SYNTHESIS AND CRYSTAL STRUCTURE OF OXAMIDATO-BRIDGED BINUCLEAR COPPER(II) COMPLEXES

Abstract

The compounds [Cu(oxpn)] (1), [(bpy)(H₂O)Cu(μ-cis-oxpn)Cu(H₂O)] · 2NO₃ · 2H₂O (2) and [(Him)(NO₃)Cu(μ-trans-oxpn)Cu(Him)(NO₃)] (3), where oxpn is the dianion of N,N′-bis(3-aminopropyl)oxamide, bpy is bipyridine and Him is imidazole, were prepared and characterized by elemental analysis and IR spectra. Complex (2) was also studied by thermochemical analysis and its structure determined by X-ray crystallography. The structure of complex (2) consists of binuclear copper(II) molecules in which the copper(II) atoms are bridged by an oxamidato group in the cis conformation resulting a copper-copper distance of 5.21 Å. Both copper(II) ions are in square-pyramidal surroundings with almost coplanar basal planes and a water molecule occupying the apical positions. The N atoms of the oxamidato moiety are trigonal. Two lattice water molecules together with the two coordinated ones hydrogen bond with nitrate ions.     

SYNTHESIS,CHARACTERIZATION, AND REPRESENTATIVE CRYSTAL STRUCTURE OF LIPOPHILIC PLATINUMII (HOMOPIPERAZINE)CARBOXYLATE COMPLEXES

Abstract

A series of new lipophilic platinum(II) complexes of the type [Pt(HPIP)L₂] and [Pt(HPIP)L] (where HPIP = homopiperazine; L = acetate, propionate, butyrate, pentanoate, hexanoate, heptanoate, octanoate, nonanoate, decanoate, undecanoate, laureate, tridecanoate, myristate, pentadecanoate, palmitate, or heptadecanoate; and LL = oxalate, or tartronate) were synthesized and characterized by elemental analysis, IR, ¹³CNMR, and ¹⁹⁵Pt NMR. In addition, the crystal structure of a representative complex [Pt^II(HPIP)(pentadecanoate)₂], was determined by X-ray diffraction. The crystals were monoclinic, space group P2₁/c, with a = 28.212(6)Å, b = 3.661(3)Å, c = 10.218(2)Å, and Z = 4. A total of 3940 reflections were collected, and the structure refined to R1 = 0.0522 and wR2 = 0.1333. The slightly distorted square plane of the platinum included the amino groups of the HPIP molecule in cis positions and oxygens from two monodentate pentadecanoates. The HPIP molecule was in a boat conformation and formed five- and six-member chelating rings with platinum. Together, these molecules formed an intricate network of intermolecular hydrogen bonds that held the crystal lattices together.     

DIRECT SYNTHESIS AND CRYSTAL STRUCTURE OF DIIODOETHYLENDIAMINELEAD(II) DIMETHYLSULFOXIDE

Abstract

A direct method of obtaining PbEnI₂.DMSO is reported. The crystal structure of the compound was determined by X-ray techniques. PbEnI₂.DMSO is triclinic, space group P 1, C₄H₁₄I₂N₂PbS, a=10.225(3), b=10.132(3), c=6.900(2) Å; α=90.83(2), β=88.30(2), γ=106.35(4)°; V=685.6(4) ų; z=2, calculated density 2.92 gcm^?3. Neutral PbEnI₂ complexes are associated with DMSO molecules via H-bonds. The lead(II) ion is covalently linked with a chelated En molecule (Pb-N 2.46–2.48 Å) and I^? anions (Pb-I 3.087–3.343 Å). Covalently bonded atoms form an umbrella-like coordination Pb(II) polyhedron. The side containing the lone electron pair of the lead(II) ion has coordination completed by two I^? anions of neighbouring molecules with the Pb-I 3.621–3.627 Å.     

SYNTHESIS AND X-RAY CRYSTAL STRUCTURE OF BIS (2-AMINOMETHYLAZIRIDINE)NICKEL(II) PERCHLORATE

Abstract

The structure of the big (2-aminomethylaziridine = azida)nickel(II) complex was determined by X-ray diffraction methods. The compound, [Ni(azida)₂](C1O₄)2, crystallizes in the triclinic space group P1, Z=l, with a = 7.3545(4), b = 8.5235(5), c = 6.2156(4)Å, α= 101.871(6). β = 103.217(6), γ= 111.283(4)°, and V= 335.07(5) ų. The crystal shows discrete centrosymmetncal [Ni(azida)]²⁺ units in which azida acts as bidentate chelating ligand through N aziridine and N amino atoms. Thus, Ni has a four-coordinate square-planar geometry with four nitrogens of azida. The aziridine ring is almost perpendicular to the coordination plane. The dihedral angle between the aziridine plane and the coordination plane is 75.28°.     

SYNTHESIS AND CRYSTAL STRUCTURE OF A MANGANESE(II) COMPLEX,Mn(phen)2(phcoo)2 2HzO

Abstract

The title complex has been prepared by the reaction of Mn(phcoo)2 with phen in EtOH/H₂O solution (where phcoo = the anion of benzoic acid, phen= 1,10-phenanthroline). The crystal structure has been determined by X-ray diffraction. The complex molecule has distorted octahedron geometry. Carboxyl O atoms coordinate to Mn(II) from unidentate ligands with a cis-configuration. Two uncoordinated O atoms of benzoate anions locate on the one side of the coordination plane so that there is free space on the other side of the plane; such a spatial arrangement may promote the attack of a water molecule at the manganese atom in the oxygen evolution process in photosystem II.     

CRYSTAL STRUCTURE AND THERMAL ANALYSIS OF A 4,4′-BIPY-BRIDGED BINUCLEAR ZINC(II) COMPLEX, 2[R2NCS2]2 · Zn(4,4′-BIPY) (R=PIPERIDYL)

Abstract

The crystal structure of the title complex 2[R₂NCS₂]₂ · Zn(4,4′-bipy) (R = Piperidyl), 1, revealed that it consists of dimers made up from two crystallographically independent molecules. Each zinc atom in 1 forms a 5-coordinate pseudo-square-based pyramidal arrangement (with four Zn-S and one Zn-N interactions). Bondlengths to Zn with the coordinating atoms are comparable to those in other Zn(II) dithiocarbamate complexes. The piperidine ring has a chair conformation. To allow improved packing, the title complex molecules form an approximately linear arrangement extending along both a and b. TGA showed that 1 is decomposed in two close steps to produce ZnS as identified by residual weight. The complex 1 crystallizes in the monoclinic space group C2/c with cell parameters: a = 22.021(5), b = 22.215(3), c = 17.537(2) Å, β = 93.49(2)°, V = 8563(3) ų and Z = 8. The structure was refined by full-matrix least-squares methods to R = 0.067, R_w = 0.114.     

SYNTHESIS AND CRYSTAL STRUCTURE OF NICKEL COMPLEX WITH TRIS(3-AMINOPROPYL)AMINE

Abstract

The crystal structure of [Ni(trpn)(NCS)₂] (trpn = tris(3-aminopropyl)amine) has been determined, in which the nickel(II) complex is octahedral. The complex forms a three-dimensional network through weak intermolecular hydrogen bonds S_NCS … H-N_amine and S … S contacts.     

磷酸三甲酯三（磷酸二甲酯）合镧的合成与结构研究

(RO)_2PO_2H型酸性磷酸醋由于含有多个可与金属配位的氧原子,可以和金属离子形成多种形式且结构特殊的配合物。作为一类重要的萃取剂,对酸性磷酸酯配合物的研究有助于了解萃取的规律和机理。虽然这类配合物的合成及结构已有报道,但最基本的磷酸二甲酯与金属离子配合物的结构未见报道。本工作首次合成了标题化合物,测定了它的红外光谱和单晶结构。现将结果简报如下。     

CRYSTAL STRUCTURE AND MORPHOLOGY OF NASCENT SAMPLES OF SYMMETRIC AROMATIC POLYESTERS I.POLY(P-PHENYLENE TEREPHTHALATE)

The morphology and crystal structure of poly(p-phenylene terephthalate) (PPT), prepared by confined thin film melt (CTFMP) and solution (CTFSP) and bulk solution polymerization, were characterized by transmission electron microscopy, electron diffraction and molecular modeling. The unit cell is monoclinic (P21/a space group) with parameters a =7.89, b = 5.49, c =12.65 A α= γ= 90°,β= 100.33°, density = 1.48 g/cm3, the a, b andβ values differing slightly from those reported previously in the literature. A degree of variation in relative intensities of hk0 reflections in, apparently, untilted [001] ED patterns was observed from a given sample, suggesting some variation in molecular packing. ED evidence was found for a second phase, with [001] appearing the same as for phase Ⅱ of the related poly(p-oxybenzoate) (PpOBA)polymer. CTFMP crystals polymerized above 220°C (up to 370°C) and CTFSP crystals polymerized at 300°C consisted of lamellae 100-200 A thick.     

THE CRYSTAL STRUCTURE OF DIBROMO (PHENYL-2-PYRIDYL DIMETHYLHYDRAZONE)PALLADIUM(II)

Abstract

Nitrogen-containing heterocyclic compounds play an important role in several biological processes. Furthermore, their biological activity seems often to depend upon interaction with a metal ion. Interest in the study of hydrazones and their metal complexes has been growing because of their physiological activity, coordination capability and application in analytical chemistry.^1,2 Many hydrazones and their metallic derivatives show very interesting biological activity, e.g., as antitumour or anticonvulsant agents, and behave as cytotoxic compounds toward tumour cells.³ During the past few years, in addition to platinum compounds, coordination compounds of palladium(II) and (IV) seem to be promising in cancer chemotherapy.⁴ Due to the biological activity of heterocyclic hydrazones and in continuing our systematic investigations of the platinum group metals with hydrazones and generally with heterocyclic nitrogen donor ligands,^5–10 we report here the crystal structure of dibromo(phenyl-2-pyridyldimethylhydrazone) palladium(II).     

STRUCTURE OF A POLYMERIC BENZENETETRACARBOXYLATO COMPLEX OF Mn(II) WITH IMIDAZOLE

Abstract

A novel polymeric μ-BTC complex of Mn(II) with imidazole has been synthesized, where BTC is the 1,2,4,5-benzenetetracarboxylato tetravalent anion, and its crystal structure has been determined by X-ray diffraction methods. The complex crystallizes in the monoclinic spacegroup P2₁/n with a = 11.184(5), b = 9.177(2), c = 18.243(1)Å and β = 107.84(1)°. Each BTC ligand, located around the crystallographic inversion centre, bridges four Mn(II) atoms through four carboxyl groups to form a three dimensional polymeric structure. The carboxyl groups in the ortho-position of BTC bridges Mn(II) atoms related by the crystallographic screw axis to form helical complex chains along the b axis. Coordination around the Mn(II) atom is distorted octahedral; two BTC anions coordinate to Mn(II), one in unidentate fashion and the other as a chelate. The coordination distance of the unidentate ligand is much shorter than in the chelated ligand.     

SYNTHESIS,CRYSTAL STRUCTURE AND NONLINEAR OPTICAL PROPERTIES OF THIOSEMICARBAZONE ZINC COMPLEX

Abstract

A new zinc bromide complex of a Schiff-base ligand derived from thiosemicarbazide and 4-methoxylphenyldehyde, which shows ca 13 times better SHG efficiency than urea, has been prepared and characterized. Single crystal X-ray diffraction analysis established that the coordination geometry about the zinc atom is tetrahedral with two equivalent Zn-Br and Zn-S bonds. The Schiff-base ligand is coordinated to the Zn(II) via the monodentate mercapto sulfur atom. The polar structure (space group Aba2) is stabilized by hydrogen bonds between the oxygen atom and the amino nitrogen atoms N(l).

The complex crystallizes in the orthorhombic space group Aba2 with cell parameters a=11.970(2), b = 21.888(2), c= 9.157(2)Å and Z = 4. The structure was solved by direct methods and refined by full-matrix least-squares to R = 0.065 and R _w = 0.117 for the 722 observed reflections with I > 2[sgrave](I).     

SYNTHESIS AND STRUCTURE OF Pd(II) COMPLEXES OF 1,2,3-TRIPHENYLGUANIDINE

Abstract

The formation of two complexes by reaction of [PdCl₄]^2- with 1,2,3-triphenylguanidine (PhNH)₂C=NPh under different metal/ligand ratios has been observed and the structure of the complex [(1,2,3-triphenylguanidine)₂PdCl₂] has been determined by X-ray diffraction methods. The ligands are coordinated as neutral monodentate molecules to the metal centre through their imine nitrogen atoms. The second Pd(II) complex is [Pd(1,2,3-triphenylguanidine)₄]²⁺ and was isolated by precipitation with ClO^? ₄.     

SYNTHESIS AND STRUCTURE OF A POLYMERIC 1,3-BENZENEDICARBOXYLATO COMPLEX OF Mn(II) WITH PHENANTHROLINE

Abstract

A novel Mn(II) complex bridged by 1,3-benzenedicarboxylate (BDC) has been synthesized by the diffusion method. The complex crystallizes in space group P2₁/c with a = 8.345(2), b = 10.427(1), c = 18.756(2) Å, β = 100.19(1)°. Each BDC bridges three Mn(II) atoms through two carboxyl groups with different coordination modes to form a complex polymeric chain. The coordination geometry around the Mn(II) atom is seriously distorted from the normal octahedron. Large deviations of the donor atoms out of the coordination planes and unexpected bond angles around Mn(II) and donor O atoms suggest the existence of an electrostatic interaction between Mn(II) and donor atoms in the complex. Close stacking of aromatic rings is observed in the complex, the distance between the neighboring phen planes being 3.2085 Å.     

SYNTHESIS AND STRUCTURES OF DICHLOROTETRAKIS-(PHENYLTHIOUREA) CADMIUM(II) AND CATENA-BIS(THIOCYANATE) BIS(PHENYLTHIOUREA)CADMIUM(II)

Abstract

Two new cadmium(II) complexes with phenylthiourea (PTU), namely Cd(PTU)₄Cl₂ (1) and [Cd₂(NCS)₂(μ₂-SCN)₂(PTU)₂(μ₂-PTU)₂] _n (2), have been prepared and characterized structurally by X-ray diffaction. Complex 1 crystallizes in the monoclinic space group C2/c, with a = 27.057(13), b = 8.108(3), c = 16.751(8) Å, β = 114.46°, V = 3345(3) ų, Z = 4. Complex 2 crystallizes in the triclinic space group P-1, with a = 9.336(3), b = 14.686(5), c = 16.911(5) Å, α = 71.36(2), β = 84.31(2), γ = 72.470(10)°, V = 2095.0(12) ų Z = 4. The structural analysis shows that each metal atom in both the mononuclear complex 1 and polynuclear complex 2 is octahedrally coordinated by four sulfur atoms and two chloro ligands or two nitrogen atoms from the thiocyanate groups, respectively. The PTU ligand can serve as either a monodentate ligand or a μ₂-bridging ligand upon coordination to a metal atom.     

三(2-苯并咪唑亚甲基)胺合锰的结构和量化计算

合成了三 ( 2 苯并咪唑亚甲基 )胺合锰 (II) (C48H5 0 N1 4 O4Mn2 Cl4) ,采用X射线单晶衍射方法测定了晶体结构 ,并进行了量子化学计算 .晶体属于单斜晶系 ,空间群P2 1 /C ,晶胞参数 :a =1 4 2 38( 7)nm ,b =2 4 80 2 ( 3)nm ,c =1 6 977( 7)nm ,β =92 51( 4)° ,V =5 9893nm3 ,Z =4 用重原子法及傅里叶合成方法解出结构 ,最终R值为 0 0 7 Mn2 处于变形三角双锥配位环境中 .量子化学计算表明配体具有负电荷空穴 ,使其易于与金属离子配位     

Er2(PhCH2COO)6·4H2O的结构及热分析

用X-射线四圆衍射仪测定了Er_2(PhCH_2COO)_6·4H_2O的晶体结构。配合物属于单斜晶系, 空间群为P2_1/α, 晶胞参数:α=0.9008(3) nm, b=1.4243(5) nm, c=1.8437(7) nm, β=98.80(3)°, V=2.337(1) nm~3, Z=4. 采用TG-DTG-DTA研究了配合物的热分解过程, 确定了热分解机理。采用Freeman-Carroll方法计算了配合物脱水过程的活化能和反应级数。用DSC测定了配合物脱水, 熔化过程的焓变。     

3-(Aryl)-2-sulfanylpropenoates of mercury(II) and phenylmercury(II)

Compounds [HQ]₂[Hg(L)₂] and [HQ][PhHg(L)] [where HQ = diisopropylammonium cation; L = pspa, fspa, tspa, where p = 3-(phenyl), f = 3-(2-furyl), t = 3-(2-thienyl), and spa = 2-sulfanylpropenoato] have been prepared by the reaction of mercury(II) acetate or phenylmercury(II) acetate with the corresponding acid in the presence of diisopropylamine in ethanol. The compounds have been characterized by elemental analysis, FAB mass spectrometry and IR and NMR (¹H, ¹³C) spectroscopy. The crystal structures of the [HQ]₂[Hg(L)₂] compounds show the presence of diisopropylammonium cations and [Hg(L)₂]²⁻ anions. In each anion the Hg atom is in an HgO₂S₂ environment and this can be described as nido-tbp. The crystal structures of the [HQ][PhHg(L)] compounds show the presence of diisopropylammonium cations and [PhHg(L)]⁻ anions in which the Hg atom adopts an HgCOS distorted T-environment. The NMR data suggest that the coordination mode of the ligand L²⁻ determined by X-ray diffractometry in the solid remains in solution.     

SYNTHESIS,CHARACTERIZATION AND CRYSTAL STRUCTURE OF A COMPLEX OF EUROPIUM PERCHLORATE WITH METHYLENE BIS(DIPHENYLPHOSPHINE OXIDE)

Abstract

A complex of europium perchlorate with methylene bis(diphenylphosphine oxide) (HMPPO), [Eu(HMPPO)₄](ClO₄)₃·2H₂O has been synthesized and characterized by X-ray crystallography, infrared spectroscopy and thermal analysis. The X-ray structure of the complex shows Eu(III) is coordinated by eight oxygen atoms from four HMPPO ligands, forming a distorted square antiprism coordination geometry. The complex crystallizes in space group P-1 with cell parameters a = 15.807(3), b = 17.868(4), c = 20.656(4) Å, α = 86.85(3)°, β = 82.33(3)°, γ = 66.75(3)°. The final R_l and R_w are 0.0803 and 0.1994, respectively, for 9540 observed reflections [I > 2[sgrave](I)]. Its luminescent properties have also been studied.     

SYNTHESIS AND MORPHOLOGICAL STRUCTURE OF POLY (PHENYLENE SULFIDE AMIDE)

Poly (phenylene sulfide amide) (PPSA) has been synthesized by using sulfur as Ssource which reacts with dichlorobenzamide (DCBA) and alkali in polar organic solvent atthe atmospheric pressure. The polymer structures were determined by elemental analysis,FT-IR and ~1H-NMR. It is shown that the yielded polymer has linear structure and itsstructure unit is -p-C_6H_4-CONH-p-C_6H_4-S-. The polymer morphology was studied byX-ray diffraction and polarized microscopy. The results show that PPSA is a crystallinepolymer and its spherulites are the aggregation of nontwisting lamella or micro-threadstructure. Under shearing force, these crystals are dispersed to form micro-fibrillarstructure. The decomposition kinetics of PPSA was also studied at different beating rates.The decomposition energy of PPSA is higher than that of PPS.