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The binding modes of 2-((2-aminoethyl)amino)ethanol-based ligands were explored using the Cambridge Structural Database (CSD). To extend this field, a new cadmium complex containing 2-((2-aminoethyl)amino)ethanol (AEAE), [Cd(AEAE)2][Cd(AEAE)2]′[CdI4]2 (1), was prepared and characterized by spectroscopic methods and single-crystal X-ray diffraction. The reaction of AEAE with a 1:1 mixture of CdI2 and HgI2 was also investigated. The complex, [Cd(AEAE)2][I2Hg(μ-I2)2HgI2] (2), was synthesized and characterized. Compounds 1 and 2 represent the first tridentate binding modes of an AEAE type ligand with Cd2+. Geometrical investigation for complexes containing Cd(Namine2Oalcohol)2, CdIn, and HgIn environment were carried out using the CSD software. Also different possible diastereomers which can be formed in coordination of a pair of tridentate AEAE ligands in octahedral geometry were studied and discussed. [ABSTRACT FROM AUTHOR]

Three new metal-organic compounds containing bismuth and pyridine-2,6-dicarboxylate (pydc) formulated as (2-apyH) 2 [Bi(pydc) 2 (pydcH)]·2H 2 O, 1 , (4-apyH)[Bi(pydc) (pydcH) 2 ].4H 2 O, 2 and (pipzeaH)[Bi 2 (pydc) 3 (pydcH) (H 2 O) 2 ]·5H 2 O, 3 , (2-apy = 2-aminopyridine, 4-apy = 4-aminopyridine, pipzea = 2-piperazin-1-ylethanamine), have been synthesized in deionized water and characterized by elemental analysis (C, H and N), spectral (UV–Vis, IR), 1 H NMR spectroscopy, TGA and single crystal X-ray diffraction. These compounds were obtained via proton transfer methodology. Compounds 1 and 2 have similar monomeric bismuth coordination units, whereas compound 3 has a dimeric bismuth coordination unit. The compounds are anionic in 1 and 2 and they are connected non-covalently to 2-apyH and 4-apyH, respectively. In 3, two molecules are present, one neutral and one anionic, and both are connected non-covalently to pipzeaH cations. Five different coordination modes of Bi-pydc exist in 1 , 2 and 3. These compounds are stabilized in the solid state by a complex network of hydrogen bonds between crystallization water molecules, anionic, cationic and neutral fragments, forming 3D-supramolecular arrays. [ABSTRACT FROM AUTHOR]

A new mixed-ligand copper(I) complex [Cu(L)(PPh3)2] (1) of methyl 2-(2-hydroxybenzylidene)hydrazinecarbodithioate (H2L) and triphenylphosphine was prepared and identified by elemental analysis, Fourier transform infrared, Raman,1H,13C,31P NMR, and UV-Vis spectroscopy, molar conductivity, and single-crystal X-ray diffraction. The copper(I) ion in the crystal structure of (1) has a distorted tetrahedral geometry achieved by the coordination of the two phosphorus atoms of triphenylphosphine groups and a nitrogen and sulfur atom of HL−. The intramolecular O–H···N and intermolecular C–H···S hydrogen bonds stabilize the crystal network of (1). In addition to these hydrogen bonds, there are π−π stacking between parallel aromatic rings belonging to the triphenylphosphine groups of adjusting complexes. Three structural surveys, including coordination numbers of the copper atom, coordination modes of ligand, and all reported structures containing hydrazinecarbodithioate Schiff bases are presented. [ABSTRACT FROM AUTHOR]

Abstract: In this work, 2-((2-((2-hydroxyethyl)amino)ethyl)amino)cyclohexanol, HEAC, was prepared in solvent by the ring opening of cyclohexene oxide with 2-(2-amino-ethylamino)ethanol. Four complexes of HEAC, including [Pd(HEAC)Cl2] (1), [Cd2(HEAC)2(μ-Br)2Br2] (2), [Cd(HEAC)(OAc)2] (3) and [Hg(HEAC)Cl2] (4), were prepared and identified by elemental analysis, FT-IR, Raman, 1H NMR spectroscopy and single-crystal X-ray diffraction. Redox properties of HEAC before and after complexation were investigated in DMSO. In the crystal structure of HEAC, the two hydroxyl arms are trans to each other and the cyclohexane ring has a chair conformation with two C-chiral centers. Two new N-chiral centers are produced during the complexation process. In the crystal structure of 1, the palladium atom has a distorted square planar PdN2Cl2 environment. X-ray analysis of 2 reveals a dimer structure containing two bromide bridges. Each cadmium atom in 2 is found to be in a CdN2OBr3 distorted octahedral environment. The Cd2(μ-Br)2 moiety is placed on a plane and forms a parallelogram. The complex has a center of inversion at the center of the parallelogram and Ci symmetry. In the crystal structure of 3, the cadmium atom with a CdN2O5 environment has a distorted capped trigonal prismatic geometry. Complex 4 also has a distorted square-pyramidal geometry (HgN2OCl2). In the networks of HEAC and the complexes 1–4, intermolecular hydrogen bonds form different types of hydrogen bond motifs between adjacent molecules. [Copyright &y& Elsevier]

Two complexes of dimethyl pyridine-2,6-dicarboxylate (L), [CdL3][Cdl4] (1) and [Ag(L)NO3]n (2) were prepared and identified by elemental analysis, FT-IR, Raman and 1H NMR spectroscopy, cyclic voltammetry, and single-crystal X-ray diffraction. The crystal structure of 1 contains both complex cation and complex anion of the metal. Cadmium in [Cdl3]2+, coordinated by three nitrogens and six oxygens, has a distorted tricapped trigonal prismatic geometry while [Cdl4]2-, with four coordinated iodides, has a slightly distorted tetrahedral geometry. In the crystal structure of 2, silver has distorted tetrahedral geometry by coordination of nitrogen and three oxygens. One oxygen of nitrate in 2 bridges two silvers. Extension of these bridges forms a 1-D coordination polymer. Cyclic voltammetry of L reveals two reduction steps which are shifted after coordination in 1, while no significant shifts are observed in 2. Hydrogen bonds including C-H... I, C-H...O and C-H... C and short interactions such as C... I, π... π, and π ... O are compared with Cambridge Structural Database analogs. Two brief structural surveys on ligand coordination modes and silver polymers are also presented. [ABSTRACT FROM AUTHOR]

Template reaction of copper(II) nitrate with N-(2-aminoethyl)-1,3-diaminopropane and formaldehyde yields a macrocyclic copper(II) complex of 1,3,6,10,12,15-hexaazatricyclo[13.3.1.16,10]eicosane (L), [CuL(NO3)2] (1). Replacement of nitrate with perchlorate gives [CuL(ClO4)2] (2). These complexes have been characterized by FT-IR and Raman spectroscopies, electronic absorption, cyclic voltammetry, and X-ray crystallography. The crystal structure of 1 shows that copper has distorted octahedral geometry with two secondary and two tertiary amines of the macrocycle and two oxygen atoms from nitrate coordinating the axial positions. The copper in 2 has the same geometry with axial positions occupied by one oxygen atom of perchlorate. Copper lies on the plane of four coordinated nitrogen atoms and there is no rms deviation from this plane. Cyclic voltammetry of 1 and 2 gives two one-electron waves corresponding to CuII/CuIII (−0.75, −0.72) and CuII/CuI (0.48, 0.24) processes. For understanding of geometry parameters in diazacyclam-based copper(II) complexes, a survey on complexes from CSD structures is presented. In this study the macrocycle hole size was estimated by ionic radii of metal ions located inside of it. [ABSTRACT FROM PUBLISHER]

The reaction of isatin-3-thiosemicarbazone (ITC, 1) or isatin-3-semicarbazone (ISC, 2) with nitrato bis(triphenylphosphine)copper(I) gave the four coordinate copper(I) complexes [Cu(PPh3)2(ITC)]NO3 (3) and [Cu(PPh3)2(ISC)]NO3 (4). The synthesized complexes were characterized by FT-IR, UV-VIS, Raman and elemental analysis. The crystal structure of 3 was investigated by single crystal X-ray diffraction. The ITC coordinates to the copper(I) ion in a bidentate fashion via the N(imine) and S atoms which along with two triphenylphosphine ligands form a tetracoordinate complex. The complex has a distorted tetrahedral coordination environment. Crystal data at 150.0 K: space group P21/c with a=12.5777(4), b=15.2062(5), c=21.9057(7) Å, β=95.628(3)o, Z=4, R1=0.049. [image omitted] [ABSTRACT FROM AUTHOR]

The ligand 3,4-diamino-5-methyl-4H-1,2,4-triazole (DAMT) and its trinuclear cadmium complex [Cd3(DAMT)2(DAMTH)2Cl8] have been prepared and identified by elemental analyses, infrared, Raman, 1H and 13C NMR spectroscopy, and single crystal X-ray diffraction. The protonation equilibria of the ligand have been studied by pH-potentiometry, with pK1 13.29 and pK2 5.40 determined. The free ligand consists of triazole cations (DAMTH) and chloride counter ions. The neutral cadmium compound is a complex of the cationic ligand in which three Cd's are coordinated by two unidentate cation forms of the ligands (DAMTH), two ambidentate neutral forms of the ligand (DAMT), and eight chlorides. Cadmium ions have slightly distorted octahedral geometry. [ABSTRACT FROM AUTHOR]

Two new compounds, N-(2-aminoethyl)piperazinium trinitrate (AEPH3(NO3)3) and N-(2-hydroxyethyl)piperazinium dinitrate (HEPH2(NO3)2), were prepared. IR spectra of AEPH3(NO3)3 and HEPH2(NO3)2 were compared with those of the parent N-(2-aminoethyl)piperazine (AEP) and N-(2-hydroxyethyl)piperazine (HEP), respectively. The intermolecular interactions affect the symmetry of the nitrate ions in AEPH3(NO3)3 and HEPH2(NO3)2, lowering it from D3h to C2v or Cs. Single-crystal X-ray diffraction of AEPH3(NO3)3 showed that the piperazine moiety has a chair conformation and that two of its nitrogen atoms have a distorted tetrahedral geometry. Similar results were observed for HEPH2(NO3)2. In the crystals, there are NO contacts between nitrate groups and hydrogen bond motifs between nitrate and ammonium groups (only in AEPH3 (NO3)3). [ABSTRACT FROM AUTHOR]