262 research outputs found
(Acetonitrile-κN)[2-(diphenylphosphanyl)ethanamine-κ2 N,P][(1,2,3,4,5-η)-1,2,3,4,5-pentamethylcyclopentadienyl]iron(II) hexafluoridophosphate tetrahydrofuran monosolvate
In the title cationic Cp*Fe(II) complex, [Fe(C10H15)(CH3CN)(C14H16NP)]PF6·C4H8O, the metal ion is coordinated by the η
5-Cp* ring as well as the P and N atoms of the chelating 2-(diphenylphosphino)ethylamine ligand and an additional acetonitrile molecule in a piano-chair conformation. The PF6
− anion is disordered over two sets of sites with occupancies of 0.779 (7) and 0.221 (7)
2-{2-[3-(1H-Benzimidazol-2-yl)quinolin-2-yloxy]ethoxy}ethanol
In the title compound, C20H19N3O3, the interplanar angle between the benzimidazole unit and the quinoline unit is 25.1 (2)°. Two different hydrogen bonds involving the hydroxy group and the imidazole unit are present. An intramolecular N—H⋯O hydrogen bond links the hydroxy group of the side chain with the imidazole unit, forming a 12-membered ring, and an intermolecular O—H⋯N hydrogen bond links the molecules, forming chains in the crystallographic b direction
3-(1H-Benzimidazol-2-yl)-2-chloro-8-methylquinoline
Two independent molecules of the title compound, C17H12ClN3, are present in the structure. The angle between the planes defined by the atoms of the benzimidazole unit and the quinoline unit are 45.2 (3) and 44.0 (3)°, indicating an essentially identical conformation for both molecules. Each of the independent molecules is linked with a symmetry equivalent by an intermolecular N—H⋯N hydrogen bond involving the two benzimidazole N atoms, to form chains in the crystallographic c direction
Di-μ-chlorido-bis{[μ-1,8-bis(diisopropylphosphanyl)-9,10-dihydro-9,10-ethanoanthracene-κ2 P:P′]-μ-chlorido-μ-methylidene-dipalladium(II)} tetrahydrofuran pentasolvate
The title compound, [Pd4(CH2)2Cl4(C28H40P2)2]·5C4H8O, possesses a tetranuclear palladium core with four bridging chlorido ligands and two bridging methylene units, as well as two bridging anthracene-based bis-phosphine ligands. This tetranuclear complex can be considered as being composed of two μ-chlorido-bridged LPd2 units. The structural motif of these LPd2 units shows two doubly bridged palladium centers between the P atoms of the bis-phosphine ligand. One of these bridges is a μ-Cl atom, the other a μ-methylene group. The coordination environment around each palladium center is essentially square planar. We ascribe the oxidation state +II to the palladium centers and do not assume Pd—Pd bonds [shortest distances 2.8110 (5) and 2.8109 (6) Å]. Co-crystallized with the palladium complex we found five non-coordinating tetrahydrofuran solvent molecules, one of which is disordered over two positions in a 0.429 (9):0.571 (8) ratio
Di‐ and Tetracyano‐Substituted Pyrene‐Fused Pyrazaacenes: Aggregation in the Solid State
Means to stream: Five di- and tetracyano-substituted pyrene-fused pyrazaacenes were synthesized and studied as potential electron acceptors in the solid state. Single crystals of all compounds were grown, and the crystal packing was studied by XRD and DFT calculations of transfer integrals and reorganization energies with a view to their possible use as n-type semiconductors.
Five di- and tetracyano-substituted pyrene-fused pyrazaacenes were synthesized and studied as potential electron acceptors in the solid state. Single crystals of all compounds were grown and the crystal packing studied by DFT calculations (transfer integrals and reorganization energies) to get insight into possible use for semiconducting charge transport
μ3-Oxido-tris{dichlorido[1,3-bis(1,3,5-trimethylphenyl)imidazol-2-ylidene]gold(III)} bis(trifluoromethanesulfonyl)imide–[bis(trifluoromethanesulfonyl)imide]silver(I) (1/2)
The unusual trinuclear AuIII oxide title complex, [Au3Cl6O(C21H24N2)3](C2F6NO4S2)·2[Ag(C2F6NO4S2)], is the side product of the reaction of [1,3-bis(1,3,5-trimethylphenyl)imidazol-2-ylidene]dichloridophenylgold(III) with silver bis(trifluoromethanesulfonyl)imide in the presence of traces of water. In contrast to corresponding AuI complexes, the core structure of the title compound is planar. Two silver(I) bis(trifluoromethanesulfonyl)imide units are loosely bound to the complex cation. Here the silver atoms, disordered over two positions in a 0.870 (2):0.130 (2) ratio, interact either with the lone pairs of three chlorine ligands or two chlorine ligands and one edge of the mesityl π-system. The crystal under investigation was a partial racemic twin
Host‐Guest Chemistry of Truncated Tetrahedral Imine Cages with Ammonium Ions
Three shape-persistent [4+4] imine cages with truncated tetrahedral geometry with different window sizes were studied as hosts for the encapsulation of tetra-n-alkylammonium salts of various bulkiness. In various solvents the cages behave differently. For instance, in dichloromethane the cage with smallest window size takes up NEtt but not NMet, which is in contrast to the two cages with larger windows hosting both ions. To find out the reason for this, kinetic experiments were carried out to determine the velocity of uptake but also to deduce the activation barriers for these processes. To support the experimental results, calculations for the guest uptakes have been performed by molecular mechanics’ simulations. Finally, the complexation of pharmaceutical interested compounds, such as acetylcholine, muscarine or denatonium have been determined by NMR experiments
Quinoxalinophenanthrophenazine Based Cruciforms
Quinoxalinophenanthrophenazines (QPPs) and related structures are an emerging class of stable fused N-heteropolycyclic aromatics. By vertical attachment of aromatic substituents at the pyrene core, cruciform QPPs are accessible, which open new opportunities to adjust HOMO and LUMO levels of the QPPs nearly independent from each other.
A series of cruciform aryl-substituted quinoxalinophenanthrophenazine derivatives (QPPs) was synthesized through Suzuki-Miyaura cross-coupling of a 2,7-diborylated pyrene tetraketal building block. The QPPs were analyzed for their optoelectronic properties by absorption and emission spectroscopy, cyclic voltammetry and quantum-chemical calculations. The solid-state packing was investigated as well and evaluated for its charge transport properties by calculated charge transfer integrals
Chlorido[3,3′-dibutyl-5,5′-(pyridine-2,6-diyl)dipyrazol-1-ido]gold(III)
The Au atom in the C2-symmetric pincer-type title complex, [AuCl(C19H23N5)], is in the +3 oxidation state. The ligand is composed of one pyridine unit and two n-butyl-substituted pyrazoles (pyrz). Both pyrazoles are deprotonated, thus forming a neutral compound. To the best of our knowledge, this is the first AuIII–bispyrazolate complex. According to the special geometry in the N,N′,N′′-tridentate ligand, containing two five-membered heterocycles, the complex deviates from an ideal square-planar coordination geometry; the Npyrz—Au—Npyrz angle is 160.8 (3)°, indicating a distortion of nearly 20°
Efficient Synthesis of Dipyrrolobenzenes and Dipyrrolopyrazines via Bidirectional Gold Catalysis:a Combined Synthetic and Photophysical Study
New N-heterocyclic fluorophores are sought-after compounds for organic electronic devices. Here, we report on a straightforward synthesis to access meta/para-dipyrrolobenzenes and para-dipyrrolopyrazines in high yields using a bidirectional gold-catalyzed cyclization strategy. The versatility of our reaction protocol was showcased by preparing dipyrroloarenes with different substituents, various functional groups, and in a multitude of substitution patterns. Furthermore, we showed that the dipyrroloarenes can be post-modified by N-alkylation to improve the solubility or bromination to yield precursors for further derivatization via cross-coupling. Investigation of the photophysical properties of the-mostly unprecedented-dipyrroloarenes identified strong blue emitters such as the diphenyl meta-dipyrrolobenzene with a quantum yield of 98%. Moreover, we showed that changes in the solvent polarity or interactions with Lewis acids such as borane can be used to fine-tune the photophysical properties of the fluorophores.</p
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