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As fascinating examples of closely connected multiple π-electronic systems involving noncovalent interactions, the cooperatively interlocked [2+1]-type anion complexes of well-designed π-electronic molecules are reported. The anion-responsive π-electronic molecules investigated in this study are the boron complexes of dipyrrolyldiketones bearing arylethynyl moieties at the pyrrole α-positions. Diverse substituents were introduced at the terminal aryl moieties, thus controlling the cooperativity to form [2+1]-type complexes. Theoretical studies showed that this cooperativity was induced by effective interactions between the introduced arylethynyl moieties. The investigations of the anion-binding processes showed that the first and second bindings to the guest anion were energetically almost equivalent, indicating the fundamental and important features of the electronic states of the halide anions. Furthermore, the interlocked anion complexes, whose geometries were distorted from the orthogonal arrangements, had the racemic states of the chiral conformations, either of which was induced by ion pairing with an appropriate chiral π-electronic cation, resulting in the chiroptical property as shown by circular dichroism. [ABSTRACT FROM AUTHOR]

Imidazolium- and benzimidazolium-substituted diacetylenes with bromide or nitrogen-rich dicyanamide and tricyanomethanide anions were synthesized and used as precursors for the preparation of N-doped carbon materials. On pyrolysis under argon at 800 °C both halide precursors afforded graphite-like structures with nitrogen contents of about 8.5 %. When the dicyanamide and tricyanomethanide precursors were thermolyzed at the same temperature, graphite-like structures were obtained that exhibit nitrogen contents in the range 17-20 wt %; thereby, the benefit of associating a polymerizing cation with a polymerizing anion in a single precursor was demonstrated. On pyrolysis at 1100 °C the nitrogen contents of the latter pyrolysates remain high (ca. 6 wt %). Adsorption measurements with krypton at 77 K indicated that the materials are nonporous. The highest electrical conductivity was observed for a pyrolysate with one of the lowest nitrogen contents, which also has the highest degree of graphitization. Thus, the quest for N-rich carbons with high electrical conductivities should include both maximization of the nitrogen content and optimization of the degree of graphitization. Crystallographic investigation of the precursors and spectroscopic characterization of the pyrolysates prepared by heating at 220 °C indicate that construction of the final carbon framework does not involve the intermediate formation of a polydiacetylene. [ABSTRACT FROM AUTHOR]

Abstract: Pentazolate anion (cyclo‐N5−), and/or N3−, NO3− were used as the ligands to obtain a series of nitrogen‐rich energetic three‐dimensional (3D) frameworks [Cu(N5)(N3)]n, [Ag(N5)]n, [Ba(N5)(NO3)(H2O)3]n, and [NaBa3(N5)6(NO3)(H2O)3]n by self‐assembly. These frameworks were characterized by single‐crystal X‐ray diffraction, SEM, IR and Raman spectroscopy, elemental analysis, and thermal analysis. All the frameworks exhibited regular supramolecular structures and excellent stabilities at room temperature which can be attributed to the strong coordination bonds between cyclo‐N5− anions and metal ions. The successful stabilization of the cyclo‐N5− in more 3D multi‐ligand metal‐N5− frameworks after Na‐N5− frameworks has been demonstrated. This breakthrough offers new opportunities for the future of metal‐pentazolate frameworks and polynitrogen chemistry. [ABSTRACT FROM AUTHOR]

Abstract: Visible‐light‐driven conversion of CO2 to CO and high‐value‐added carbon products is a promising strategy for mitigating CO2 emissions and reserving solar energy in chemical form. We report an efficient system for CO2 transformation to CO catalyzed by bare CoP, hybrid CoP/carbon nanotubes (CNTs), and CoP/reduced graphene oxide (rGO) in mixed aqueous solutions containing a Ru‐based photosensitizer, under visible‐light irradiation. The in situ prepared hybrid catalysts CoP/CNT and CoP/rGO show excellent catalytic activities in CO2 reduction to CO, with a catalytic rates of up to 39 510 and 47 330 μmol h−1 g−1 in the first 2 h of reaction, respectively; a high CO selectivity of 73.1 % for the former was achieved in parallel competing reactions in the photoreduction of CO2 and H2O. A combination of experimental and computational studies clearly shows that strong interactions between CoP and carbon‐supported materials and partially adsorbed H2O molecules on the catalyst surface significantly improve CO‐generating rates. [ABSTRACT FROM AUTHOR]

Abstract: Eleven‐vertex closo and nido boron clusters with one or two exo‐cyano groups were obtained by a series of consecutive cage‐opening and cage‐closure reactions starting from K2[closo‐B11H11] (K21). In the first step, K21 reacts with KCN in water at elevated temperatures to yield [7‐NC‐nido‐B11H12]2− (5 a). Oxidation of 5 a with PbO2 gives [NC‐closo‐B11H10]2− (2). In analogous subsequent reactions, dianion 2 was converted with KCN regioselectively to [7,9‐(NC)2‐nido‐B11H11]2− (6 a), which was further oxidized to [(NC)2‐closo‐B11H9]2− (3). The {nido‐B11} dianions 5 a and 6 a were protonated to yield [7‐NC‐nido‐B11H13]− (5 b) and [7,9‐(NC)2‐nido‐B11H12]− (6 b). All anions were studied by NMR spectroscopy and, except for 6 b, salts of all anions were characterized by IR and Raman spectroscopy and by elemental analysis. The position of the cyano group(s) in 5 a and 6 a were confirmed by NMR data and single‐crystal X‐ray diffraction studies on [Ph4P]25 a⋅CH2Cl2 and [Et4N]26 a. The {closo‐B11} clusters are fluxional in solution. In the crystal of [EMIm]22 the BCN vertex is in the 2‐position. Two isomers of dianion 3, [2,3‐(NC)2‐closo‐B11H9]2− and [2,6‐(NC)2‐closo‐B11H9]2−, were identified in the crystal of its [Et4N]+ salt. The peak oxidation potentials Epa of anions 1–3, 5 a, 6 a, 5 b, and [nido‐B11H14]− (4 b), determined by cyclic voltammetry, increase with increasing number of cyano groups. Increasing Epa in the order 1<2<3 parallels the increasing reactivity toward cyanide anions. [ABSTRACT FROM AUTHOR]

Abstract: Sulfonates were incorporated into six novel high‐nuclearity silver(I) thiolate clusters under the guidance of anion templates varied from S2−, SO42−, α‐[Mo5O18]6−, β‐[Mo5O18]6−, [Mo2O8]4−, to [Mo4O14(SO4)]6−. Single crystal X‐ray analysis revealed that SD/Ag1, SD/Ag3, SD/Ag5, and SD/Ag6 are discrete [S@Ag60], [α‐Mo5O18@Ag36], [Mo2O8@Ag30]2, and [Mo4O14(SO4)@Ag73] clusters, respectively, whereas SD/Ag2 and SD/Ag4 are one‐dimensional (1D) chains based on the [SO4@Ag20] and [β‐Mo5O18@Ag36] cluster subunits, respectively. Their silver skeletons are protected exteriorly by thiolates and sulfonates and interiorly supported by diverse anions as templates. Structurally, cluster SD/Ag1 is a typical core–shell structure comprised of an inner Ag12 cuboctahedron and an outer Ag48 shell. The sulfate‐templated drum‐like Ag20 cluster subunits are bridged by PhSO3− to give a 1D chain of SD/Ag2. Complex SD/Ag3 and SD/Ag4 are spindle‐like Ag36 clusters with isomeric [Mo5O18]6− inside, and the latter is further extended to a 1D chain through PhSO3− bridges. A pair of [Mo2O8]4− templated gourd‐like Ag30 clusters are dimerized in a head‐to‐head fashion to form SD/Ag5. Complex SD/Ag6 is the largest cluster in this family and doubly templated by unprecedented [Mo4O14(SO4)]6− anions. Geometrically, the silver shells of SD/Ag1–SD/Ag5 show the polyhedral features of Johnson solids, instead of the usual Platonic or Archimedean solids. Solution behaviors and luminescent properties were also investigated in detail. [ABSTRACT FROM AUTHOR]

ABSTRACT The kinetics of the reactions of benzylidenecyanoacetates 1a-d (X = H, Me, OMe, and NMe2) with nitroalkyl anions 2a-c have been studied in aqueous solution at 20°C. The second-order rate constants are used to evaluate the electrophilicity parameter E of these series of Michael acceptors 1a-d according to the linear free enthalpy relationship log k (20°C) = sN ( E + N). The measured E values were found to cover a domain of reactivity, ranging from −10.07 for the most reactive electrophile 1a (X = H) to −14.04 for the less electrophile 1d (X = NMe2). Mayr's approach was found to correctly predict the rate constants for the reactions of these series of olefins 1a-d with the hydroxide ion in water and 50% water-50% acetonitrile at 20°C. Analysis of the kinetic measurements using the Brönsted relationship shows that βnuc values remain remarkably constant for changes in the nature of the substituent X. A notable finding of this work is perhaps provided by the observed large changes in the electrophilicity parameter E on going from benzylidenecyanoacetates 1 to their analogues benzylidenemalonates 3 (Δ E ∼ 9.06-10.48), whereas the replacement of second CO2Et group by the CN group in 1 to give benzylidenemalononitriles 4 has little effect on electrophilic reactivity, i.e., Δ E ∼ 0.65-0.95. This abnormal pattern in the E values has been attributed to the resonance interaction and salvation effects. On the other hand, the effect of benzylidenecyanoacetate substituents on the electrophilic reactivity was examined quantitatively on the basis of the electrophilicity parameter E, leading to linear correlation of E with Hammett-Brown substituent constants ( [ABSTRACT FROM AUTHOR]

The electrochemical synthesis is an underestimated synthesis protocol, which can lead to unexpected results. We obtained an unusual CuI complex salt with a pentanuclear anion and a heptanuclear cation. The anion [Cu5(S tBu)6]- features a trigonal prism coordination motif with a twisted arrangement. The cation [Cu7(S tBu)6(bipy)3]+ is structurally almost identical to the anion and shares therefore basic building principles. These Cu-S skeletons with additional N donor functions in the cation have relevance to biological copper proteins. Besides structural discussion and analysis, a theoretical study was performed to determine stabilizing effects. This is accomplished by means of DFT with a triple-zeta basis set and the TPSSh functional in order to highlight bonding interactions and to understand d10-d10 interactions, which are assigned a major stabilizing part. This is realized through Wiberg bond analysis and frontier orbital analysis of both ions. [ABSTRACT FROM AUTHOR]

Protonation of trans-1,2-bis(4-pyridyl)ethylene (4,4′-bpe) with dilute sulfuric acid (33 %) afforded a protonated adduct [{4,4′-bpe⋅2 H+}2{HSO4}−2{SO4}−2{H2O}2] ( 1). The neighboring olefinic bond in 1 is in a suitable range (3.931-4.064 Å) to undergo a photochemical [2+2] cycloaddition reaction. Upon irradiation with UV light (365 nm), 1 undergoes a molecular sliding involving the 4,4′-bpe⋅2 H+ units, affording 2, stabilized through OSO4⋅⋅⋅π interactions. Heating 1 to 50° C leads to a 3D hydrogen-bonded organic framework (HOF) ( 3). This process occurs through thermal dissociation of the bisulfate anion. Diffusion of iodine through the crystal lattice of 1 and 3 enables the reduction of sulfate to bisulfate, affording a 1D hydrogen-bonded chain ( 4). Solid-state 13C CPMAS NMR, IR, DSC, and powder XRD studies further support stimuli-responsive structural tuning through crystal-to-crystal transformation. All these conversions occur with significant translational and rotational movements along with a series of bond-breaking and bond-forming processes. [ABSTRACT FROM AUTHOR]

CH stretches in hydrocarbon cations often shift to lower frequencies relative to neutral molecules, because they do not have sufficient electrons to give every bond an electron pair. A parallel effect in negatively charged species has not been previously observed. Here we show that CH bond weakening occurs in alkoxide anions as a consequence of hyperconjugation. The reasoning differs somewhat from the case of positively charged ions, but the net effect is the same: to lower CH stretching frequencies by hundreds of wavenumbers. [ABSTRACT FROM AUTHOR]

Anion-π catalysis, that is the stabilization of anionic transition states on π-acidic aromatic surfaces, has so far been developed with naphthalenediimides (NDIs). This report introduces perylenediimides (PDIs) to anion-π catalysis. The quadrupole moment of PDIs (+23.2 B) is found to exceed that of NDIs and reach new records with acceptors in the core (+70.9 B), and their larger surface provides space to better accommodate chemical transformations. Unlike NDIs, the activity of PDI catalysts for enolate and enamine addition is determined by the twist of their π surface rather than their reducibility. These results, further strengthened by nitrate inhibition and circular dichroism spectroscopy, support an understanding of anion-π interactions centered around quadrupole moments, i.e., electrostatic contributions, rather than redox potentials and charge transfer. The large PDI surfaces provide access to the highest enantioselectivities observed so far in anion-π catalysis (96 % ee). [ABSTRACT FROM AUTHOR]

Anion binding properties of neutral helical foldamers consisting of urea type units in their backbone have been investigated. 1H NMR titration studies in various organic solvents including DMSO suggest that the interaction between aliphatic oligoureas and anions (CH3COO−, H2PO4−, Cl−) is site-specific, as it largely involves the urea NHs located at the terminal end of the helix (positive pole of the helix), which do not participate to the helical intramolecular hydrogen-bonding network. This mode of binding parallels that found in proteins in which anion-binding sites are frequently found at the N-terminus of an α-helix. 1H NMR studies suggest that the helix of oligoureas remains largely folded upon anion binding, even in the presence of a large excess of the anion. This study points to potentially useful applications of oligourea helices for the selective recognition of small guest molecules. [ABSTRACT FROM AUTHOR]

The title anion was synthesized by heating dimethylformamide (DMF) solution of the known Ni-centered and Ni(CO)-capped tin clusters [Ni@Sn9Ni(CO)]3−. The new anion represents the first example of face-fused nine-atom molecular clusters. The two clusters are identical elongated tricapped trigonal prisms of nido-[Sn8Ni(CO)]6− with nickel at one of the capping positions. They are fused along a triangular face adjacent to a trigonal prismatic base and made of two Sn and one Ni atoms. The new anion is structurally characterized by single-crystal X-ray diffraction in the compound (K[222-crypt])4[Sn14Ni(CO)]⋅DMF. Its presence in solution is corroborated by electrospray mass spectrometry. [ABSTRACT FROM AUTHOR]

The iron selenidoantimonate(III) [Fe(phen)3]Sb6Se10 ( 1) (phen = 1, 10-phenanthroline) was prepared by reaction of Fe, Sb, Se, phen, and 1, 4-diazabicyclo[2.2.2]octane in MeOH and H2O mixed solvent under solvothermal conditions. 1 consists of a [Fe(phen)3]2+ cation and a two dimensional [Sb6Se10]2- anion. The [Sb6Se10]2- anion is constructed by SbSe3, SbSe4, and SbSe6 primary building blocks by corner- and edge-sharing, resulting Sb4Se4, Sb5Se5, and Sb6Se6 heterorings and a semi-cubic Sb4Se6 motif, which act as secondary building units. The octahedral SbSe6 primary unit and semi-cubic Sb4Se6 motif make compound 1 quite different from the thioantimonates(III). Compound 1 exhibits steep bandgap ( Eg) of 1.56 eV, indicating potential semiconducting property. The thermal stability of 1 was also investigated. [ABSTRACT FROM AUTHOR]

The title anion was synthesized by heating dimethylformamide (DMF) solution of the known Ni-centered and Ni(CO)-capped tin clusters [Ni@Sn9Ni(CO)]3−. The new anion represents the first example of face-fused nine-atom molecular clusters. The two clusters are identical elongated tricapped trigonal prisms of nido-[Sn8Ni(CO)]6− with nickel at one of the capping positions. They are fused along a triangular face adjacent to a trigonal prismatic base and made of two Sn and one Ni atoms. The new anion is structurally characterized by single-crystal X-ray diffraction in the compound (K[222-crypt])4[Sn14Ni(CO)]⋅DMF. Its presence in solution is corroborated by electrospray mass spectrometry. [ABSTRACT FROM AUTHOR]

Complexes [(C4Me4)Co(CO)2{Co(P2C2 tBu2)2}] ( 1, C4Me4 = tetramethylcyclobutadiene) and [CpNi{Co(P2C2 tBu2)2}(PPh3)] ( 2, Cp = cyclopentadienyl) were synthesized by transmetalating [Tl(thf)2{Co(P2C2 tBu2)2}] with [(C4Me4)Co(CO)2I] and [CpNiBr(PPh3)]. Compounds 1 and 2 were fully characterized by X-ray crystallography, multinuclear NMR, UV/Vis, and IR spectroscopy, and elemental analysis. Their molecular structures show σ-coordination of one phosphorus atom of the [Co(P2C2 tBu2)2]- anion to the second metal atom (cobalt or nickel). Time-dependent density functional theory (TD-DFT) calculations were applied to gain insight into the electronic structures and the nature of the electronic transitions observed in the UV/Vis spectra. Cyclic voltammetry studies revealed the similar redox behavior of 1 and 2, which are reversibly oxidized to the corresponding monocations 1+ and 2+ with retention of the dinuclear structures. The cyclic voltammograms furthermore show that 1 and 2 decompose upon reduction with cleavage of the dinuclear structures into the free [Co(P2C2 tBu2)2]- anion and further uncharacterized products. [ABSTRACT FROM AUTHOR]

The radical anion of cyclopentasilane-fused hexasilabenzvalene was synthesized by the reduction of the corresponding neutral compound. X-ray crystallographic analysis showed a more trans-bent structure of the disilene moiety than the neutral compound. Theoretical calculations showed that the highly trans-bent structure is attributed to the hexasilabenzvalene structure. The EPR spectrum showed that an unpaired electron exists mainly at the disilene moiety. In the UV/Vis spectrum, a large bathochromic shift was observed compared with the neutral compound. [ABSTRACT FROM AUTHOR]

Anions [B12Cl11NH3]- and [B12Cl11OH]2- were prepared in high yields from the known precursors [B12H11NH3]- and [B12H11OH]2- by using SO2Cl2. Reaction monitoring by 11B NMR spectroscopy and ESI-mass spectrometry indicated that SO2Cl2 serves as a convenient chlorination reagent in both transformations. This chemical is an alternative to SbCl5 or chlorine gas, which have been used in reported procedures. [B12Cl11NMe3]- was prepared in 92 % overall yield from [B12H11NH3]- salts without isolation of the unmethylated intermediate. Starting from [B12Cl11OH]2-, [B12Cl11OS(O)CF3]2- was obtained unexpectedly by using Tf2O in pyridine/CH2Cl2 by a rare reduction process, while [B12Cl11OTs]2- was synthesized by using TsCl in pyridine. All compounds were fully characterized by NMR and IR spectroscopy and ESI-mass spectrometry. [Ag(MeCN)4][B12Cl11NH3], [Et4N][B12Cl11NH3], [Me4N]2[B12Cl11OH], [Et3NH][Cs][B12Cl11OH], [Ph3PMe]2[B12Cl11OS(O)CF3], and [MePPh3]2[B12Cl11OTs] were studied by X-ray diffraction. [ABSTRACT FROM AUTHOR]

A new family of bipodal anion transporters based on chalcogen-containing scaffolds has been designed and synthesized. Though structurally related to the well-studied tripodal anionophores, these molecules are simpler with only two anion-binding sites. However, the activities remain high. Anion transport could be facilitated by the new transporter at an exceptionally low loading of transporter/lipid ratio of 1:500000. This impressive efficiency is comparable with the most active one from the tren-based tripodal series. To investigate influences from different scaffolds and substituent groups, lipophilicity, anion-binding property, and transport activity of each molecule were studied. It was found that the bridge atom has a major impact on transport activities mainly as a result of anion-binding differences. The results also suggest that chalcogen can act as a key structural modulator to develop highly effective anion transporters and optimize their activities. [ABSTRACT FROM AUTHOR]

Dodecaborate anions of the type B12X122− and B12X11Y2− (X=H, Cl, Br, I and Y=OH, SH, NH3+, NR3+) form strong (Ka up to 106 L mol−1, for B12Br122−) inclusion complexes with γ-cyclodextrin (γ-CD). The micromolar affinities reached are the highest known for this native CD. The complexation exhibits highly negative enthalpies (up to −25 kcal mol−1) and entropies (TΔS up to −18.4 kcal mol−1, both for B12I122−), which position these guests at the bottom end of the well-known enthalpy-entropy correlation for CDs. The high driving force can be traced back to a chaotropic effect, according to which chaotropic anions have an intrinsic affinity to hydrophobic cavities in aqueous solution. In line with this argument, salting-in effects revealed dodecaborates as superchaotropic dianions. [ABSTRACT FROM AUTHOR]

By following a new synthetic approach, which is based on the in situ formation of a basic medium by the reaction between the strong base Sb(V)S43- and the weak acid H2O, it was possible to prepare three layered thioantimonate(III) compounds of composition [TM(2,2'-bipyridine)3][Sb6S10] (TM=Ni, Fe) and [Ni(4,4'-dimethyl-2,2'- bipyridine)3][Sb6S10] under hydrothermal conditions featuring two different thioantimonate(III) network topologies. The antimony source, Na3SbS4 ∙ 9H2O, undergoes several decomposition reactions and produces the SbIIIS3 species, which condenses to generate the layered anion. The application of transition-metal complexes avoids crystallization of dense phases. The reactions are very fast compared to conventional hydrothermal/solvothermal syntheses and are much less sensitive to changes of the reaction parameters. [ABSTRACT FROM AUTHOR]

The reaction constant ( ρ) from the kinetics for hydride transfer from a carbanion (XH-) to 9-arylxanthylium ions (9-GPhXn+) in CH3CN was unusually negative. Thermodynamic analysis indicated that ρ for the simple hydride transfers (only involved with release and capture of a hydride anion) should be positive; this is in contrast to the kinetics results. Consequently, this reaction is not a simple hydride transfer. An 'intermediate' was also found in the reaction system, the formation of which resulted in the unusual ρ. [ABSTRACT FROM AUTHOR]

Compounds containing both B-O and P-O groups are of wide interest and have been classified into borophosphates and borate-phosphates by R. Kniep et al. In addition to the B/P ratio, analysis results show that regulating the [M/(B+P)] ratio is also an effective strategy to synthesize new borate-phosphates. The first lithium lead borate-phosphate, LiPb4(BO3)(PO4)2, was synthesized by regulating this ratio. This compound crystallizes in the orthorhombic space group Pbca (No. 61). It possesses a 3D structure with a corrugated 2D layer of [B2Pb8O18]∞ that is further connected by a [LiP2O8]∞ chain; both BO3 and PO4 were isolated. First-principle theoretical studies were performed to aid the understanding of the electronic structures and the linear optical properties. In addition, thermal analysis, IR spectroscopy, and UV/Vis/NIR diffuse reflectance spectroscopy were performed on the reported material. [ABSTRACT FROM AUTHOR]

Azaborolyl anions, the five-membered BN heterocycles, have attracted a considerable attention due to their aromaticity and isoelectronic relationship with ubiquitous cyclopentadienyl ligands. Besides their syntheses and applications in the preparation of metal complexes, the other aspects of their chemistry have been virtually unexplored. Reduction of the azabutadienyl chelate boron dichloride [ArNC(R)CHC(R)]BCl2 ( 2, Ar=2,6-Me2C6H3, R= tBu) with two equivalents of potassium yielded the novel 2-chloro-azaborolyl anion [ArNC(R)CHC(R)BCl]K(thf) ( 3) as a stable product in good yield. Reaction of 3 with 1,3,4,5-tetramethylimidazol-2-ylidene (NHC) yielded the first NHC-azaborole adduct with the elimination of KCl. The salt elimination reaction was also observed in the reactions with H2O and the organic azide ArN3, leading to the formation of an oxo-bridged 3 H-1,2-diazaborole and an intramolecular donor-stabilized iminoborane, demonstrating that 3 is a source of the unexplored 1,2-azaborole isosteric to cyclopentadienylidene. [ABSTRACT FROM AUTHOR]

The new dithiophosphate anion P2S6(OEt)22- was obtained from the reaction of commercially available P4S10 with Na2S in pyridine, subsequent ethanolysis and isolated as the stable bis(pyridinium) salt 1. The molecular structure of 1 in the crystal was determined by single-crystal X-ray diffraction and reveals a PSSP dihedral angle of 87.3(1)° within the anion. The compound is a rare representative of a thiodiphosphate anion with a disulfide bridge between the two phosphorus atoms. [ABSTRACT FROM AUTHOR]

The cyano-rich borate anion [B(tceg)2]- (tceg = tetracyanoethylene glycolate) has been synthesized in a two-step reaction from Na[B(OMe)4] with two equivalents of the cyanohydrin analogue Me3SiOC2(CN)4OSiMe3. The structures of the starting materials, an isolated intermediate Na2[B2(OMe)2(tceg)3], and Na[B(tceg)2] are discussed. Thermal studies of WCC[B(tceg)2] [WCC = 1-ethyl-3-methylimidazolium (EMIm), 1-butyl-3-methylimidazolium (BMIm), 1-octyl-3-methylimidazolium (OMIm), Me4N, Et4N, and Bu4N], synthesized by salt metathesis, showed that the compounds with EMIm, BMIm, OMIm, and Bu4N have ionic liquid properties. The synthesis, structure, and analytical results of Me3SiOC(CN)3 are discussed as well as the results of its conversion with Na[B(OMe)4]. [ABSTRACT FROM AUTHOR]

The host-guest complex [(DIPA)([18]crown-6)](ClO4) ( 1; DIPA=2,6-diisopropylanilinium) was constructed and found to undergo a sequence of phase transitions ( Ibam- Pbcn- Pna21) at T1=278 K and T2=132 K, respectively. Systematic characterizations, such as differential scanning calorimetry, heat capacity, temperature-dependent dielectric constant, and P-E hysteresis loop, reveal that the centrosymmetric-to-polar phase transition at T2 is a paraelectric-to-ferroelectric transition. The symmetry breaking was also confirmed by temperature-dependent second-harmonic generation effect and X-ray powder diffraction. The ferroelectric mechanism is attributable to the linear motion of the perchlorate counterions accompanied by the order-disorder transition of the [18]crown-6 molecules and the anions. [ABSTRACT FROM AUTHOR]

A diuranium(V) arene complex reductively cleaves P4 to give a triuranium heptaphosphanortricyclane cluster (see picture; U green, P purple, N blue, Si orange). This cluster is the first example of a molecular actinide [P7] Zintl complex and the first example of uranium‐promoted catenation of P4. This complex undergoes a wide range of reactions under mild conditions to afford liberated P7R3 phosphanortricyclanes. [ABSTRACT FROM AUTHOR]

The article presents a research that studies the syntheses and characterization of binary selenium azide compounds. It discusses methodologies used in the research including selenium-based nuclear magnetic resonance (Se NMR) spectroscopy, Raman spectroscopy, and density functional analysis. It concludes that neutral binary selenium azide is thermally unstable and explosive, while its anions with large inert counter ions are more manageable.

Two new materials of the composition ({CH3(CH2)15(CH3)2S}+)2[CoBr4]2- ( 1) and ({CH3(CH2)15(CH3)2S}+)2[CuBr4]2- ( 2 and 3), of which the latter exists in two polymorphs, were synthesized. The materials display the synthetically targeted structures, comprising of layers of complex metal ions and layers of long-chain sulfonium cations. The crystal structures of the materials were determined. The interlayer distances are around 24 Å, with metal-metal distances about 8 Å. The magnetic properties of 1 were investigated, and the material is paramagnetic. ({CH3(CH2)15(CH3)2S}+)2[CuBr4]2 is polymorphic. Both polymorphs crystallize with triclinic symmetry. [ABSTRACT FROM AUTHOR]

N, N-Bis(1 H-tetrazol-5-yl)amine anions (HBTA-/BTA2-) were used as suitable nitrogen-rich components for the construction of energetic ionic liquids. Seven ionic liquids, namely, 1,3-dimethylimidazolium ( 1, [C1mim]HBTA), 1-ethyl-3-methylimidazolium ( 2, [C2mim]HBTA), 1-butyl-3-methylimidazolium ( 3, [C4mim]HBTA), 1-hexyl-3-methylimidazolium ( 4, [C6mim]HBTA), 1-methyl-3-octylimidazolium ( 5, [C8mim]HBTA), and 1,2,3-trimethylimidazolium ( 6, [C1mmim]HBTA) cations with the HBTA- anion and di-1,2,3-trimethylimidazolium N, N-bis(1 H-tetrazol-5-yl)amine ( 7, [C1mmim]2BTA), were synthesized. All materials were fully characterized by IR and NMR spectroscopy, elemental analysis, and high-resolution mass spectrometry. The crystal structures of 1 and 7 were determined by single-crystal X-ray diffraction [ 1: monoclinic, P21/ n, a = 14.0653(4) Å, b = 6.9507(2) Å, c = 22.4699(7) Å, β = 93.996(3)°, V = 2191.38(12) Å3, Z = 8, ρ = 1.511 g cm-3; 7: monoclinic, P21/ c, a = 17.5869(3) Å, b = 12.8757(2) Å, c = 21.9203(6) Å, β = 125.0580(10)°, V = 4063.15(15) Å3, Z = 8, ρ = 1.221 g cm-3]. The nitrogen contents of 1- 7 exceed 40 %, and 1 has the highest value of 61.78 %. The ionic liquids 1- 7 are thermally stable to 220 °C, and 2- 5 are room-temperature ionic liquids. The heats of formation of 1- 7 obtained by both experimental and theoretical methods are all positive. The ionic liquids 1- 7 are insensitive towards impact (>40 J) and friction (>360 N). They can be ignited in air. These new energetic ionic liquids contain only C, H, and N and are of interest as potential propellants with high energy, high thermal stability, low sensitivity to impact and friction, and environmentally friendly decomposition gases. [ABSTRACT FROM AUTHOR]

The article discusses the synthesis and cycloaddition of 2-phosphaethynolate anion. It says that 2-phosphaethynolate anion is believed to be accessed by nucleophilic attacks and reactive to unsaturated substrates. It also mentions several 2-phosphaethynolate anion reactions such as metal-mediated dimerization and oxidative tetramerization.

Novel lanthanide selenidostannate polymers containing the soft-base Sn2Se6 ligand, (H3O) n[La(tepa)(μ-1κ2:2κ2-Sn2Se6)] n ( 1), [{Nd(tepa)(μ-OH)}2(μ-1κ:2κ-Sn2Se6)] n ( 2), and [{Gd(tepa)(μ-OH)}2(μ-1κ:2κ-Sn2Se6)] n · nH2O ( 3) (tepa = tetraethylenepentamine) were prepared by treating lanthanide oxides with Sn and Se using pentadentate polyamine tepa as a second ligand under solvothermal conditions. In 1, the La3+ ion is coordinated by a tepa ligand to form an unsaturated [La(tepa)]3+ unit, and the [Sn2Se6]4- anion acts as a tetradentate bridging ligand with four terminal Se atoms to connect the [La(tepa)]3+ units into a coordination polymeric anion [La(tepa)(μ-1κ2:2κ2-Sn2Se6)-] n. The μ-1κ2 Se1, Se2:2κ2 Se5, Se6 bridging mode in 1 is a new coordination mode for the Sn2Se6 unit to LnIII centers. In 2 and 3, the lanthanide ion is coordinated by a tepa ligand, and two [Ln(tepa)]3+ (Ln = Nd, Gd) ions are joined by two μ-OH bridges to form dinuclear cations. Behaving as a bidentate μ-Sn2Se6 ligand with the trans-terminal Se atoms, the Sn2Se6 units connect the [{Ln(tepa)(μ-OH)}2]4+ cations into neutral coordination polymers [{Ln(tepa)(μ-OH)}2(μ-Sn2Se6)] n. The coordination modes μ-1κ2 Se1, Se2:2κ2 Se5, Se6 in 1 and μ-1κ Se1:2κ Se5 in 2 and 3 are related to the metal size of the lanthanide(III) ions. In addition, as an ethylenepolyamine with higher denticity, the pentadentate tepa exhibits a significantly different influence on the structures of the solvothermally synthesized Ln selenidostannates compared to the bidentate ethylenediamine and tridentate diethylenetriamine. Compounds 1- 3 are semiconductors with well-defined band gaps of 1.95-2.34 eV. [ABSTRACT FROM AUTHOR]