Synthesis, crystal structure, and properties of the adduct of bis(O,O′-diisopropyl dithiophosphato)nickel(II) with pyridine [Ni(i-Pr2dtp)2(py)2]

A new adduct bis(pyridine)-bis(O,O-diisopropyl dithiophosphato-S,S)nickel(II), [Ni(i-Pr₂dtp)₂(py)₂] (dtp = dithiophosphate, py = pyridine) has been obtained by re-crystallization from CH₃COCH₃. The crystal and molecular structure of the title complex has been determined by X-ray crystallography. It crystallizes in the monoclinic system, space group P2₁/c, with lattice parameters a = 6.4890(13) Å, b = 16.386(3) Å, c = 14.830(3) Å, = 99.74(3)°, V = 1554.1(5) ų, and Z = 2. The crystal structure consists of discrete molecules of [Ni(i-Pr₂dtp)₂(py)₂], which displays a slightly distorted octahedral geometry for the NiS₄N₂ chromophore. Two O,O-diisopropyl dithiophosphate ions act as bidentate ligands with their S atoms coordinated to Ni atom. Each forms a four-membered chelate ring in the equatorial plane. The N atoms from two pyridine ligands are axially coordinated to the Ni atom. The Ni S bond distances are 2.4492(8) Å and 2.5711(9) Å, and the Ni bond distances are 2.127(3) Å. Thermal analyses show that the thermal decomposition of this adduct is so unstable that loss of two pyridine ligands begins at about 65°C. Electronic and IR spectra data is in agreement with the structural data.     

Synthesis and crystal structure of trans-bis(O, O′-diisopropylthiophosphoryl-1H-imidazole-N3) bis(O,O′-diisopropyldithiophosphato) nickel(II) complex: Ni[N3-ImSP(OiPr)2]2[S2P(OiPr)2]2 (Im = imidazole; iPr = isopropyl)

The mononuclear complex, Ni[N³-ImSP(OiPr)₂]₂[S₂P(OiPr)₂]₂ (Im = imidazole; iPr = isopropyl), was unexpectedly obtained in a reaction of bis(O,O-diisopropyl-dithiophosphato) nickel(II) complex with imidazole ligand, and its structure was determined by X-ray crystallography. It crystallizes in the triclinic system, space group P , with lattice parameters a = 12.437(3) Å, b = 13.181(3) Å, c = 8.4580(17) Å, = 93.16(3)°, = 101.93(3)°, = 65.26(3)°, and Z = 1. The Ni atom has almost perfect octahedral coordination geometry and is coordinated by two N atoms of imidazole from two O,O-diisopropylthiophosphoryl-1H-imidazole ligands in axial positions and four S atoms from two (O,O-diisopropyldithiophosphato) anions which act as bidentate ligands forming a four-membered chelate ring in the equatorial plane. The Ni—S bond distances are 2.469(1) and 2.507(1) Å, and the Ni—N bond distances are 2.097(2) Å. The IR spectra data are in agreement with the structural data.     

Structure of the adduct of bis(2,2′biimidazole)copper(II) perchlorate with 4,7-dihydro-1,2,4-triazolo[1,5-a]pyrimidine-7-one

The crystal structure of the compound [Cu(biim)₂](ClO₄)₂(7HtpO)₂ (where 7HtpO is 4,7-dihydro-1,2,4-triazolo[1,5-a]pyrimidine-7-one and biim is 2,2'biimidazole) has been determined at room temperature. The dark green crystals are monoclinic, space group C2/c with unit dimensions a = 19.666(2) Å, b = 11.7586(8) Å, c = 13.4808(9) Å, = 103.690(8)°, Z = 4, and Dx = 1.761 Mg-m^–3. The structure was refined by a full-matrix least-squares procedure on F ² to final R = 0.0806 using 4407 reflections. The cation is slightly distorted square planar and 7HtpO is not directly linked to the metal, the interaction between the cation and the triazolopyrimidine moiety taking place via stacking.     

Structure and molecular chirality of the acetonitrile adduct of the 2:1 salt of quinidine with biphenyl 5,5′-dinitro-2,2′-dicarboxylic acid (5,5′-dinitrodiphenic acid)

The molecule of the 21 salt consists of two quinidine cations and the 5,5-dinitrodiphenic anion. Both of the quinidine cations are protonated at the nitrogen atoms of the quinuclidine fragments. Owing to the interlocking hydrogen bonds between quinidine and the dinitrodiphenic ions, a rigid structure of the salt molecule has been formed. The alkaloid molecular conformation around the C(8)-C(9) bond is open. The conformational parameters of 5,5-dinitrodiphenic anion are considerably changed in comparison with the conformation of diphenic acid in the solid state. The absolute configuration of biphenyl 5,5-dinitro-2,2-dicarboxylic anion (R) is defined by the negative torsion angles around the line which connects the centers of both phenyl rings, and is the reverse of that observed in the diphenic acid-quinine salt. The present data confirm the observation that the chirality of the salt is controlled by the chirality of theCinchona alkaloid molecule.     

Self-assemblies of Ni(II) with phenanthroline and maleate anions: [Ni(H2O)3(phen)L] ⋅ H2O (1) and [Ni(H2O)2(phen)L] ⋅ 2H2O (2) with H2L = maleic acid

The complex [Ni(H₂O)₃(phen)(C₄H₂O₄)] H₂O (1), which was obtained by reaction of phenanthroline, Ni(NO₃)₂ 6H₂O, and maleic acid in CH₃OH/H₂O at pH = 7.05, crystallized in the monoclinic space group P2₁ (no. 4) with cell dimensions: a = 9.350(1) Å, b = 7.631(1) Å, c = 12.821(1) Å, = 106.25(1), and D _calc = 1.607 g/cm³ for Z = 2. The Ni atoms are each octahe drally coordinated by one chelating phen ligand, three H₂O molecules and one monodentate maleato ligand to form [Ni(H₂O)₃(phen)(C₄H₂O₄)] complex molecules with d(Ni–O) = 2.038–2.090 Å, d(Ni–N) = 2.066, 2.089 Å. The formed complex molecules are, via the intermolecular hydrogen bonds, assembled into columnar 1D chains. Interdigitation of the chelating phen ligands of the neighboring chains leads to 2D layers and the crystal H₂O molecules are hydrogen bonded to the oxygen atoms of the maleate not coordinated to the Ni atom. However, reaction of NiCO₃, phen, and maleic acid in CH₃OH/H₂O at pH = 6.33 afforded [Ni(H₂O)₂(phen)(C₄H₂O₄)] 2H₂O (2), which crystallized in the triclinic space group (no. 2) with cell dimensions: a = 7.971(1) Å, b = 8.237(1) Å, c = 13.304(1) Å, = 81.005(6)°, = 87.877(8)°, = 78.322(8)°, and D _calc = 1.671 g/cm³ for Z = 2. The Ni atoms are each octahedrally coordinated by two N atoms of one phen ligand and four O atoms of two H₂O molecules and two bis–monodentate maleato ligands with d(Ni–O) = 2.041–2.120 Å and d(Ni–N) = 2.095 Å. The Ni atoms are bridged by the maleato ligands to generate 1D ¹ [Ni(H₂O)₂(phen)(C₄H₂O₄)_2/2] chains along [100]. The supramolecular assemblies of the 1D chains via – stacking inter- actions result in thick 2D layers parallel to (001), between which the noncoordinating H₂O molecules are sandwiched. The paramagnetic [Ni(H₂O)₂(phen)(C₄H₂O₄)_2/2] 2H₂O (2) obeys the Curie–Weiss law _m(T-) = 1.139cm³ mol^–1 K with the Weiss constant = –0.95 K.     

Structure of bis(O,O′-diisopropyldithiophosphato-S,S′) (1,10-phenanthroline-N1,N10)zinc(II) complex, [Zn(phen)(S2P(OiPr)2)2]

The crystal and molecular structure of [Zn(phen)(S₂P(OiPr)₂)₂] (Phen = 1,10-phenanthroline) has been determined by X-ray crystallography. It crystallizes in the Monoclinic system, space group C2/c, with lattice parameters a = 19.315(4), b = 10.438(2), c = 16.567(3)Å, = 102.89 (3)°, and Z = 4. The complex has C₂ symmetry. The coordination geometry of each Zn atom, by two S atoms from two (O,O-diisopropyldithiophosphato) anions and by two N atoms from phenanthroline ligand, is that of a slightly distorted tetrahedron [Zn—S 2.2914(8)Å Zn—N 2.111(2)Å]. The Zn···S distances to the noncoordinated S atoms are long: 3.5276 Å, which are indicated that there are much weaker interactions between them.     

Synthesis and structure of [(nitrito-O,O′) bis(di-2-pyridylamine)copper(II)] nitrite

The synthesis and molecular structure of the title compound, [(nitrito-O,O) (dpa)₂Cu(II)] (NO₂), 1, is reported. Compound 1 crystallized in the orthorhombic space group Pccn with a = 11.397(5) Å, b = 12.256(6) Å, c = 14.876(8) Å, and V = 2077.9(17) ų with Z = 4. The distorted octahedral copper(II) cations are linked through a hydrogen-bonded polymer network. The polymer network is formed through the amine N–H of the cations and hydrogen bonded to the N–HO nitrite anions.     

Growth,Properties, and Structure of Cadmium Sulfamate Cd(NH2SO3)2 · 2H2O

Crystallography Reports - The temperature dependence of the solubility of Cd(NH2SO3)2 compound in the range from 25 to 80°C has been determined. It is found that Cd(NH2SO3)2 · 2H2O and...     

Crystal and molecular structure of the spin-crossover complex bis(pyridine) [N,N′-ethylenebis (3-carboxysalicylaldimine)] cobalt (II)

The average structure of the title compound, Co(H₂fsa₂en)(py)₂, which has been shown previously to exhibit a thermally induced high-spin low-spin crossover, has been investigated by single-crystal X-ray diffraction. This structure has been solved in the monoclinic space groupC2/c (No. 15), with cell dimensionsa=16.641(5),b=9.496(4),c=16.329(6) Å, and=95.47(3)°;V=2569(3) ų,M _r =571.46,Z=4,D _x =1.478 mg m^–3; MoK radiation (graphite crystal monochromator),=0.71073 Å,(MoK)=7.138 cm^–1;T=295 K andR=0.081 for 681 observed [I>3(I)] independent reflections. The cobalt(II) ion resides on a twofold axis in an elongated octahedral environment, the length of the apical bond (formed with pyridine) being 2.262(12) Å and the mean length of the equatorial bonds (formed with the Schiff base) 2.079(12) Å. These values are consistent with the magnetic behavior, which suggested a distorted surrounding for the metal atom. The packing is essentially governed by the parallelism of the salicylaldimine ligands. The two pyridine rings of the molecule are twisted by ~98° on each side of the basal plane; they are probably affected by orientational disorder or, if ordered, they might be described in a superstructure not yet established.     

Structure and conformation of the monohydrate of N-t-boctyrosyl-proline (Boc-Tyr-Pro·H2O)

The structure and conformation of the monohydrate of N-t-boc-tyrosyl-proline (Boc-Tyr-Pro·H₂O) (C₁₉H₂₆O₆N₂·H₂O) has been investigated with X-ray crystallographic and spectroscopic methods. Boc-Tyr-Pro crystallized in an extendedtrans conformation in the space group P2₁2₁2₁ with cell dimensionsa=8.566(1),b=9.996(1),c=24.734(1). The conformation of Boc-Tyr-Pro reflex -helix type prolines. Three intermolecular hydrogen bonds are observed. Crystal water is involved in two hydrogen bonds (to the hydroxyl group of the C-terminal of the proline residue; to the carbonyl group of the t-Boc functionality) while the hydroxyl group of the tyrosyl residue (to the carbonyl group of the amide bond) is involved in one hydrogen bond. The puckering mode of the pyrrolidine ring of the proline residue is similar to what has been previously observed for other proline-containing peptides.Cis-trans isomerism is observed in the NMR spectra of Boc-Tyr-Pro with a predominance for the extended side chain for the tyrosyl residue.     

Synthesis,Structure, and Properties of the Tris(ethylendiamine)nickel(II) Dichloride Dihydrate [Ni(H2NCH2CH2NH2)3]Cl2 ⋅ 2H2O Crystals

Crystallography Reports - The conditions for synthesis of [Ni(H2NCH2CH2NH2)3]Cl2 ⋅ 2H2O ([Ni(en)3]Cl2 ⋅ 2H2O) crystals from aqueous solutions have been considered. The synthesized...     

Synthesis and structural characterization of [Co(tren)(Tsal)]ClO4·H2O and [Ni(pn)(py)2(NCS)2]

Complexes [Co(tren)(Tsal)]ClO₄·H₂O 1 and [Ni(pn)(py)₂(NCS)₂] 2, (tren = tris(2-aminoethyl)amine, Tsal = thiosalicylate ion, pn = 1, 2-diamino propane and py = pyridine) have been synthesized and structurally characterized. Both complexes crystallize in the monoclinic space group C2/c with a = 21.3340(6), b = 11.7754(2), c = 14.8076(5) Å, = 100.3831(10)°, Z = 8 (1), and a = 7.2573(8), b = 17.8810(11), c = 15.2681(12) Å, = 101.170(2)°, Z = 4 (2). The metal atoms in both cases have distorted octahedral geometry. In 1, the tren ligand is quadridentate and Tsal is bidentate chelate. In 2, the pn ligand forms a bidentate chelate with the NCS ligands in trans positions. Complex 1 is diamagnetic whereas 2 shows paramagnetism with a magnetic moment of 3.10 B. M.     

Crystal structures of bis(cyanido)bis(N,N′-diethylthiourea-κS) mercury(II) and bis(cyanido)bis(N,N′-dipropylthiourea-κS) mercury(II)

Two mercury(II) complexes containing cyanide and, N,N′-diethylthiourea (detu) and N,N′-dipropylthiourea (dprtu) ligands, [(detu)₂Hg(CN)₂] (1) and [(dprtu)₂Hg(CN)₂] (2), respectively, have been prepared and characterized by X-ray crystallography. In the both complexes Hg atom lies on a 2-fold rotation axis, and is coordinated to the sulfur atoms of two thiourea ligands and to two cyanide carbon atoms. Both have a distorted tetrahedral environment with bond angles about the Hg atoms in the range of 93.41(4)°–146.75(19)°. In the crystal structures symmetry related molecules are linked via N-H-N hydrogen bonds resulting in the formation of a two-dimensional network in 1, while in 2 a double stranded one-dimensional chain is formed.     

Synthesis,Crystal Structure and Characterization of (Z)-2-N′-hydroxyisonicotinamidine

The compound (Z)-2-N′-hydroxyisonicotinamidine, (2) was synthesized and characterized by ¹H NMR, FT-IR, FAB-Mass, UV-Visible Spectra, and elemental Analysis. Its molecular structure was solved by single crystal X-ray diffraction method. The title molecule, C₆H₇N₃O is crystallized in the orthorhombic crystal system with the space group Pna2₁ and with unit cell parameters a = 12.5664(8) Å, b = 8.8622(6) Å, c = 5.7953(4) Å, α = 90°, β = 90°, γ = 90°, and Z = 4. The molecular and crystal structure of the title molecule is stabilized by an intramolecular interaction of the type N—H···O, and the intermolecular interactions of types N—H···N and O—H···N.     

Structure of tetra(β-propiophenone-1,2,4,triazole-N4) dichloro metal hexahydrate complex: [MCl2(C2H2N3CH2CH2COPh)4]⋅6H2O (M = Ni, Co)

The crystal and molecular structures of the complexes of [NiCl₂(N⁴-trzCH₂CH₂ COPh)₄]6H₂O and [CoCl₂(N⁴-trzCH₂CH₂COPh)₄] 6H₂O (trz = 1,2,4-triazole) have been determined by X-ray crystallography. They are isomorphous. The crystal structures are very similar. They both crystallize in the monoclinic system, space group P2 ₁/c, Z = 4; the former with lattice parameters a = 8.0391(2), b = 10.8215(2), c = 29.0133(2) Å, = 94.792(1)°; the latter with a = 8.039(2), b = 10.822(2), c = 29.013(6) Å, = 94.79(3)°. They all display almost perfect octahedral coordination geometry around the central metal atom. Each metal atom is coordinated by four N atoms of triazole from four -propiophenone-1,2,4-triazole ligands and two chloride anions in a trans arrangement. In addition to the coordinating metal complex, there are six uncoordinated water molecules, which complete the crystal structure. In the solid state, the title two compounds form three dimensional network structures through hydrogen bonds. The intermolecular hydrogen bonds connect the [MCl₂(C₂H₂N₃CH₂CH₂COPh)₄] and H₂O moieties.     

Syntheses of 1,1′-Bicobaltocene Salts of Tetracyano-P-Quinodimethane,Tetrabromoquinone, and Tetrabromodiphenoquinone; and the Structure of 1,1′-Bicobaltocene[Co(III)Co(III)][TCNQ]3

Abstract

A general theory of exciton (and electron) transport in perfect molecular crystals is discussed. The emphasis is on qualitative results and the elucidation of the effect of exciton and phonon bandwidth on the scattering of excitons and on transport. Various microscopic models are discussed in this light.     

Magnetic Characterization of the Ferrimagnetic Compounds CoM(M'EDTA)2.4H2o (M,M′ = Co,Ni)

Stimulated by the magnetic behaviors of the title compounds we have developed a general treatment for solving an exchange-coupled Ising chain made up of three magnetic sublattices which are ordered according to the sequence A-B-A—C—A-B-A—C. Exact expressions of the susceptibility and specific heat are derived for S_a=S_b=½ and S_c=3-2, including a local anisotropy on the later sublattice, D_c. The magnetic properties of the CoCo(CoEDTA)₂.4H₂O compound are discussed on the basis of the developed model.     

Structure of hexakis(imidazole)cadmium(II) carbonate trihydrate: [Cd(Im)6]CO3 ⋅ 3H2O

The crystal and molecular structure of the title compound [Cd(Im)₆]CO₃ 3H₂O, where Im = imidazole, has been determined by X-ray crystallography. The crystal structure consists of discrete Cd(Im)₆ ²⁺ cations, CO₃ ^2– anions and three uncoordinated water molecules. It crystallizes in the hexagonal system, space group P6₃/m, with lattice parameters a = 9.0552(l) Å, c = 21.745(l) Å, and Z = 2; The Cd(II) ion assumes centrosymmetric octahedron geometry. The bond distance of Cd–N is 2.361(l) Å. A three-dimensional intermolecular hydrogen bond network is formed between the free carbonate anions, the imidazole ligands, and the free water molecules.     

Structure of 2-(2′-bromo-5′-nitrostyryl)benzothiazole

The title compound C₁₅H₉BrN₂O₂S (brnsb) is monoclinic, witha=7.730(2),b=26.847(5),c=7.773(2) Å,=117.48(1)°,V=1431(1) ų,Z=4,D _x=1.677,(MoK)=29.9 cm^–1,F(000)=720,T=298K in space groupP2₁/c. The structure was solved by heavy atom and Fourier methods and refined toR=0.034 for 1776 unique observed reflections. The molecule is nearly planar, with a dihedral angle of only 3.8(1.1)° between the benzothiazole and phenyl rings. The C-S-C angle in the thiazole ring is 89.0°, while the C-N-C angle in that ring is 111.5(3)°.     

Structure and molecular chirality of the 2∶1 salt of quinine with biphenyl 2,2′-dicarboxylic acid (diphenic acid)

The molecule of the salt consists of two quinine cations and a biphenyl 2,2-dicarboxylic dianion. Both of the quinine cations are protonated at the nitrogen atoms of the quinuclidine fragments. Each carboxylic group of the diphenic dianion acts as a proton donor with respect to the quinuclidine N(1) atom of one of the quinine cations, and as a proton acceptor with respect to the carbinol O(12)-H(12) group of the other. Thus, the interlocking hydrogen-bond system forms a rigid structure. The molecular conformation around the C(8)-C(9) bond is synclinal. The conformational parameters of the diphenic dianion are considerably different from those of diphenic acid in solid state. The absolute configuration of the biphenyl 2,2-dicarboxylic dianion (S) is defined by the positive torsion angle around the line which connects the centers of both phenyl rings. The molecular chirality of the salt arises from the coupling between the quinoline and the biphenyl chromophores, as well as from the coupling of the quinoline-quinoline long-axis polarized-band transition moments.