Crystal structure of bis-(1,3-di-amino-propane-κ(2) N,N')bis-[2-(4-nitro-phen-yl)acetato-κO]cadmium.

In the structure of the title compound, [Cd(C8H6NO4)2(C3H10N2)2], the Cd(II) atom is located on a center of symmetry with one independent Cd-O distance of 2.3547 (17) Šand two Cd-N distances of 2.3265 (18) and 2.3449 (19) Å. The Cd(II) atom has an overall octa-hedral coordination environment. Several types of hydrogen-bonding inter-actions are evident. Both intra- and inter-molecular inter-actions occur between the amino groups and the O atoms of the acetate group. These N-H⋯O hydrogen bonds lead to a layered structure extending parallel to the bc plane. In addition, weak inter-molecular C-H⋯O inter-actions involving the nitro groups exist, leading to the formation of a three-dimensional network structure.

Crystal structure of tert-butyl-diphenyl-phosphine oxide.

In the structure of the title triorganophosphine oxide, C16H19OP, the P-O bond is 1.490 (1) Å. The P atom has a distorted tetrahedral geometry. The O atom inter-acts with both phenyl groups of a neighboring mol-ecule [C⋯O = 2.930 (3) and 2.928 (4) Å]. The C-O interaction directs an extended supramolecular arrangement along the a-axis.

Crystal structure of a methimazole-based ionic liquid.

The structure of 1-methyl-2-(prop-2-en-1-ylsulfan-yl)-1H-imidazol-3-ium bromide, C7H11N2S(+)·Br(-), has monoclinic (P21/c) symmetry. In the crystal, the components are linked by N-H⋯Br and C-H⋯Br hydrogen bonds. The crystal structure of the title compound undeniably proves that methimazole reacts through the thione tautomer, rather than the thiol tautomer in this system.

Crystal structure of tri-phenyl(vinyl)-phospho-nium tetra-phenyl-borate.

The title ionic salt, C21H20P(+)·C24H20B(-), crystallized with two independent vinyl-tri-phenyl-phospho-nium cations and two independent tetra-phenyl-borate anions per asymmetric unit. These four independent moieties contain nearly perfect tetra-hedral symmetry about their respective central C atoms. In the crystal, there are no π-stacking or other inter-molecular inter-actions present.

Crystal structure of catena-poly[[aqua(2,2':6',2''-terpyridine-κ(3) N,N',N'')cobalt(II)]-µ-cyanido-κ(2) N:C-[dicyanidoplatinum(II)]-µ-cyanido-κ(2) C:N].

The title compound, [Co(C15H11N3)(H2O){Pt(CN)4}] n , is a one-dimensional coordination polymer formed under hydro-thermal reaction conditions. The Co(II) site has sixfold coordination with a distorted octa-hedral geometry, while the Pt(II) ion is coordinated by four cyanide groups in an almost regular square-planar geometry. The compound contains twofold rotation symmetry about its Co(II) ion, the water molecule and the terpyridine ligand, and the Pt(II) atom resides on an inversion center. trans-Bridging by the tetra-cyanidoplatinate(II) anions links the Co(II) cations, forming chains parallel to [-101]. Additionally, each Co(II) atom is coordin-ated by one water mol-ecule and one tridentate 2,2':6',2''-terpyridine ligand. O-H⋯N hydrogen-bonding inter-actions are found between adjacent chains and help to consolidate the crystal packing. In addition, relatively weak π-π stacking inter-actions exist between the terpyridine ligands of adjacent chains [inter-planar distance = 3.464 (7) Å]. No Pt⋯Pt inter-actions are observed in the structure.

Crystal structure of di-µ-benzato-κ(4) O:O'-bis-[aqua-(benzato-κO)(benzato-κ(2) O,O')(2,2':6',2''-terpyridine-κ(3) N,N',N'')europium(III)]-benzoic acid (1/2).

The title compound, [Eu2(C7H5O2)6(C15H11N3)2(H2O)2]·2C7H6O2, is a co-crystalline compound containing a dinuclear Eu(III) coordination complex with inversion symmetry co-crystallized with benzoic acid in a 1:2 ratio. The Eu(3+) ions within the dimer are nine-coordinate, containing one tridentate terpyridine, one water, and four benzoate ions, two of which bridge the Eu(3+) ions. Of the four benzoate ligands coordinating to each Eu(3+) position, three distinct coordination modes [monodentate, bidentate-chelating, and bidentate-bridging (twice)] are observed. Within the crystal, there are two additional uncoordinating benzoic acid mol-ecules per dinuclear complex. Within the dimer, the water bound to each Eu(3+) ion participates in intra-molecular hydrogen bonding with a coordinating benzoate. Additionally, the carb-oxy-lic acid group on the benzoic acid participates in inter-molecular hydrogen bonding with a benzoate ligand bound to the dimer complex.

On the formation of a protic ionic liquid in nature.

The practical utility of ionic liquids (ILs) makes the absence (heretofore) of reported examples from nature quite puzzling, given the facility with which nature produces many other types of exotic but utilitarian substances. In that vein, we report here the identification and characterization of a naturally occurring protic IL. It can be formed during confrontations between the ants S. invicta and N. fulva. After being sprayed with alkaloid-based S. invicta venom, N. fulva detoxifies by grooming with its own venom, formic acid. The mixture is a viscous liquid manifestly different from either of the constituents. Further, we find that the change results as a consequence of formic acid protonation of the N centers of the S. invicta venom alkaloids. The resulting mixed-cation ammonium formate milieu has properties consistent with its classification as a protic IL.

Crystal structure of bis-(2,2':6',2''-terpyridine-κ(3) N,N',N'')nickel(II) dicyanidoaurate(I).

The title compound, [Ni(C15H11N3)2][Au(CN)2]2, is an ionic compound composed of bis-(2,2':6',2''-terpyridine)-nickel(II) dications and dicyanidoaurate(I) anions in a 1:2 ratio. The two tridentate terpyridine ligands define the coordination of the Ni(2+) cation, resulting in a nearly octa-hedral coordination sphere, although there is not any imposed crystallographic symmetry about the Ni(2+) site. The two nearly linear dicyanidoaurate(I) anions [C-Au-C = 179.0 (2) and 178.2 (2)°] contain a short aurophilic inter-action of 3.1017 (3) Å. The structure does not demonstrate any π-π stacking. Non-classical C-H⋯N inter-actions between the cations and anions build up a three-dimensional network.

Emission, Raman spectroscopy, and structural characterization of actinide tetracyanometallates.

Three new compounds, {U2(H2O)10(O)[Pt(CN)4]3}·4H2O, {Th2(H2O)10(OH)2[Pd(CN)4]3}·8H2O, and {(UO2)2(DMSO)4(OH)2[Ni(CN)4]}, in the actinide tetracyanometallate, Anx[M(CN)4]y, class of compounds have been synthesized and characterized by confocal Raman spectroscopy and single crystal X-ray diffraction. These compounds contain unique structures illustrating dimeric actinide species. The absence of intense charge transfer emission in the visible range for {U2(H2O)10(O)[Pt(CN)4]3}·4H2O, as compared to the platinum starting material, is unusual because of the presence of pseudo-one-dimensional Pt···Pt chains in this compound. Confocal Raman spectroscopy of the cyanide stretching region provides insight into the binding domain (mono-, bi-, tri-, tetradentate) of the tetracyanometallates in these novel structures.

A co-crystal of 1,10-phenanthroline with boric acid: a novel aza-aromatic complex.

The title compound, C12H8N2·2B(OH)3, is best described as a host-guest complex in which the B(OH)3 mol-ecules form a hydrogen-bonded cyclic network of layers parallel to the ab plane into which the 1,10-phenanthroline mol-ecules are bound. An extensive network of hydrogen bonds are responsible for the crystal stability. No π-stacking inter-actions occur between the 1,10-phenanthroline mol-ecules.

{2,6-Bis[(2,6-diisopropyl-phosphan-yl)-oxy]-4-fluoro-phenyl-κ(3)P,C(1),P'}(1H-pyrazole-κN(2))nickel(II) hexa-fluoro-phosphate.

The title compound, [Ni(C(18)H(30)FO(2)P(2))(C(3)H(4)N(2))]PF(6), was prepared by halide abstraction with TlPF(6) in the presence of CH(3)CN in CDCl(3) from the respective neutral pincer chlorido analogue followed by addition of pyrazole. The PO-C-OP pincer ligand acts in typical trans-P(2) tridentate fashion to generate a distorted square-planar nickel structure. The Ni-N(pyrazole) distance is 1.925 (2) Šand the plane of the pyrazole ligand is rotated 56.2 (1)° relative to the approximate square plane surrounding the Ni(II) center in which the pyrazole is bound to the Ni(II) atom through its sp(2)-hybridized N atom. This Ni-N distance is similar to bond lengths in the other reported Ni(II) pincer-ligand square-planar pyrazole complex structures; however, its dihedral angle is significantly larger than any of those for the latter set of pyrazole complexes.

Synthesis, crystal structures, and dual donor luminescence sensitization in novel terbium tetracyanoplatinates.

A series of novel terbium tetracyanoplatinate compounds all incorporating tridentate 2,2':6'2″-terpyridine (terpy) or 4'-chloro-2,2':6'2″-terpyridine (terpy-Cl) were synthesized and used to investigate the phenomenon of dual-donor sensitization of Tb(3+). Judicious choice of the Tb(3+) salt and reaction conditions results in the isolation of {Tb(terpy)(H2O)2(NO3)Pt(CN)4}·CH3CN (1A), {Tb(terpy)(H2O)2(NO3)Pt(CN)4}·3.5H2O (1B), {Tb(terpy-Cl)(H2O)2(NO3)Pt(CN)4}·2.5H2O (2), [Tb(terpy)(H2O)2(CH3COO)2]2Pt(CN)4·4H2O (3), or [Tb2(terpy)2(H2O)2(CH3COO)5]2Pt(CN)4·7H2O (4). The compounds 1A, 1B, and 2 contain one-dimensional polymeric structures with bridging of [Tb(L)(NO3)(H2O)2](2+) (L = terpy or terpy-Cl) moieties by cis-bridging tetracyanoplatinate (TCP) anions as determined via single-crystal X-ray diffraction studies. Both 3 and 4, however, contain Tb(3+) coordinated by multiple acetate ligands and terpy, but not TCP, and are classified as zero-dimensional complex salts. Platinophilic interactions that dominate tetracyanoplatinate structural chemistry are present in the form of dimeric units in the polymeric compounds, but are totally absent in 3 and 4. The structural differences result in markedly different luminescence properties for the two classes of compounds. All of the polymeric compounds display efficient donor-acceptor intramolecular energy transfer (IET) from the terpy unit to the Tb(3+) ion. Although the TCP units are also directly coordinated to the Tb(3+) ion in the three polymers, only in 1B and 2 are the Pt···Pt interactions strong enough to provide MMLCT bands of appropriate energy to result in a dual-donor effect to the Tb(3+) sensitization. Even in these cases, TCP does not efficiently sensitize the Tb(3+), rather a broad band TCP emission results. However, terpy and acetate ligands are bonded directly to the Tb(3+) ion in 3 and 4 and provide a strong dual-donor sensitization effect as evidenced by the large QY for Tb(3+).

Synthesis, structural, and photoluminescence studies of Gd(terpy)(H2O)(NO3)2M(CN)2 (M = Au, Ag) complexes: multiple emissions from intra- and intermolecular excimers and exciplexes.

The highly luminescent bimetallic cyanide materials, Gd(terpy)(H(2)O)(NO(3))(2)M(CN)(2) (M = Au, Ag; GdAu and GdAg, respectively) are quick and easy to synthesize under ambient conditions. A characteristic feature exhibited by both solid-state compounds is an intense red emission when excited with UV light. Additionally, GdAu exhibits a broad-band green emission upon excitation in the near UV region. A combination of structural and spectroscopic results for the compounds helps explain the underlying conditions responsible for their unique properties. Single-crystal X-ray diffraction experiments expose their structural features, including the fact that they are isostructural. Crystallographic data for the representative GdAu compound (Mo K(α), λ = 0.71073 Å, T = 290 K): triclinic, space group P ̅1, a = 7.5707(3) Å, b = 10.0671(4) Å, c = 15.1260(4) Å, α = 74.923(3)°, ß = 78.151(3)°, γ = 88.401(3)°, V = 1089.04(7) Å(3), and Z = 2. Although the compounds crystallize as dimers containing M···M distances smaller than the sum of their van der Waals radii, the Au···Au (3.5054(4) Å) and/or the Ag···Ag (3.6553(5) Å) interactions are relatively weak and are not responsible for the low energy red emission. Rather, the green emission in GdAu presumably originates from the [Au(CN)(2)(-)](2) dimeric excimer, while the [Ag(CN)(2)(-)](2) dimers in GdAg do not display visible emission at either 290 or 77 K. The unusual red emission exhibited by both compounds likely originates from the formation of an excited state exciplex that involves intermolecular π-stacking of 2,2':6',2"-terpyridine ligands. The room-temperature and low-temperature steady-state photoluminescent properties, along with detailed time-dependent, lifetime, and quantum yield spectroscopic data provide evidence regarding the sources of the multiple visible emissions exhibited by these complexes.

Tris(thio-cyanato-κN)tris-(triphenyl-phosphine oxide-κO)europium(III)-(nitrato-κ(2) O,O')bis-(thio-cyanato-κN)tris-(triphenyl-phosphine oxide-κO)europium(III) (1/1).

The title co-crystal, [Eu(NCS)3(C18H15OP)3][Eu(NCS)2(NO3)(C18H15OP)3], contains two distinct neutral complexes. Each complex has threefold symmetry about its central Eu(3+) ion. As a result, the nitrate-containing mol-ecule contains disorder of its bidentate nitrate and two N-bound thio-cyanate anions, while the [Eu(NCS)3(OPPh3)3] complex is fully ordered. There is a weak π-π stacking inter-action between the phenyl rings of the two mol-ecules [centroid-centroid distance = 4.138 (4) Å].

Tris(thio-cyanato-κN)tris-(triphenyl-phosphine oxide-κO)terbium(III).

The title compound, [Tb(NCS)3(C18H15OP)3], contains a six-coordinate Tb(II) cation surrounded by three O-bound triphenyl-phosphine oxide ligands and three N-bound thio-cyanate ligands, each in a fac arrangement. There are two crystallographically unique Tb(III) atoms in the asymmetric unit. One Tb(III) atom resides on a threefold rotation axis, while the other has no imposed crystallographic symmetry. The thio-cyanate ligands are bound through N atoms, illustrating the hard-hard bonding principles of metal complex chemistry.

(1S*,2R*,3S*,4R*,5R*)-5-Tetra-decyloxy-methyl-7-oxabicyclo-[2.2.1]heptane-2,3-dicarb-oxy-lic anhydride.

In the title compound, C23H38O5, the oxabicyclo-[2.2.1]heptane-2,3-dicarb-oxy-lic anhydride unit has a normal geometry and the tetra-decoxymethyl side chain is fully extended. In the crystal, mol-ecules are linked head-to-head by C-H⋯O hydrogen bonds, forming two-dimensional networks propagating along the a and c-axis directions.

A new building block for electroactive organic materials? Synthesis, cyclic voltammetry, single crystal X-ray structure, and DFT treatment of a unique boron-based viologen.

A boronium-based paraquat analog undergoes reductions at more negative potentials than paraquat itself, making it a promising building block for electroactive materials.

2,6-Dichloro-1-[(1E)-2-(phenyl-sulfon-yl)ethen-yl]benzene.

In the title compound, C(14)H(10)Cl(2)O(2)S, the product of a base-catalyzed condensation followed by deca-rboxylation of the carboxyl-ate group of the sulfonyl derivative, the configuration of the alkene unit is E. The torsion angle between the alkene unit and the 2,6-dichloro-phenyl ring system is -40.8 (3)°. The dihedral angle between the rings is 80.39 (7)°.

{2,6-Bis[(2,6-diphenyl-phosphan-yl)-oxy]-4-fluoro-phenyl-κP,C,P'}(6-methyl-2,2,4-trioxo-3,4-dihydro-1,2,3-oxathia-zin-3-ido-κN)palladium(II).

The title acesulfamate complex, [Pd(C(30)H(22)FO(2)P(2))(C(4)H(4)NO(4)S)], contains a four-coordinate Pd(II) ion with the expected, although relatively distorted, square-planar geometry where the four L-Pd-L angles range from 79.58 (8) to 102.47 (7)°. The acesulfamate ligand is N-bound to Pd [Pd-N = 2.127 (2) Å] with a dihedral angle of 76.35 (6)° relative to the square plane. Relatively long phen-yl-acesulfamate C-H⋯O and phen-yl-fluorine C-H⋯F inter-actions consolidate the crystal packing.

Solid-state photoluminescence sensitization of Tb3+ by novel Au2Pt2 and Au2Pt4 cyanide clusters.

The syntheses are reported for two novel Tb(3+) heterotrimetallic cyanometallates, K(2)[Tb(H(2)O)(4)(Pt(CN)(4))(2)]Au(CN)(2)·2H(2)O (1) and [Tb(C(10)N(2)H(8))(H(2)O)(4)(Pt(CN)(4))(Au(CN)(2))]·1.5C(10)N(2)H(8)·2H(2)O (2) (C(10)N(2)H(8) = 2,2'-bipyridine). Both compounds have been isolated as colorless crystals, and single-crystal X-ray diffraction has been used to investigate their structural features. Crystallographic data (MoKα, λ = 0.71073 Å, T = 290 K): 1, tetragonal, space group P4(2)/nnm, a = 11.9706(2) Å, c = 17.8224(3) Å, V = 2553.85(7) Å(3), Z = 4; 2, triclinic, space group P1, a = 10.0646(2) Å, b = 10.7649(2) Å, c = 17.6655(3) Å, α = 101.410(2)°, ß = 92.067(2)°, γ = 91.196(2)°, V = 1874.14(6) Å(3), Z = 2. For the case of 1, the structure contains Au(2)Pt(4) hexameric noble metal clusters, while 2 includes Au(2)Pt(2) tetrameric clusters. The clusters are alike in that they contain Au-Au and Au-Pt, but not Pt-Pt, metallophilic interactions. Also, the discrete clusters are directly coordinated to Tb(3+) and sensitize its emission in both solid-state compounds, 1 and 2. The Photoluminescence (PL) spectra of 1 show broad excitation bands corresponding to donor groups when monitored at the Tb(3+) ion f-f transitions, which is typical of donor/acceptor energy transfer (ET) behavior in the system. The compound also displays a broad emission band at ∼445 nm, assignable to a donor metal centered (MC) emission of the Au(2)Pt(4) clusters. The PL properties of 2 show a similar Tb(3+) emission in the visible region and a lack of donor-based emission at room temperature; however, at 77 K a weak, broad emission occurs at 400 nm, indicative of uncoordinated 2,2'-bipyridine, along with strong Tb(3+) transitions. The absolute quantum yield (QY) for the Tb(3+) emission ((5)D(4) → (7)F(J (J = 6-3))) in 1 is 16.3% with a lifetime of 616 µs when excited at 325 nm. In contrast the weak MC emission at 445 nm has a quantum yield of 0.9% with a significantly shorter lifetime of 0.61 µs. For 2 the QY value decreases to 9.3% with a slightly shorter lifetime of 562 µs. The reduced QY in 2 is considered to be a consequence of (1) the slightly increased donor-acceptor excited energy gap relative to the optimal gap suggested for Tb(3+) and (2) Tb(3+) emission quenching via a bpy ligand-to-metal charge transfer (LMCT) excited state.