Top PDF Aqua­(2,2′ bipyrid­yl)(pyrazine 2,6 di­carboxyl­ato)nickel(II) 1 25 hydrate

Aqua­(2,2′ bipyrid­yl)(pyrazine 2,6 di­carboxyl­ato)nickel(II) 1 25 hydrate

Aqua­(2,2′ bipyrid­yl)(pyrazine 2,6 di­carboxyl­ato)nickel(II) 1 25 hydrate

Data collection: SMART Bruker, 1997; cell refinement: SAINT Bruker, 1997; data reduction: SAINT; programs used to solve structure: SHELXTL Sheldrick, 2008; programs used to refine struct[r]

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Poly[[μ2 aqua tetra­aquahexa­kis­(μ4 naph­thalene 2,6 di­carboxylato)tetra­holmium(III)] 1 75 hydrate]

Poly[[μ2 aqua tetra­aquahexa­kis­(μ4 naph­thalene 2,6 di­carboxylato)tetra­holmium(III)] 1 75 hydrate]

atoms which occupy the capping positions of the coordination polyhedra, the remaining Ho—O distances are typical and well within the ranges registered for related materials (as revealed by a search in the CSD - 77 entries, range of 2.20–2.82 Å with a median of 2.34 Å): for Ho1 to Ho4, respectively, 2.277 (8)–2.370 (8) Å, 2.264 (8)–2.423 (9) Å, 2.299 (7)– 2.469 (8) Å and 2.276 (7)–2.453 (10) Å (Table 1). We emphasize that even though the Ho—O distances associated with these capping positions are unusually long, they are still within the feasible range found in related materials. Moreover, we also note that the longest values of Ho—O for Ho1 to Ho4 found in the ranges given above are those with the coordinated water molecules. In fact, by restricting the search in the CSD to the geometrical parameters for coordinated water molecules to Ho 3+ centres, the expected range is from 2.28 to 2.55 Å, which is in good agreement with the
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Bis{4 [(E) 2 (1H indol 3 yl)ethen­yl] 1 methyl­pyridinium} 4 fluoro­benzene­sulfonate nitrate 0 25 hydrate†

Bis{4 [(E) 2 (1H indol 3 yl)ethen­yl] 1 methyl­pyridinium} 4 fluoro­benzene­sulfonate nitrate 0 25 hydrate†

4-[(E)-2-(1H-Indol-3-yl)ethenyl]-1-methylpyridinium iodide (compound A) was synthesized from a mixture (1:1:1 molar ratio) of 1,4-dimethylpyridinium iodide (2.00 g, 8.51 mmol), indole-3-carboxaldehyde (1.24 g, 8.51 mmol) and piperidine (0.84 ml, 8.51 mmol) in methanol (40 ml) under reflux for 2 h under a nitrogen atmosphere. The solid which formed was filtered, washed with ether and recrystallized from methanol to give orange single crystals of compound A after several days. The title compound was synthesized by mixing compound A (0.72 g, 2.0 mmol) in hot methanol (30 ml) and silver(I) 4-fluorobenzenesulfonate (0.57 g, 2.0 mmol) in hot methanol (20 ml). The mixture turned yellow and
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Crystal structure of ethyl­ene­di­oxy­tetra­thia­fulvalene 4,5 bis­­(thiol­benzoic acid) 0 25 hydrate

Crystal structure of ethyl­ene­di­oxy­tetra­thia­fulvalene 4,5 bis­­(thiol­benzoic acid) 0 25 hydrate

methanol (6 ml) and THF (6 ml) were added to generate a suspension. In a separate flask, sodium hydroxide (230 mg, 5.8 mmol) was dissolved in degassed water (4 ml). The sodium hydroxide solution was added to compound 2 and the reaction was heated to reflux for 8 h. The reaction was then cooled to room temperature and the volatiles were removed in vacuo. Hydrochloric acid (1 mol l 1 , 15 ml) was added to afford a maroon precipitate, which was collected by filtration and washed with water (50 ml). The product was collected and dried under high vacuum for 12 h to afford 1 as a maroon solid (179 mg, 0.35 mmol, 70% yield). 1 H NMR [DMSO-d 6 ,
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Tenulin 0 25 hydrate, a sesquiterpene lactone isolated from Helenium amarum

Tenulin 0 25 hydrate, a sesquiterpene lactone isolated from Helenium amarum

2a,4a,5,6,6a,9a,9b,9c-octahydro-2H-1,4-dioxadicyclopent- [cd,f]azulene-3,9-dione 0.25-hydrate], a natural product isolated from Helenium amarum, contains two independent tenulin molecules and half a water molecule of crystallization situated on a twofold rotation axis. The hydroxy group of the hemiketal moiety is in a -position. In the crystal, each water molecule interacts with four tenulin molecules via O—H O hydrogen bonds. The two independent tenulin molecules (A and B) differ only in the character of their participation in hydrogen bonding. Specifically, while A is an acceptor of O water —H O A and a donor of O A —H O B hydrogen
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Bis(tetra­butyl­ammonium) bis­­(3,4,5 trioxo­cyclo­pent 1 ene 1,2 di­thiol­ato κ2S,S′)cadmate(II) 0 25 hydrate

Bis(tetra­butyl­ammonium) bis­­(3,4,5 trioxo­cyclo­pent 1 ene 1,2 di­thiol­ato κ2S,S′)cadmate(II) 0 25 hydrate

anion and a 0.25-hydrate water. The anion is composed of a bidentate coordinated 3,4,5- trioxocyclopent-1-ene-1,2-dithiolate (dtcroc) group forming a distorted tetrahedral configuration around the Cd II ion. The dihedral angle between the least-squares planes of the ten- atom sulfur-substituted croconate groups in the anion is 84.10 (8) . The crystal packing is stabilized by weak C—H O and C—H S cation–anion hydrogen-bond interactions. In each of the two cations one butyl group is disordered over two positions in the ratios 0.589 (11):0.411 (11) and 0.796 (12): 0.204 (12).
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(E) N′ (4 Pyridylmethyl­ene) 4 (8 quinol­yl­­oxy)butanohydrazide 0 25 hydrate

(E) N′ (4 Pyridylmethyl­ene) 4 (8 quinol­yl­­oxy)butanohydrazide 0 25 hydrate

the corresponding O3—C29—C30—C31—C32—N6—N7—C33 bond sequence. Despite these differences, the dihedral angles between the mean planes of the pyridine and quinoline rings are not very different, i.e. 67.4 (3)° and 68.0 (2)° for the molecules containing atoms O1 and O3, respectively. The two independent molecules are linked to a supermolecular 2D array via N—H···N hydrogen bonds supported by C—H···O contacts, Table 1. Each partially occupied water

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Bis(nicotinamidium) bis­­[(2R,3R) tartrate] 1 25 hydrate: cations incorporated into hydrogen bonded arrays of anions and water mol­ecules

Bis(nicotinamidium) bis­­[(2R,3R) tartrate] 1 25 hydrate: cations incorporated into hydrogen bonded arrays of anions and water mol­ecules

The asymmetric unit of the title compound, (I), contains two nicotinamidium cations (A and B), two (2R,3R)-tartrate anions (1 and 2), an ordered water molecule, and a disordered water molecule with a partial occupancy of 0.25 (Fig. 1). De- protonation of the anions and protonation of the cations are confirmed by the C—N and C—O bond distances (Table 1). The characteristic features of the nicotinamide structure are the twisting of the carboxamide plane out of the pyridine ring plane (2–40 ) and the deviation of the pyridine N atom from

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Bis(1H benzimidazole κN3)bis­­(4 hy­droxy­benzoato κO)zinc(II) 0 25 hydrate

Bis(1H benzimidazole κN3)bis­­(4 hy­droxy­benzoato κO)zinc(II) 0 25 hydrate

As part of our ongoing investigation into the nature of – stacking in metal complexes, we have prepared a series of phases incorporating aromatic ligands such as quinoline (Pan & Xu, 2004) and benzimidazole (bzim) (Li et al., 2005; Zheng et al., 2005). We present here the title mixed-ligand Zn II complex, (I) (Fig. 1), for comparison with the structures reported previously.

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N,N,N′,N′ Tetra­methyl­butane 1,4 di­ammonium bis­­(p amino­benzoate) 2 25 hydrate

N,N,N′,N′ Tetra­methyl­butane 1,4 di­ammonium bis­­(p amino­benzoate) 2 25 hydrate

The structures of the cations, anions and water molecules of (I), with the labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are represented as small spheres of arbitrary radius and hydrogen bonds are shown as dashed lines. H atoms not involved in hydrogen bonds, the minor component of the disordered TMBDA and the disordered water molecule have been omitted for clarity. [Symmetry codes: (i) 1 x, 2 y, 1 z; (ii) 1

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Aqua­[N,N′,N′′,N′′′ tetra­kis­(2 hy­droxy­ethyl) 1,4,7,10 tetr­aza­cyclo­do­decane κ4N]­neodymium(III) tris­­(perchlorate) 1 25 hydrate

Aqua­[N,N′,N′′,N′′′ tetra­kis­(2 hy­droxy­ethyl) 1,4,7,10 tetr­aza­cyclo­do­decane κ4N]­neodymium(III) tris­­(perchlorate) 1 25 hydrate

coordinated (O5) and solvent water molecules (O1W and O2W) were re®ned independently with isotropic displacement parameters, but the OÐH distances were restrained to be 0.840 (1) AÊ. The intra- molecular H H distances of both solvent water molecules were restrained to be the same. The H atoms of the half-occupancy water molecule (O3W) were placed in calculated positions so as to give sensible hydrogen-bonding geometry, but their coordinates were not re®ned; U iso = 1.5U eq (O3W). The highest peak in the ®nal difference

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Bis[1,3 bis­­(1 methyl 1H benzimidazol 2 yl) 2 oxa­propane]­cadmium dipicrate aceto­nitrile sesquisolvate 0 25 hydrate

Bis[1,3 bis­­(1 methyl 1H benzimidazol 2 yl) 2 oxa­propane]­cadmium dipicrate aceto­nitrile sesquisolvate 0 25 hydrate

ion is coordinated by four N atoms and two O atoms from two tridentate 1,3-bis(1-methyl- 1H-benzimidazol-2-yl)-2-oxopropane ligands in a distorted octahedral coordination environment. The lengths of the chemically equivalent Cd—O bonds [2.4850 (16) and 2.5488 (16)A ˚ ] are signiificantly different. One of the picrate anions is disordered over two sets of sites, with refined occupancies of 0.504 (15) and 0.496 (15). A 0.5-occupancy acetonitrile solvent molecule is disordered over two sites with equal occupancies. The H atoms of a 0.25-occupancy solvent water molecule were neither located nor included in the refinement.
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catena Poly[[[(1,10 phenanthroline)nickel(II)] μ 4,4′ oxydibenzoato] 0 25 hydrate]

catena Poly[[[(1,10 phenanthroline)nickel(II)] μ 4,4′ oxydibenzoato] 0 25 hydrate]

two bidentate oba ligands and two N atoms from a chelate phen ligand to furnish a highly distorted octahedral coordi- nation environment (Fig. 1). The NiÐO bond lengths are in the range 2.0492 (18)±2.1469 (19) AÊ. The trans angles of the octahedron are 159.55 (9), 159.78 (8) and 163.88 (8) , and the

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catena Poly­[[bis­­(pyridine κN)­cobalt(II)] μ oxalato] 0 25 hydrate]

catena Poly­[[bis­­(pyridine κN)­cobalt(II)] μ oxalato] 0 25 hydrate]

Oxalate-bridged polynuclear metal complexes have been the focus of intensive research due to their interesting magnetic properties. The latter are highly dependent on the nature of the metal ion, the peripheral ligand and/or the counter-ion (Castillo et al., 2003, and references therein). The ability of the oxalate moiety to connect to metal ions as a bis-bidentate bridging ligand enables the formation of diverse `supramol- ecular' polymeric assemblies with different dimensionalities (Kitagawa et al., 1995; Decurtins et al., 1994). Indeed, the coordination pattern has pronounced in¯uence on the magnetic behavior of such materials. Although a large number of two- and three-dimensional networks consisting of metal- bridged oxalate complexes are known, only a small number of homometallic one-dimensional systems have been structurally characterized (Castillo et al., 2001, and references therein). We report here a precise crystallographic characterization of the title compound, (I), in which pyridine ligands occupy the ®fth and sixth coordination sites around the octahedral cobalt(II) ion (Fig. 1). The zigzag-type polymerization pattern of (I), illustrated in Fig. 2, resembles that observed in closely related compounds [Castillo et al. (2001); wherein the 3-amino- pyridine analog of (I) has been determined with low preci- sion]. Each chain propagates and lies on consecutive inversion centers, along the a axis The crystal packing of the polymeric entities, parallel to one another, is shown in Fig. 3. Noteworthy are the elongated CÐC bonds in the oxalate groups (Table 1), a result of their geometric requirement to occupy two coor- dination sites of the central cobalt ion.
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Bis(benzimidazole)bis­­(4 hy­droxy­benzoato)cobalt(II) 0 25 hydrate

Bis(benzimidazole)bis­­(4 hy­droxy­benzoato)cobalt(II) 0 25 hydrate

(Fig. 2). The shorter face-to-face separation of 3.28 (5) A ˚ clearly indicates the existence of – stacking between the bzim ligands. Conversely, the distances from the C atoms of the hbz C32-benzene ring to the nearby C32 v -benzene mean plane [symmetry code: (v) 1 x, y, 1

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Theobrominium perchlorate dibenzo 18 crown 6 3 25 hydrate

Theobrominium perchlorate dibenzo 18 crown 6 3 25 hydrate

of theobrominium (3,7-dimethyl-2,6-dioxo-1H-purin-9-ium) cations, perchlorate anions and dibenzo-18-crown-6 and water molecules. The crown ether is in a bent conformation, in which the planes of the aromatic rings subtend an angle of 63.7 (1) . Intermolecular O—H O hydrogen bonding between the water molecules and the O atoms of the cyclic ether delimit an empty space reminiscent of a hollow cage. The water molecules are additionally linked to the cations by N— H O hydrogen bonding. One of the positions of the water molecules is occupied only fractionally (25%) and is located outside this framework.
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Bis(2,5 di­hydroxy­benzoato κO)bis­­(1,10 phenathroline κ2N,N′)cadmium(II) 1 25 hydrate

Bis(2,5 di­hydroxy­benzoato κO)bis­­(1,10 phenathroline κ2N,N′)cadmium(II) 1 25 hydrate

The centroid-tocentroid distance of 3.809 2Å between nearly parallel N1-pyridine and C2i-benzene rings dihedral angle 4.89 17°; symmetry code: i x-1, y, z and the centroid-to-centroid di[r]

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Di­aqua­bis­(1,10 phenanthroline)­cobalt(II) diorotate 2 25 hydrate

Di­aqua­bis­(1,10 phenanthroline)­cobalt(II) diorotate 2 25 hydrate

distance is 2.1089 (13) AÊ and CoÐN distances lie in the range 2.1216 (15)±2.1300 (14) AÊ (Table 1). The geometry of the phen ligand is comparable to that observed in a phen-containing cobalt complex (HoÈkelek & NecefogÆlu, 1997). The unique orotate anion in the asymmetric unit carries a single negative charge and is not coordinated to Co. The orotate moieties are

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2′,6′ Bis(4 carb­­oxy­phen­yl) 4,4′ bipyridin 1 ium nitrate 0 25 hydrate

2′,6′ Bis(4 carb­­oxy­phen­yl) 4,4′ bipyridin 1 ium nitrate 0 25 hydrate

In the title compound (Fig. 1), the central pyridine ring of the cation is almost coplanar with one benzene ring, making a dihedral angle of 1.03 (5)°, while it makes dihedral angles of 9.59 (5)° with the other benzene ring and 13.66 (6)° with the protonated pyridinium ring. N—H···O and O—H···O hydrogen bonds link the organic cations and nitrate anions into a one-dimensional ribbon along [0 1 0] (Fig. 2). The crystal structure also exhibits π–π interactions between the central pyridine rings and the benzene rings of neighboring molecules [centroid–centroid distance = 3.6756 (13) Å].
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Ethyl 4 hy­dr­oxy 1 methyl 5 oxo 2 phenyl­pyrrolidine 3 carboxyl­ate 1 25 hydrate

Ethyl 4 hy­dr­oxy 1 methyl 5 oxo 2 phenyl­pyrrolidine 3 carboxyl­ate 1 25 hydrate

The C-bound hydrogen atoms were located in calculated positions and refined in a riding mode with C—H distances of 0.95–1.00 Å. The O-bound H atoms were found in a difference Fourier map and refined with distance restraints of O—H = 0.88 (2) and H···H = 1.41 (1) Å (for the water molecules) and O—H = 0.84 (2) Å (for the hydroxyl groups). For all hydrogen atoms, U iso were set to 1.2–1.5U eq (carrier atom). The most disagreeable reflections with delta(F 2 )/e.s.d. >10

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