A zwitterionic viologen disulfonate–hydroquinone charge‐transfer crystal: 2,2′‐(4,4′‐bipyridinium‐1,1′‐diyl)di(ethanesulfonate)–hydroquinone (1/2)

The structure of the title compound, C₁₄H₁₆N₂O₆S₂·2C₆H₆O₂, consists of 2,2′‐(4,4′‐bipyridinium‐1,1′‐diyl)di(ethanesulfon­ate) mol­ecules (with crystallographically imposed twofold symmetry) that are hydrogen bonded to each other, as well as to hydro­quinone mol­ecules, in a complex three‐dimensional motif. The orange color of the crystals is indicative of the donor–acceptor interaction between the electron‐rich hydro­quinone π‐donor and the electron‐deficient bipyridinium π‐acceptor. The dihedral angle between the bipyridyl planes is 38.31 (11)°. The distance from the centroid of one of the hydro­quinone mol­ecules to the center of the bipyridinium group is 3.653 (3) Å, which is within the range typically observed for molecular complexes exhibiting charge‐transfer characteristics.     

Packing effects in 4,4′‐bis(4‐hydroxy­butyl)‐2,2′‐bi­pyridine and 4,4′‐bis(4‐bromo­butyl)‐2,2′‐bi­pyridine

Structure analyses of 4,4′‐bis(4‐hydroxy­butyl)‐2,2′‐bi­pyridine, C₁₈H₂₄N₂O₂, (I), and 4,4′‐bis(4‐bromo­butyl)‐2,2′‐bi­pyridine, C₁₈H₂₂Br₂N₂, (II), reveal intermolecular hydrogen bonding in both compounds. For (I), O—H·N intermolecular hydrogen bonding leads to the formation of an infinite two‐dimensional polymer, and π stacking interactions are also observed. For (II), C—H·N intermolecular hydrogen bonding leads to the formation of a zigzag polymer. The two compounds crystallize in different crystal systems, but both mol­ecules possess C_i symmetry, with one half mol­ecule in the asymmetric unit.     

Tetra­allyl (2,2′‐bipyridyl)‐rac‐3,3,7,7‐tetra­methyl‐trans‐5‐palladatricyclo[4.1.0.02,4]­heptane‐1,2,4,6‐tetra­carboxyl­ate above and below the phase‐transition temperature of 194 K

The crystal structure of the title compound, (2,2′‐bipyridyl‐κ²N,N′)(tetra­allyl 3,3,3′,3′‐tetra­methyl‐1,1′‐bi­cyclo­propane‐1,1′,2,2′‐tetra­carboxyl­ato‐κ²C²,C^2′)­palladium(II), [Pd(C₂₆H₃₂­O₈)(C₁₀­H₈­N₂)], is disordered above 194 K. A doubling of the unit cell is observed on cooling. The structure at 143 K contains two ordered mol­ecules related by a pseudo‐translation vector of approximately (0.44,0.00,0.50) or a pseudo‐inversion center at approximately (0.22,0.00,0.25). Weak intermolecular C—H?O interactions are enhanced in the low‐temperature structure.     

Tetra­aqua(2,2′‐bi­pyridine)­nickel(II) terephthalate

The reaction of nickel(II) nitrate with terephthalic acid and 2,2′‐bi­pyridine in di­methyl­form­amide solution gives the title complex, [Ni(C₁₀H₈N₂)(H₂O)₄](C₈H₄O₄). The Ni^II ion is octahedrally coordinated to one 2,2′‐bi­pyridine and four water mol­ecules and does not coordinate to the terephthalate anion. Hydro­gen bonds between the terephthalate anions and the [Ni(2,2′‐bipy)(H₂O)₄]²⁺ cations produce a two‐dimensional hydrogen‐bonding architecture with double sheets.     

Di­aqua(2,2′‐bi­pyridine)­malonato­manganese(II)

In the crystal structure of the title compound, [Mn(C₃H₂O₄)(C₁₀H₈N₂)(H₂O)₂], the Mn^II atom demonstrates a distorted octahedral geometry, being coordinated by two N atoms of a 2,2′‐bi­pyridine ligand, two O atoms from the carboxyl­ate groups of the chelating malonate dianion and two O atoms of two cis water mol­ecules. The complex mol­ecules are linked to form a three‐dimensional supramolecular array by both hydrogen‐bonding interactions between coordinated water and the carboxyl­ate groups of neighboring mol­ecules and aromatic π–π‐stacking interactions of the bi­pyridine rings.     

(R)‐(+)‐2,2′‐Bis­(di­phenyl­phosphinoyl)‐1,1′‐bi­naphthyl

The title compound, BINAP oxide, C₄₄H₃₂O₂P₂, (I), was synthesized by direct oxidation of (R)‐(+)‐2,2′‐bis­(di­phenyl­phosphino)‐1,1′‐bi­naphthyl (BINAP) with tert‐butyl hydro­peroxide in toluene solution. The angle between the naphthyl planes of the bi­naphthyl group is 94.17 (3)°.     

N,N′‐Bis(2‐pyridylmeth­yl)ferrocene‐1,1′‐diyldicarboxamide and N,N′‐bis­(3‐pyridylmeth­yl)ferrocene‐1,1′‐diyldicarboxamide

The mol­ecules of N,N′‐bis­(2‐pyridylmeth­yl)ferrocene‐1,1′‐diyl­dicarboxamide, [Fe(C₁₂H₁₁N₂O)₂], contain intra­molecular N—H⋯N hydrogen bonds and are linked into sheets by three independent C—H⋯O hydrogen bonds. The mol­ecules of the isomeric compound N,N′‐bis­(3‐pyridylmeth­yl)ferrocene‐1,1′‐diyldicarboxamide lie across inversion centres, and the mol­ecules are linked into sheets by a combination of N—H⋯N hydrogen bonds and π–π stacking inter­actions between pyridyl groups.     

(2,2′‐Bi­pyridine‐κ2N,N′)(2,3‐naph­tha­lene­diolato‐κ2O,O′)­palladium(II) and (2,2′‐bi­quinoline‐κ2N,N′)(2,3‐naph­thal­ene­diolato‐κ2O,O′)­palladium(II)

In the title compounds, [Pd(C₁₀H₆O₂)(C₁₀H₈N₂)], (I), and [Pd(C₁₀H₆O₂)(C₁₈H₁₂N₂)], (II), each Pd^II atom has a similar distorted cis‐planar four‐coordination geometry involving two O atoms of the 2,3‐­naphthalenediolate dianion and two N atoms of the 2,2′‐bi­pyridine or 2,2′‐bi­quinoline ligand. The overall structure of (I) is essentially planar, but that of (II) is not, as a result of intramolecular overcrowding leading to bowing of the bi­quinoline ligand.     

A single‐strand helical coordination polymer: catena‐poly­[[[tri­aqua­nickel(II)]‐μ‐2,2′‐bi­pyridine‐3,3′‐di­carboxyl­ato‐κ3N,N′:O] monohydrate]

The asymmetric unit of the title compound, {[Ni(C₁₂H₆N₂O₄)(H₂O)₃]·H₂O}_n, is composed of a lattice water mol­ecule and a nickel(II) ion that is coordinated by three water mol­ecules and the two N atoms of a 2,2′‐bi­pyridine‐3,3′‐di­carboxyl­ate ligand. The twist of the 2,2′‐bi­pyridine‐3,3′‐di­carboxyl­ate unit and the coordination of one carboxyl­ate group to a symmetry‐related Ni^II atom generate a helical chain that runs along the b axis. Intrahelical hydrogen bonds participate in controlling the orientation of the helices, and both right‐handed and left‐handed helices are connected by interhelical hydrogen bonds into two‐dimensional sheets.     

Bis(3‐amino­pyridine‐κN)(4,4′‐di­methyl‐2,2′‐bipyridine‐κ2N,N′)(per­chlorato‐κO)copper(II) per­chlorate

The title compound, [Cu(ClO₄)(C₅H₆N₂)₂(C₁₂H₁₂N₂)]ClO₄, was prepared by in situ partial ligand substitution between 3‐amino­pyridine and 4,4′‐dimethyl‐2,2′‐bipyridine at room temperature. The central copper(II) ion is five‐coordinated by one bidentate 4,4′‐dimethyl‐2,2′‐bipyridine mol­ecule, two monodentate pyridine‐coordinated 3‐amino­pyridine mol­ecules and one apical O atom from the perchlorate counter‐ion. Inter­molecular N—H⋯O and C—H⋯O hydrogen‐bonding inter­actions form a hydrogen‐bond‐sustained network.     

4,4′‐Bis(N,N‐diethyl­amino)‐2,2′‐bi­pyridine

The title compound, C₁₈H₂₆N₄, contains two almost identical independent mol­ecules that lie about inversion centres. Each mol­ecule has a planar bi­pyridine nucleus and two terminal diethyl­amine groups oriented at almost right angles to the core. These diethyl­amine branches act as spacers, producing a very open structure with one of the lowest densities reported among related compounds. The most important intermolecular interactions are of the C—H⋯π type, which connect non‐equivalent moieties.     

fac‐Tri­carbonyl(4,4′‐di­methyl‐2,2′‐bi­pyridine)­tri­phenyl­tin(II)­rhenium(I)

The title organometallic compound, fac‐tri­carbonyl‐2κ³C‐(4,4′‐di­methyl‐2,2′‐bi­pyridine)‐2κ²N,N′‐tri­phenyl‐1κ³C¹‐tin(II)­rhenium(I)(Sn—Re), [ReSn(C₆H₅)₃(C₁₂H₁₂N₂)(CO)₃], con­tains three unique π–π stacking interactions. The result is an infinite chain of uninterrupted alternating intra‐ and intermolecular offset π–π stacking interactions throughout the crystal lattice. This extended π–π stacking arrangement, and an additional isolated intramolecular π–π interaction between the remaining 4,4′‐di­methyl‐2,2′‐bi­pyridine ring and a second phenyl group, impose geometric constraints on the Re and Sn atoms, yielding distorted octahedral and tetrahedral coordinations, respectively, for the metal centers.     

Hydrogen‐bonded one‐dimensional networks in 1:1 complexes of N,N′‐bis(2‐pyridyl)aryldiamines with anilic acid

The 1:1 complexes N,N′‐bis(2‐pyridyl)­benzene‐1,4‐di­amine–anilic acid (2,5‐di­hydroxy‐1,4‐benzo­quinone) (1/1), C₁₆H₁₄N₄·C₆H₄O₄, (I), and N,N′‐bis(2‐pyridyl)­bi­phenyl‐4,4′‐di­amine–anilic acid (1/1), C₂₂H₁₈N₄·C₆H₄O₄, (II), have been prepared and their solid‐state structures investigated. The component mol­ecules of these complexes are connected via conventional N—H?O and O—H?N hydrogen bonds, leading to the formation of an infinite one‐dimensional network generated by the cyclic motif R(9). The anilic acid molecules in both crystal structures lie around inversion centres and the observed bond lengths are typical for the neutral mol­ecule. Nevertheless, the pyridine C—N—C angles [120.9 (2) and 120.13 (17)° for complexes (I) and (II), respectively] point to a partial H‐atom transfer from anilic aicd to the bispyridyl­amine, and hence to H‐atom disorder in the OHN bridge. The bispyridyl­amine mol­ecules of (I) and (II) also lie around inversion centres and exhibit disorder of their central phenyl rings over two positions.     

(3R*,3′R*)‐1,1′‐Dimethyl‐3,3′‐biindoline‐2,2′‐dithione

The (3R*,3′R*) configuration of the title compound, C₁₈H₁₆N₂S₂, (I), has been unambiguously elucidated by X‐­ray analysis. Mol­ecules of (I) have C₂ symmetry to a good approximation and a strongly folded shape. The interplanar angle between the two halves of a mol­ecule is 67.11 (6)°.     

trans‐Di­aqua­bis(5‐carboxy‐1H‐imidazole‐4‐carboxyl­ato‐κ2N3,O4)­cobalt(II) 4,4′‐bi­pyridine solvate

In the title compound, [Co(C₅H₃N₂O₄)₂(H₂O)₂]·C₁₀H₈N₂, the Co atom is trans‐coordinated by two pairs of N and O atoms from two monoanionic 4,5‐di­carboxy­imidazole ligands, and by two O atoms from two coordinated water mol­ecules, in a distorted octahedral geometry. The 4,4′‐bi­pyridine solvent molecule is not involved in coordination but is linked by an N—H⋯N hydrogen bond to the neutral [Co(C₅H₃N₂O₄)₂(H₂O)₂] mol­ecule. Both mol­ecules are located on inversion centers. The crystal packing is stabilized by N—H⋯N and O—H⋯O hydrogen bonds, which produce a three‐dimensional hydrogen‐bonded network. Offset π–π stacking interactions between the pyridine rings of adjacent 4,4′‐bi­pyridine molecules were observed, with a face‐to‐face distance of 3.345 (1) Å.     

Mono­alkyl­ated 4′‐aryl‐substituted terpyridines

1‐Methyl‐2‐[4‐phenyl‐6‐(pyridinium‐2‐yl)­pyridin‐2‐yl]­pyridinium diperchlorate, C₂₂H₁₉N₃²⁺·2ClO₄⁻, (I), and 2‐[4‐(methoxy­phenyl)‐2,2′‐bipyridin‐6‐yl]‐1‐methyl­pyridinium iodide, C₂₃H₂₀N₃O⁺·I⁻, (II), both crystallize in the monoclinic space group P2₁/c. In contrast with the monocharged mol­ecule of (II), the doubly charged mol­ecule of (I) contains an additional protonated pyridine ring. One of the two perchlorate counter‐anions of (I) interacts with the cation of (I) via an N—H⋯O hydrogen bond. In (II), two mol­ecules related by a centre of symmetry are connected by weak π–π interactions, forming dimers in the crystal structure.     

{2,2′‐[1,1′‐(4‐Aza­heptane‐1,7‐diyl­dinitrilo)diethyl­idyne]­diphenolato}­copper(II)

The quinquedentate ligand 2,2′‐[1,1′‐(4‐aza­heptane‐1,7‐diyl­dinitrilo)diethyl­idyne]diphenol in the title compound, [Cu(C₂₂H₂₇N₃O₂)], furnishes an N₃O₂ donor set, which results in a distorted square‐pyramidal coordination; the two O and two imine N atoms lie in the basal plane, while the secondary amine N atom of the ligand occupies the axial position. The axial Cu—N bond is 0.33 Å longer than the average of the equatorial bonds, and the O atoms are trans. The symmetry of the mol­ecule is lowered by the twist–boat and chair conformations adopted by the two CuNN chelate rings. The complex contains two intra­molecular C—H⋯O inter­actions, and two mol­ecules of the complex are linked into a dimer by means of moderate N—H⋯O hydrogen bonds. Spectroscopic evidence supports the presence of hydrogen bonds.     

Three bis‐ortho‐diynyl­arenes (BODA)

The molecule of 3,3′,4,4′‐tetrakis­(phenyl­ethynyl)­bi­phenyl, C₄₄H₂₆, is approximately planar and is located on a crystallographic inversion center. Bis­[3,4‐bis­(phenyl­ethynyl)­phenyl] ether, C₄₄H₂₆O, has mol­ecules located on twofold symmetry axes, whereas the molecule of 2,2‐bis­[3,4‐bis­(phenyl­ethynyl)­phenyl]­propane, C₄₇H₃₂, does not exhibit any molecular symmetry.     

A series of three bis­[2‐(methyl/tri­fluoro­methyl)‐4H‐3,1‐benzoxazin‐4‐one] compounds

Each of the three title compounds, namely 6,6′‐methyl­ene­bis­(2‐methyl‐4H‐3,1‐benz­oxazin‐4‐one), C₁₉H₁₄N₂O₄, 6,6′‐methyl­ene­bis­(2‐tri­fluoro­methyl‐4H‐3,1‐benz­oxazin‐4‐one), C₁₉H₈F₃N₂O₄, and 6,6′‐bi­(2‐tri­fluoro­methyl‐4H‐3,1‐benz­oxazin‐4‐one), C₁₈H₆F₆N₂O₄, contains two planar benz­ox­azin­one fragments. In the first two compounds, these planes are virtually perpendicular to each other, while the third compound is planar overall. The electronic effects of the substituent groups on the oxazine moiety result in distortion of the bond angles at the C atoms of the C=O and C=N bonds, and in redistribution of electronic density in the oxazine rings. The latter leads to different bond lengths within this ring in the three mol­ecules. All the mol­ecules form stacks in their crystals with distances of 3.2–3.6 Å between adjacent mol­ecules in a stack.     

Triaqua(2,2′‐bipyridine‐κ2N,N′)(nitrato‐κO)manganese(II) nitrate

The crystal structure of the title compound, [Mn(NO₃)(C₁₀H₈N₂)(H₂O)₃]NO₃, contains a monomeric [Mn(NO₃)(bpy)(H₂O)₃]⁺ cation (bpy is 2,2′‐bi­pyridine) and a nitrate anion. The Mn^II ion is coordinated by one chelating bpy [Mn—N 2.241 (3) and 2.259 (3) Å], three water mol­ecules [Mn—O 2.120 (3)–2.188 (3) Å] and a nitrate ligand [Mn—O 2.228 (2) Å] in a distorted octahedral geometry. There are O?H—O hydrogen‐bonding interactions between the ligated water mol­ecules and the ligated and unligated nitrate anions, resulting in double columns of stacked cations and anions.