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A new solid-state material, N-butyl pyridinium diiodido argentate(I), is synthesized using a simple and effective one-pot approach. In the solid state, the compound exhibits 1D ([AgI2](-))(n) chains that are stabilized by the N-butyl pyridinium cation. The 1D structure is further manifested by the formation of long, needle-like crystals, as revealed from electron microscopy. As the general composition is derived from metal halide-based ionic liquids, the compound has a low melting point of 100-101 degrees C, as confirmed by differential scanning calorimetry. Most importantly, the compound has a conductivity of 10(-6) S cm(-1) at room temperature. At higher temperatures the conductivity increases and reaches to 10(-4 )S cm(-1) at 70 degrees C. In contrast to AgI, however, the current material has a highly anisotropic 1D arrangement of the ionic domains. This provides direct and tuneable access to fast and anisotropic ionic conduction. The material is thus a significant step forward beyond current ion conductors and a highly promising prototype for the rational design of highly conductive ionic solid-state conductors for battery or solar cell applications.
The synthesis and the crystal structure of the double cluster compound [Nb6Cl14(MeCN)(4)][Nb6Cl14(pyz)(4)]middot6CH(3)CN are described. The synthesis is based on a partial ligand exchange reaction, which proceeds upon dissolving [Nb6Cl14(pyz)(4)]middot2CH(2)Cl(2) in acetonitrile. The compound is built up of two discrete neutral cluster units, which consist of octahedra of Nb-6 atoms coordinated by 12 edge-bridging chlorido and two terminal chlorido ligands, and four acetonitrile ligands on one and four pyrazine ligands on the other cluster unit. Co-crystallized acetonitrile molecules are also present. The single-crystal structure determination has revealed a cluster arrangement in which the [Nb6Cl14(pyz)(4)] units are connected by (halogen) lone-pair-(pyrazine) pi interactions. These lead to chains of [Nb6Cl14(pyz)(4)] clusters. These chains are further connected to cluster layers by (nitrile-halogen) dipole-dipole interactions, in which the [Nb6Cl14(MeCN)(4)] and co-crystallized MeCN molecules are also involved. These cluster layers are arranged parallel to the crystallographic {011} plane.
A new solid-state material, N-butyl pyridinium diiodido argentate(I), is synthesized using a simple and effective one-pot approach. In the solid state, the compound exhibits 1D ([AgI2](-))(n) chains that are stabilized by the N-butyl pyridinium cation. The 1D structure is further manifested by the formation of long, needle-like crystals, as revealed from electron microscopy. As the general composition is derived from metal halide-based ionic liquids, the compound has a low melting point of 100-101 degrees C, as confirmed by differential scanning calorimetry. Most importantly, the compound has a conductivity of 10(-6) S cm(-1) at room temperature. At higher temperatures the conductivity increases and reaches to 10(-4 )S cm(-1) at 70 degrees C. In contrast to AgI, however, the current material has a highly anisotropic 1D arrangement of the ionic domains. This provides direct and tuneable access to fast and anisotropic ionic conduction. The material is thus a significant step forward beyond current ion conductors and a highly promising prototype for the rational design of highly conductive ionic solid-state conductors for battery or solar cell applications.
FicucariconeD (1) and its 4 '-demethyl congener 2 are isoflavones isolated from fruits of Ficus carica that share a 5,7-dimethoxy-6-prenyl-substituted A-ring. Both naturalproducts were, for the first time, obtained by chemical synthesisin six steps, starting from 2,4,6-trihydroxyacetophenone. Key stepsare a microwave-promoted tandem sequence of Claisen- and Cope-rearrangementsto install the 6-prenyl substituent and a Suzuki-Miyaura crosscoupling for installing the B-ring. By using various boronic acids,non-natural analogues become conveniently available. All compoundswere tested for cytotoxicity against drug-sensitive and drug-resistanthuman leukemia cell lines, but were found to be inactive. The compoundswere also tested for antimicrobial activities against a panel of eightGram-negative and two Gram-positive bacterial strains. Addition ofthe efflux pump inhibitor phenylalanine-arginine-beta-naphthylamide(PA beta N) significantly improved the antibiotic activity in mostcases, with MIC values as low as 2.5 mu M and activity improvementfactors as high as 128-fold.
The molecular structures of three closely related isoflavones have been determined by single crystal X-ray diffraction and have been analysed by geometry matching with the CSD, Hirshfeld surface analysis and analysis of stacking interactions with the Aromatic Analyser program (CSD). The formation of the supramolecular structure by non-covalent interactions was studied and substantial differences in the macroscopic properties e.g., the solubility, were correlated with hydrogen bonding and pi-stacking interactions. Moreover, a correlation between the supramolecular structure, the torsion angle (between benzopyran group and aryl group), and macroscopic properties was determined in the three compounds.
An efficient method for the preparation of arylnaphthalene lignans (ANLs) was developed, which is based on thePhoto-Dehydro-DIELS-ALDER(PDDA) reaction. While intermolecular PDDA reactions turned out to be inefficient, theintramolecular variant using suberic acid as tether linking two aryl propiolic esters smoothly provided naphthalenophanes. Theirradiations were performed with a previously developed annular continuous-flow reactor and UVB lamps. In this way, the naturalproducts Alashinol D, Taiwanin C, and an unnamed ANL could be prepared.
The compound [Nb6Cl14(pyrazine)(4)]center dot 2CH(2)Cl(2) (1) was investigated for its suitability as a starting compound for new ligand-supported hexanuclear niobium cluster compounds. The synthesis, stability to air and increased temperature, solubility and usability for subsequent reactions of 1, and purification and separation of the reaction products are discussed. The compounds with cluster units [Nb6Cl14L4], where L = iso-quinoline N-oxides (2), 1,1-dimethylethylenediamines (3), or thiazoles (4), and [Nb6Cl14(PEt3)(3.76)(Et3PO)(0.24)]-[Nb6Cl14(MeCN)(4)]center dot 4MeCN (5) are presented as follow-up products. The crystal structures of compounds 1-5 are analyzed, and the structures are discussed with respect to their intraand intermolecular bonding situations and crystal packing. In addition to hydrogen bonds and pi-pi interactions, the appearance of chalcogen and halogen bonds and lone pair-pi interactions between Nb-6 cluster units was observed for the first time.
Eight d-metal-containing N-butylpyridinium ionic liquids (ILs) with the nominal composition (C4Py)2[Ni0.5M0.5Cl4] or (C4Py)2[Zn0.5M0.5Cl4] (M = Cu, Co, Mn, Ni, Zn; C4Py = N-butylpyridinium) were synthesized, characterized, and investigated for their optical properties. Single crystal and powder X-ray analysis shows that the compounds are isostructural to existing examples based on other d-metal ions. Inductively coupled plasma optical emission spectroscopy measurements confirm that the metal/metal ratio is around 50 : 50. UV-Vis spectroscopy shows that the optical absorption can be tuned by selection of the constituent metals. Moreover, the compounds can act as an optical sensor for the detection of gases such as ammonia as demonstrated via a simple prototype setup.
Eight d-metal-containing N-butylpyridinium ionic liquids (ILs) with the nominal composition (C4Py)2[Ni0.5M0.5Cl4] or (C4Py)2[Zn0.5M0.5Cl4] (M = Cu, Co, Mn, Ni, Zn; C4Py = N-butylpyridinium) were synthesized, characterized, and investigated for their optical properties. Single crystal and powder X-ray analysis shows that the compounds are isostructural to existing examples based on other d-metal ions. Inductively coupled plasma optical emission spectroscopy measurements confirm that the metal/metal ratio is around 50 : 50. UV-Vis spectroscopy shows that the optical absorption can be tuned by selection of the constituent metals. Moreover, the compounds can act as an optical sensor for the detection of gases such as ammonia as demonstrated via a simple prototype setup.
Fifteen N-butylpyridinium salts - five monometallic [C4Py](2)[MBr4] and ten bimetallic [C4Py](2)[(M0.5M0.5Br4)-M-a-Br-b] (M=Co, Cu, Mn, Ni, Zn) - were synthesized, and their structures and thermal and electrochemical properties were studied. All the compounds are ionic liquids (ILs) with melting points between 64 and 101 degrees C. Powder and single-crystal X-ray diffraction show that all ILs are isostructural. The electrochemical stability windows of the ILs are between 2 and 3 V. The conductivities at room temperature are between 10(-5) and 10(-6) S cm(-1). At elevated temperatures, the conductivities reach up to 10(-4) S cm(-1) at 70 degrees C. The structures and properties of the current bromide-based ILs were also compared with those of previous examples using chloride ligands, which illustrated differences and similarities between the two groups of ILs.