(2-MeIm)₂] (I), where Pht^2–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 Pht^2–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.     

Synthesis and Crystal Structure of a Sodium Monosulfuron-ester (N-[2'-(4-Methyl)pyrimidinyl]-2-carbomethoxy Benzyl Sulfonylurea Sodium)

Monosulfuron-ester is a novel sulfonylurea herbicide with ultra-low dosage. Herein sodium monosulfuron-ester was synthesized and its crystal structure was determined by X-ray diffraction method. The title compound belongs to monoclinic, space group P21/c with a = 9.335(5), b = 20.632(12), c = 13.853(8) (A), β = 107.193(9)°, Mr = 487.46, Z = 4, Dc = 1.270 g/cm3, μ = 0.293 mm-1, F(000) = 1015, R = 0.0859 and wR = 0.2633. In the title compound, Na coordinates with N(1), O(1) and O(3) from one monosulfuron-ester molecule, N(4A) and O(5A) from the other monosulfuron-ester molecule and one oxygen atom from DMSO to give six coordination bonds.     

Bis{(μ-acetato)[μ-bis(salicylidene)-1,3-propanediaminato]zinc(II)}zinc(II)

In the title linear trinuclear compound, [Zn{Zn(CH₃COO)(C₁₇H₁₆N₂O₂)}₂], the central Zn²⁺ ion, which is located on an inversion centre, has a distorted octahedral coordination involving four bridging O atoms from two N,N′-bis­(salicyl­idene)-1,3-propane­diaminate ligands in the equatorial plane and one O atom from each bridging acetate group in the axial positions. The coordination around the terminal Zn²⁺ ion is irregular square pyramidal, with two O and two N atoms of the ligand in the basal plane and one O atom from an acetate group in the apical position. The acetate bridges linking the central and terminal Zn²⁺ ions are mutually trans. The Zn⃛Zn distance is 3.0520 (8) Å. The relationship of this structure to that of [Zn{Cu(CH₃COO)(C₁₇H₁₆N₂O₂)}₂] is discussed.     

Synthesis and Structure of Bis[bis(tert-butylcyclopentadienyl) Ytterbium Chloride]

1INTRODUCTIONLanthanocenechlorideisanimportantprecursorforpreparationofthecomplex-escontainingLn-CandLn-Hbonds.Allbinuclearbicyclopentadienyllanthanidechlorideswiththeunsubstitutedcyclopentadienylexceptthoseoftheearlylanthanideareavailable['3.Recently,theuseofstericallybulkyligandsorbridgedbicyclopenta-dienylhasgivenCp',LnClforearlylanthanides[2-6i.Usingt-butylcyclopentadienylasaligand,wedescribedthestructuresofcomplexes(Bu'C5H')2LnCl(THF).(Ln=Pr,Nd,n=2;Ln=Gd,Yb,n=1)t7iandtheunsol…     

Heterobimetallic Cyclosiloxanolate Sandwich Clusters: Na[η6-cyclo(PhSiO2)6]2[Fe(OR)]2Ni4(μ6-Cl) (R = H, Me)

The heterobimetallic cyclosiloxanolate sandwich clusters Na[⁶-cyclo (PhSiO₂)₆]₂[Fe(OR)]₂Ni₄(₆-Cl) (R = H, Me) (1) were prepared from Na₂[(PhSiO₂)₆]₂Na₄Ni₄(OH)₂ in the form of solvates. The new clusters 1 were characterized by spectra (UV-VIS, IR, ¹H-NMR), cyclic voltammetry. conductivity, magnetic susceptibility, and single-crystal X-ray diffraction.     

CRYSTAL STRUCTURE OF (Br(μ-Met)(μ-Gly)(H_2O)_4]_2[Er(μ-Net)_2(H_2O)_4]_2(ClO_4)_(12)

<正> [Er(u-Met)(u-Gly)(H2O)4]2[Er(u-Met)2(HaO)4]2(ClO4)12(NMet=CH3S-(CH2)2CH(NH2)COOH,Gly=NH2CH2COOH), Mr=3194, trilinic, space group P1, a = 12.375(6),b= 14.041(13), c=19.074(13)A,α=80.85(6),β=80.72(6).γ=62.82(6)° ,Z=1,V= 2896A3,Dc=1.83 g/cm3,R=0.091. The carboxyl groups of Met and Gly in the title complex are bonded to Er atoms as bidentate bridging ligands.There are two different cations located at crystallographic symmetry centers in one unit cell.     

Ditantalum dinitrogen complex: reaction of H2 molecule with "end-on-bridged" [Ta(IV)]2(μ-η(1):η(1)-N2) and Bis(μ-nitrido) [Ta(V)]2(μ-N)2 complexes

To elucidate (i) the physicochemical properties of the {(η(5)-C(5)Me(5))[Ta(IV)](i-Pr)C(Me)N(i-Pr)}(2)(μ-η(1):η(1)-N(2)), I, [Ta(IV)](2)(μ-η(1):η(1)-N(2)), and {(η(5)-C(5)Me(5))[Ta(V)](i-Pr)C(Me)N(i-Pr)}(2)(μ-N)(2), II, [Ta(V)](2)(μ-N)(2), complexes; (ii) the mechanism of the I → II isomerization; and (iii) the reaction mechanism of these complexes with an H(2) molecule, we launched density functional (B3LYP) studies of model systems 1, 2, and 3 where the C(5)Me(5) and (i-Pr)C(Me)N(i-Pr) ligands of I (or II) were replaced by C(5)H(5) and HC(NCH(3))(2), respectively. These calculations show that the lower-lying electronic states of 1, [Ta(IV)](2)(μ-η(1):η(1)-N(2)), are nearly degenerate open-shell singlet and triplet states with two unpaired electrons located on the Ta centers. This finding is in reasonable agreement with experiments [J. Am Chem. Soc. 2007, 129, 9284-9285] showing easy accessibility of paramagnetic and diamagnetic states of I. The ground electronic state of the bis(μ-nitrido) complex 2, [Ta(V)](2)(μ-N)(2), is a closed-shell singlet state in agreement with the experimentally reported diamagnetic feature of II. The 1-to-2 rearrangement is a multistep and highly exothermic process. It occurs with a maximum of 28.7 kcal/mol free energy barrier required for the (μ-η(1):η(1)-N(2)) → (μ-η(2):η(2)-N(2)) transformation step. Reaction of 1 with H(2) leading to the 1,4-addition product 3 proceeds with a maximum of 24.2 kcal/mol free energy barrier associated by the (μ-η(1):η(1)-N(2)) → (μ-η(2):η(1)-N(2)) isomerization step. The overall reaction 1 + H(2) → 3 is exothermic by 20.0 kcal/mol. Thus, the addition of H(2) to 1 is kinetically and thermodynamically feasible and proceeds via the rate-determining (μ-η(1):η(1)-N(2)) → (μ-η(2):η(1)-N(2)) isomerization step. The bis(μ-nitrido) complex 2, [Ta(V)](2)(μ-N)(2), does not react with H(2) because of the large energy barrier (49.5 kcal/mol) and high endothermicity of the reaction. This conclusion is also in excellent agreement with the experimental observation [J. Am Chem. Soc. 2007, 129, 9284-9285].     

Dimer of Bis[trans-5-methyl-2-[2-（4-methoxylphenyl） ethenyl]-benzoxazole]di-μ-nitratosilver（I）

1 INTRODUCTION We are presently involved in the synthesis and photodimerization of the analogues of trans-2-sty- rylbenzoxazole (BOEP), which have been widely reported as fluorescent whiteners and remedies[1]. Some structures of BOEP derivatives and thei…     

A New Short Synthesis of 3, 3′-Methylene Bis[Coumarins] and 3,3-Methylene Bis[2-Diethylaminoquinolines]

Hitherto unknown six symmetrically and unsymmetrically substituted methylene bis(coumarins) and two methylene bis(quinolines) are synthesised by using 1:2 complex of N, N, N', N'-tetraethyl glutaramide with POCl₃ and its condensation with substituted salicyl-aldehydes and o-formyl acetanilides.     

Alkylation of [Pt2(μ-S)2(PPh3)4] with boronic acid derivatives

The reactivity of the metalloligand [Pt₂(μ-S)₂(PPh₃)₄] with the boron-functionalized alkylating agents BrCH₂(C₆H₄)B(OR)₂ (R = H or C(CH₃)₂) was investigated by electrospray ionization mass spectrometry (ESI-MS) in real time using pressurized sample infusion (PSI). The macroscopic reaction of [Pt₂(μ-S)₂(PPh₃)₄] with one mole equivalent of alkylating agents BrCH₂(C₆H₄)B{OC(CH₃)₂}₂ and BrCH₂(C₆H₄)B(OH)₂ gave the dinuclear monocationic μ-sulfide thiolate complexes [Pt₂(μ-S){μ-SCH₂(C₆H₄)B{OC(CH₃)₂}₂}(PPh₃)₄]⁺ and [Pt₂(μ-S){μ-S⁺CH₂(C₆H₄)B(OH)(O^?)}(PPh₃)₄]. The products were isolated as the [PF₆]^? salt and zwitterion, respectively, and fully characterized by ESI-MS, IR, ¹H and ³¹P NMR spectroscopy, and single-crystal X-ray structure determinations.     

The preparation and structure of the tetranuclear ruthenium cluster [Ru4(CO)10(μ2-Cl)2(μ3-OEt)2]

The tetranuclear ruthenium cluster [Ru₄(CO)₁₀Cl₂(OEt)₂] has been prepared in low yield by the reaction of [Ru₃(CO)₁₂] with [N(PPh₃)₂]Cl in refluxing EtOH, followed by oxidation with either [NO][BF₄] or Ag[ClO₄]. A single-crystal X-ray analysis of the complex shows that the four metal atoms adopt a planar geometry with one ruthenium bonded by two μ₂-Cl ligands and two μ₃-OEt ligands to a trinuclear fragment. This complex crystallises in the monoclinic space group I2/c, with a 14.458(3), b 22.073(6), c 15.302(4) Å, β 99.54(2)°, Z = 8; 3113 observed data with F > 3σ(F) were refined by blocked full-matrix least squares to R = 0.031, R_w = 0.034.     

SYNTHESIS AND CRYSTAL STRUCTURE OF COMPLEX [CrMo_3 (μ_3-O)_3(μ-O)(μ-O_2CCH_3)_5(O_2CCH_3)_3]Na2 · H_2O

<正> The title complex C CrMo3 (μ3-O )3 (μ-O) (μ-O2CCH3 )5 (O2CCH3)3]2Na2 · H2O (Mr=1814. 32) crystallizes in monoclinic, space group P21/ n with a=11.209(5), b=18. 05(1), c=14. 44(1) A , β= 98. 30(5)°. V=2890 (3) A3, Z=2, A = 2. 08 g/cm3, F(000) -1780, Final R = 0. 049, Rw = 0. 058 for 2622 independent reflectons with I>3σ(I). The complex anion contains two Mo3O4 cores which connect two chromium atoms through four μ3-O atoms and eight bridging CH3COO- groups. Each of the Cr atoms and the Mo atoms is coordinated by six oxygen atoms. The anions are linked by Na cations to form one-dimensional infinite chain structure.