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The chemical bonding of Zintl clusters is still an evolving and hot topic in modern chemistry. In this paper we synthesized a novel [K([2.2.2]crypt)]4[In8Bi13] complex in a condensed phase. The quantum chemical calculations and X‐ray data revealed that the compound consists of the 1:1 mixture of [Bi@In8Bi12]3− and [Bi@In8Bi12]5− clusters. To the date, those clusters are the largest binary clusters composed of In and Bi elements. Herein, we introduce a spherical aromatic description of chemical bonding for such clusters. We show through AdNDP, ELF, and induced magnetic field and quantitative NICS analyzes that both clusters are spherically aromatic which explains their high symmetry, stability, and peculiar magnetic properties. We believe that this work will help researchers in the further development and understanding of chemical bonding in Zintl clusters. [ABSTRACT FROM AUTHOR]

In an effort to combine the favorable catalytic properties of Co3O4 and CeO2, nanocomposites with different phase distribution and Co3O4 loading were prepared and employed for CO oxidation. Synthesizing Co3O4‐modified CeO2 via three different sol‐gel based routes, each with 10.4 wt % Co3O4 loading, yielded three different nanocomposite morphologies: CeO2‐supported Co3O4 layers, intermixed oxides, and homogeneously dispersed Co. The reactivity of the resulting surface oxygen species towards CO were examined by temperature programmed reduction (CO‐TPR) and flow reactor kinetic tests. The first morphology exhibited the best performance due to its active Co3O4 surface layer, reducing the light‐off temperature of CeO2 by about 200 °C. In contrast, intermixed oxides and Co‐doped CeO2 suffered from lower dispersion and organic residues, respectively. The performance of Co3O4‐CeO2 nanocomposites was optimized by varying the Co3O4 loading, characterized by X‐ray diffraction (XRD) and N2 sorption (BET). The 16–65 wt % Co3O4−CeO2 catalysts approached the conversion of 1 wt % Pt/CeO2, rendering them interesting candidates for low‐temperature CO oxidation. [ABSTRACT FROM AUTHOR]

In this work, a simple, fast and dry method for the fabrication of a thermochromic product with a high load of VO2(M1) consisting of the controlled heat treatment of pure vanadium nanoparticles in air is presented. After a complete design of experiments, it is concluded that the most direct way to attain the maximum transformation of V into VO2(M1) consists of one cycle with a fast heating ramp of 42 °C s−1, followed by keeping 700 °C for 530–600 seconds, and a subsequent cooling at 0.05 °C s−1. Careful examination of these results lead to a second optimum, even more suitable for industrial production (quicker and less energy‐intensive because of its lower temperatures and shorter times), consisting of subjecting V to two consecutive cycles of temperatures and times (625 °C for 5 minutes) with similar preheating (42 °C s−1) but a much faster postcooling (∼ 8 °C s−1). These green reactions only use the power for heating a tube open to atmosphere and a vanadium precursor; without assistance of reactive gases or catalysts, and no special vacuum or pressure requirements. The best products present similar thermochromic properties but higher thermal stability than commercial VO2 particles. These methods can be combined with VO2 doping. [ABSTRACT FROM AUTHOR]

Non-innocent ligands render the determination of the electronic structure in metal complexes difficult. As such, a combination of experimental techniques and quantum chemistry are required to correctly elucidate them. This paper deals with the one-electron oxidation of copper(II) and nickel(II) complexes featuring a phosphasalen ligand (Psalen), which differs from salen analogues by the presence of iminophosphorane groups (P=N) instead of imines. Various experimental techniques (X-ray diffraction, cyclic voltammetry, NMR, EPR, and UV/Vis spectroscopies, and magnetic measurements) as well as quantum chemical calculations were used to define the electronic structure of the oxidized complexes. These can be modified by a small change in the ligand structure, that is, the replacement of a tert-butyl group by a methoxy on the phenoxide ring. The different techniques have allowed quantifying the amount of spin density located on the metal center and on the Psalen ligands. All complexes were found to possess a multi-configurational ground state, in which the ratio of the +II versus +III oxidation state of the metal center, and therefore the phenolate versus phenoxyl radical ligand character, varies upon the substituents. The tert-butyl group favors a strong localization on the metal center whereas with the methoxy group the metallic configurations decrease and the ligand configurations increase. The importance of the geometrical considerations compared with the electronic substituent effect is highlighted by the differences observed between the solid-state (EPR, magnetic measurements) and solution characterizations (EPR and NMR data). [ABSTRACT FROM AUTHOR]

N‐heterocyclic carbene ligands (NHC) are widely utilized in catalysis and material science. They are characterized by their steric and electronic properties. Steric properties are usually quantified on the basis of their static structure, which can be determined by X‐ray diffraction. The electronic properties are estimated in the liquid state; for example, via the 77Se liquid state NMR of Se‐NHC adducts. We demonstrate that 77Se NMR crystallography can contribute to the characterization of the structural and electronic properties of NHC in solid and liquid states. Selected Se‐NHC adducts are investigated via 77Se solid state NMR and X‐ray crystallography, supported by quantum chemical calculations. This investigation reveals a correlation between the molecular structure of adducts and NMR parameters, including not only isotropic chemical shifts but also the other chemical shift tensor components. Afterwards, the liquid state 77Se NMR data is presented and interpreted in terms of the quantum chemistry modelling. The discrepancy between the structural and electronic properties, and in particular the π‐accepting abilities of adducts in the solid and liquid states is discussed. Finally, the 13C isotropic chemical shift from the liquid state NMR and the 13C tensor components are also discussed, and compared with their 77Se counterparts. 77Se NMR crystallography can deliver valuable information about NHC ligands, and together with liquid state 77Se NMR can provide an in‐depth outlook on the properties of NHC ligands. [ABSTRACT FROM AUTHOR]

In a joint effort utilizing modified sample preparation, microscopy, X‐ray diffraction and micro‐fabrication, it became possible to prepare single crystals of the "hidden" phase AlCr2. High‐resolution X‐ray diffraction analysis is described in detail for two crystals with the similar overall composition, but different degree of disorder, which seems to be the main cause for the differing unit cell parameters. Chemical bonding analysis of AlCr2 in comparison to prototypical MoSi2 shows pronounced differences reflecting the interchange of main group element vs. transition metal as majority component. [ABSTRACT FROM AUTHOR]

In recent years, the reactivity of gold complexes was shown to extend well beyond π‐activation and to hold promises to achieve selective cross‐couplings in several C−C and C−E (E=heteroatom) bond forming reactions. Here, with the aim of exploiting new organometallic species for cross‐coupling reactions, we report on the Au(III)‐mediated C(sp2)−C(sp) occurring upon reaction of the cyclometalated complex [Au(CCH2N)Cl2] (1, CCH2N=2‐benzylpyridine) with AgPhCC. The reaction progress has been monitored by NMR spectroscopy, demonstrating the involvement of a number of key intermediates, whose structures have been unambiguously ascertained through 1D and 2D NMR analyses (1H, 13C, 1H‐1H COSY, 1H‐13C HSQC and 1H‐13C HMBC) as well as by HR‐ESI‐MS and X‐ray diffraction studies. Furthermore, crystallographic studies have serendipitously resulted in the authentication of zwitterionic Au(I) complexes as side‐products arising from cyclization of the coupling product in the coordination sphere of gold. The experimental work has been paralleled and complemented by DFT calculations of the reaction profiles, providing valuable insight into the structure and energetics of the key intermediates and transition states, as well as on the coordination sphere of gold along the whole process. Of note, the broader scope of the cross‐coupling at the Au(III) CCH2N centre has also been demonstrated studying the reaction of 1 with C(sp2)‐based nucleophiles, namely vinyl and heteroaryl tin and zinc reagents. These reactions stand as rare examples of C(sp2)−C(sp2) cross‐couplings at Au(III). [ABSTRACT FROM AUTHOR]

Molybdenum alkylidyne complexes with a trisilanolate podand ligand framework ("canopy catalysts") are the arguably most selective catalysts for alkyne metathesis known to date. Among them, complex 1 a endowed with a fence of lateral methyl substituents on the silicon linkers is the most reactive, although fairly high loadings are required in certain applications. It is now shown that this catalyst decomposes readily via a bimolecular pathway that engages the Mo≡CR entities in a stoichiometric triple‐bond metathesis event to furnish RC≡CR and the corresponding dinuclear complex, 8, with a Mo≡Mo core. In addition to the regular analytical techniques, 95Mo NMR was used to confirm this unusual outcome. This rapid degradation mechanism is largely avoided by increasing the size of the peripheral substituents on silicon, without unduly compromising the activity of the resulting complexes. When chemically challenged, however, canopy catalysts can open the apparently somewhat strained tripodal ligand cages; this reorganization leads to the formation of cyclo‐tetrameric arrays composed of four metal alkylidyne units linked together via one silanol arm of the ligand backbone. The analogous tungsten alkylidyne complex 6, endowed with a tripodal tris‐alkoxide (rather than siloxide) ligand framework, is even more susceptible to such a controlled and reversible cyclo‐oligomerization. The structures of the resulting giant macrocyclic ensembles were established by single‐crystal X‐ray diffraction. [ABSTRACT FROM AUTHOR]

The involvement of silver in two‐electron AgI/AgIII processes is currently emerging. However, the range of stability of the required and uncommon AgIII species is virtually unknown. Here, the stability of AgIII towards the whole set of halide ligands in the organosilver(III) complex frame [(CF3)3AgX]− (X=F, Cl, Br, I, At) is theoretically analyzed. The results obtained depend on a single factor: the nature of X. Even the softest and least electronegative halides (I and At) are found to form reasonably stable AgIII−X bonds. Our estimates were confirmed by experiment. The whole series of nonradiative halide complexes [PPh4][(CF3)3AgX] (X=F, Cl, Br, I) has been experimentally prepared and all its constituents have been isolated in pure form. The pseudohalides [PPh4][(CF3)3AgCN] and [PPh4][(CF3)3Ag(N3)] have also been isolated, the latter being the first silver(III) azido complex. Except for the iodo compound, all the crystal and molecular structures have been established by single‐crystal X‐ray diffraction methods. The decomposition paths of the [(CF3)3AgX]− entities at the unimolecular level have been examined in the gas phase by multistage mass spectrometry (MSn). The experimental detection of the two series of mixed complexes [CF3AgX]− and [FAgX]− arising from the corresponding parent species [(CF3)3AgX]− demonstrate that the Ag−X bond is particularly robust. Our experimental observations are rationalized with the aid of theoretical methods. Smooth variation with the electronegativity of X is also observed in the thermolyses of bulk samples. The thermal stability in the solid state gradually decreases from X=F (145 °C, dec.) to X=I (78 °C, dec.) The experimentally established compatibility of AgIII with the heaviest halides is of particular relevance to silver‐mediated or silver‐catalyzed processes. [ABSTRACT FROM AUTHOR]

In order to improve and extend the rare class of tetrahedral mixed main group transition metal compounds, a new synthetic route for the complexes [{CpMo(CO)2}2(μ,η2:η2‐PE)] (E=As (1), Sb (2)) is described leading to higher yields and a decrease in reaction steps. Via this route, also the so far unknown heavier analogues containing AsSb (3 a), AsBi (4) and SbBi (5) ligands, respectively, are accessible. Single crystal X‐ray diffraction experiments and DFT calculations reveal that they represent very rare examples of compounds comprising covalent bonds between two different heavy pnictogen atoms, which show multiple bond character and are stabilised without any organic substituents. A simple one‐pot reaction of [CpMo(CO)2]2 with ME(SiMe3)2 (M=Li, K; E=P, As, Sb, Bi) and the subsequent addition of PCl3, AsCl3, SbCl3 or BiCl3, respectively, give the complexes 1–5. This synthesis is also transferable to the already known homo‐dipnictogen complexes [{CpMo(CO)2}2(μ,η2:η2‐E2)] (E=P, As, Sb, Bi) resulting in higher yields comparable to those in the literature reported procedures and allows the introduction of the bulkier and better soluble Cp′ (Cp′=tert butylcyclopentadienyl) ligand. [ABSTRACT FROM AUTHOR]

The propensity of organic fluorine acting as a weak hydrogen bond acceptor (HBA) in intermolecular and intramolecular interactions has been the subject of many experimental and theoretical studies often reaching different conclusions. Over the last few years, new and stronger evidences have emerged for the direct involvement of fluorine in weak hydrogen bond (HB) formation. However, not all the fluorine atom types can act as weak HBA. In this work, the differential HBA propensity of various types of fluorine atoms was analyzed with a particular emphasis for the different types of alkyl fluorides. This was carried out by evaluating ab initio computed parameters, experimental 19F NMR chemical shifts and small molecule crystallographic structures (extracted from the CSD database). According to this analysis, shielded (with reference to the 19F NMR chemical shift) alkyl mono‐fluorinated motifs display the highest HBA propensity in agreement with solution studies. Although much weaker than other well‐characterized HB complexes, the fragile HBs formed by these fluorinated motifs have important implications for the chemical‐physical and structural properties of the molecules, chemical reactions, and protein–ligand recognition. [ABSTRACT FROM AUTHOR]

Utilizing facile one‐electron oxidation of 10H‐phenothiazine by molecular diiodine, the solid‐state structure of the 10H‐phenothiazinium radical cation was obtained in three cation:iodide ratios, as well as its THF and acetone solvates. Oxidation of 10H‐phenothiazine with molecular diiodine in DMSO or DMF provided the structure of the radical coupling product 10‐(3‐phenothiazinyldene)phenothiazinium, which has not been crystallographically characterized to date. The radical cations were balanced by a mixture (I7)−, (I5)−, (I3)−, and I− anions, where a variety of chalcogen, halogen, and hydrogen bonding interactions stabilize the structures to reveal these interesting cationic species. [ABSTRACT FROM AUTHOR]

The catalytic, enantioselective oxidative cyclization of naphthol-derived carboxylic acids mediated by chiral hypervalent iodine reagents has been studied extensively in the recent past, but analogous reactions of non-carboxylic substrates are yet unknown. This paper describes a catalytic, enantioselective, hypervalent iodine-promoted oxidative cycloetherification reaction of naphtholic alcohols. The new process relies on a variant of the Uyanik-Ishihara catalyst, in which the stereogenic centers have been relocated closer to the iodine atom. The new catalyst design affords optical yields comparable to those available with Uyanik-Ishihara iodides, but chemical yields are sensibly higher, at least with the tests substrates. An even more problematic reaction is the catalytic, enantioselective oxidative cyclization of naphtholic sulfonamides. In this case, the new catalyst affords significantly higher optical inductions than Uyanik-Ishihara iodides. The kinetic resolution of particular naphtholic alcohols is demonstrated. The absolute configuration of a numver of enantioenriched compounds obtained in this study was ascertained by X-ray diffractometry. [ABSTRACT FROM AUTHOR]

Campestarenes are a new family of Schiff-base macrocycles that form selectively in a one-step synthesis. These macrocycles with five-fold symmetry show solvent-dependent tautomerization and dimerization or aggregation. In this paper, we have prepared new soluble campestarenes that do not aggregate. The initial single-crystal X-ray diffraction study of a campestarene reveals that these macrocycles are nearly flat. The tautomeric behavior of the campestarenes has been extensively studied by variable-temperature, multinuclear NMR spectroscopy, UV/Vis spectroscopy, and IR spectroscopy. In polar solvents, such as DMF, the molecules exist predominantly in their keto-enamine form, but the enol-imine tautomer is dominant in non-polar solvents. A detailed computational study of the tautomeric forms of campestarenes provides a theoretical basis for their behavior and corroborates the experimental data. The results of this study give the first comprehensive understanding of the electronic and spectroscopic properties of these pentagonal macrocycles. [ABSTRACT FROM AUTHOR]

Herein, it is reported that the polymorphism in the helical nanofilament (HNF, B4) liquid‐crystalline phase depends on the fabrication methods, that is, UV‐driven formation and template‐assisted self‐assembly in the nanoconfined geometry. As a result, uniaxially oriented HNFs with different helical structures were obtained, in which generation of the twisted‐ribbon and cylindrical‐ribbon polymorphs showed that even the molecular lattice has a different orientation. The detailed structures were directly observed by SEM and grazing‐incidence X‐ray diffraction with synchrotron radiation. The resultant polymorphs could be used in chiro‐optical applications due to the capability for fine control of the helical structures. [ABSTRACT FROM AUTHOR]

Based on the results from previous high‐pressure experiments on the gadolinite‐type mineral datolite, CaBSiO4(OH), the behavior of the isostructural borates β‐HfB2O5 and β‐ZrB2O5 have been studied by synchrotron‐based in situ high‐pressure single‐crystal X‐ray diffraction experiments. On compression to 120 GPa, both borate layer‐structures are preserved. Additionally, at ≈114 GPa, the formation of a second phase can be observed in both compounds. The new high‐pressure modification γ‐ZrB2O5 features a rearrangement of the corner‐sharing BO4 tetrahedra, while still maintaining the four‐ and eight‐membered rings. The new phase γ‐HfB2O5 contains ten‐membered rings including the rare structural motif of edge‐sharing BO4 tetrahedra with exceptionally short B−O and B⋅⋅⋅B distances. For both structures, unusually high coordination numbers are found for the transition metal cations, with ninefold coordinated Hf4+, and tenfold coordinated Zr4+, respectively. These findings remarkably show the potential of cold compression as a low‐energy pathway to discover metastable structures that exhibit new coordinations and structural motifs. [ABSTRACT FROM AUTHOR]

The mechanism for the mechanochemical synthesis of (C(NH2)3)3PbI53 and (C(NH2)3)4PbI64 and their conversion into each other is presented. We investigated the synthesis of 3 at different frequencies and energies using in situ powder X‐ray diffraction. By splitting the reaction into single parts we could prove that the formation of 3 is simply dependent on the energy and mixing speed. The nucleation of 4 instead is slightly negative dependent on the energy but dependent on the mixing speed, while its growth is mostly independent of any influence. We were able to influence the reaction pathways by seeding the mixture with a small amount of powdery 4. The formation of 4 is very likely an auto‐catalytic process. 3 instead is metastable. It can be stabilized by energy, which beside mechanochemistry can also be achieved by temperature. The results showcases the complex nature of mechanochemical reactions. [ABSTRACT FROM AUTHOR]

To develop new and flexible CuI containing luminescent substances, we extend our previous investigations on two metal‐centered species to four metal‐centered complexes. These complexes could be a basis for designing new organic light‐emitting diode (OLED) relevant species. Both the synthesis and in‐depth spectroscopic analysis, combined with high‐level theoretical calculations are presented on a series of tetranuclear CuI complexes with a halide containing Cu4X4 core (X=iodide, bromide or chloride) and two 2‐(diphenylphosphino)pyridine bridging ligands with a methyl group in para (4‐Me) or ortho (6‐Me) position of the pyridine ring. The structure of the electronic ground state is characterized by X‐ray diffraction, NMR, and IR spectroscopy with the support of theoretical calculations. In contrast to the para system, the complexes with ortho‐substituted bridging ligands show a remarkable and reversible temperature‐dependent dual phosphorescence. Here, we combine for the first time the luminescence thermochromism with time‐resolved FTIR spectroscopy. Thus, we receive experimental data on the structures of the two triplet states involved in the luminescence thermochromism. The transient IR spectra of the underlying triplet metal/halide‐to‐ligand charge transfer (3M/XLCT) and cluster‐centered (3CC) states were obtained and interpreted by comparison with calculated vibrational spectra. The systematic and significant dependence of the bridging halides was analyzed. [ABSTRACT FROM AUTHOR]

The oxidation of a Siamese ‐ twin Porphyrin, a pyrazole ‐ containing meso ‐ phenyl ‐ substituted expanded porphyrin, leads to the successive formation of two Npyrazole – Co ‐ Ph bonds with a concomitant folding of the macrocycle conformation. This Full Paper describes the synthesis, spectroscopic characterization, and crystal ‐ structure analyses of these unusual macrocycles, containing pyrazoloindole building blocks. Similarly to the parent compound, the oxidized structures do not possess macrocycle aromatic π systems. NMR data suggest that the solid ‐ state structures are maintained in solution. More information can be found in the Full Paper by C. Brückner, F. Meyer, et al. on page 2307 ff. [ABSTRACT FROM AUTHOR]

The effects of solution‐state dielectric and intermolecular interactions on the degree of charge separation provide a route to understanding the switching properties and concentration dependence of donor–acceptor Stenhouse adducts (DASAs). Through solvatochromic analysis of the open‐form DASA in conjunction with X‐ray diffraction and computational theory, we have analyzed the ionic character of a series of DASAs. First‐ and third‐generation architectures lead to a higher zwitterionic resonance contribution of the open form and a zwitterionic closed form, whereas the second‐generation architecture possesses a less charge‐separated open form and neutral closed form. This can be correlated with equilibrium control and photoswitching solvent compatibility. As a result of the high contribution of the zwitterionic resonance forms of first‐ and third‐generation DASAs, we were able to control their switching kinetics by means of ion concentration, whereas second‐generation DASAs were less affected. Importantly, these results show how the previously reported concentration dependence of DASAs is not universal, and that DASAs with a more hybrid structure in the open form can achieve photoswitching at high concentrations. [ABSTRACT FROM AUTHOR]

Silylated chalconium ions based on peri ‐ naphthalene and acenaphthene scaffolds are synthesized and introduced as versatile amphiphilic reagents. The investigation of their spectroscopic, structural and bonding properties revealed that their silyl Lewis acidity is controlled by the nature of the chalcogen donor and by the carbon backbone. This opens the perspective for an effective fine tuning and control of their reactivity. Their use as amphiphilic CATalyst was exemplarily demonstrated in hydrodefluorination reactions. More information can be found in the Full Paper by T. Müller et al. on page 10068. [ABSTRACT FROM AUTHOR]

Carbon quantum dots (CQDs) have recently attracted significant attention for both their fundamental science and technological applications as a new class of fluorescent zero-dimensional nanomaterials with a size below 10 nm. However, the reported methods of synthesis were generally less suitable for the large-scale production of the CQDs with high-fluorescent quantum yield (QY). In the paper, a novel one-pot microwave-assisted drying synthesis approach was presented to prepare CQDs with high QY of 61.3 % for the first time. The production yield of CQDs was 35±3 % in weight. The as-prepared CQDs were characterized by various techniques such as TEM, AFM, XRD, XPS, FTIR spectroscopy, UV/Vis absorption spectroscopy, and fluorescence spectroscopy. The results showed that the high QY of CQDs was largely attributed to the dual doping of nitrogen and sulphur into CQDs. Such CQDs were then used as live-cell imaging reagents due to their high QY, good water dispersibility, fine biocompatibility, high photostability, and low cytotoxicity. [ABSTRACT FROM AUTHOR]

The first synthesis of BePh2 was accomplished almost a century ago. However, its structure has remained unknown so far, while the corresponding aryls of the elements adjacent to beryllium in the periodic table are well investigated. Herein, we present an improved synthesis for diphenylberyllium and show by X‐ray diffraction that it forms a trinuclear complex in the solid state. NMR spectroscopy revealed that this structure is also retained in solution but exhibits dynamic behavior. Its stability against heat and coordinating solvents is discussed and the possible obstacles to the synthesis of BePh2 from BeCl2 are examined. In the process of this study two ether adducts, BePh2⋅Et2O and Be2Ph4⋅Et2O, have been characterized as well as the previously unknown triphenylberyllate anion. From the latter several single‐crystal structures were obtained under various conditions, in which [BePh3]− is either isolated or acts as a ligand for Li+. Furthermore, the crown ether induced selfionization of BePh2 is described and the resulting [(12‐crown‐4)BePh]+ cation was isolated, which shows an unusual 4+1 coordination around the Be atom. [ABSTRACT FROM AUTHOR]

A preorganized anion binding site at the positive end of the 2.5 ‐ helix macrodipole. NMR titration studies revealed the ability of helical aliphatic oligourea foldamers to bind anionic guests without unfolding. The encounter between a 2.5 ‐ helical oligourea and an anionic species is transposed on this figure to a football field with the helix as a goalkeeper and the anionic guest as the football. The positive and negative poles of the helix macrodipole are shown in blue and red respectively. More information can be found in the Full Paper by G. Guichard et al. on page 15684 ff. [ABSTRACT FROM AUTHOR]

Looking into the black box: The combination of time‐resolved powder X‐ray diffraction monitoring using the Oxford‐Diamond in situ cell (ODISC) and complementary ex situ investigations shed new light on the hydrothermal formation of spinel‐type Co3O4 water oxidation catalysts. Our complementary approach provides access to fundamental synthesis‐activity correlations for enhancing the water oxidation efficiency of cost‐effective and stable Co3O4. This strategy has high potential for monitoring a wide range of crystal growth mechanisms behind primarily empirical "black box" hydro‐/solvothermal processes in energy materials development. For more information, see the Full Paper by G. R. Patzke et al. on page 18424 ff. [ABSTRACT FROM AUTHOR]

The reaction paths in the formation of four hybrid organic–inorganic guanidinium lead(II) iodides were followed by in situ synchrotron powder X‐ray diffraction measurements, revealing complex reaction mechanisms. The compounds show large differences in their respective nucleation and growth speeds, as evidenced by their interconversion and intermediate formation. These observations are related to the different arrangements of the inorganic‐organic moieties in the respective compounds, the crystal structures having been solved by powder X‐ray diffraction. They differ in composition, dimensionality of the inorganic framework and the strength of ionic interactions; a link is proposed between these features and the reaction mechanisms. For more details, see the Full Paper by N. Casati and M. Wilke on page 17701 ff. [ABSTRACT FROM AUTHOR]

Bifacial tin aromatics: The first stable tin‐containing benzene derivative, stannabenzenyl anion, was successfully isolated as a monomer both in solution and in the solid state by the reaction of the equilibrated mixture of a monomeric stannabenzene and its dimer with potassium graphite. The results of the X‐ray crystallographic analysis, NMR and UV/Vis spectroscopic measurements, and theoretical calculations indicated that the stannabenzenyl anion shows the contribution of stannylene character, while it has an aromatic character. In addition, several reactions of the stannabenzenyl anion were performed to reveal its unique reactivity. More information can be found in the Full Paper by N. Tokitoh, Y. Mizuhata, and S. Fujimori on page 17039. [ABSTRACT FROM AUTHOR]

Carbonate Halides Three new carbonate halides, Cs3Pb2(CO3)3I (CPCI), KBa2(CO3)2F (KBCF), and RbBa2(CO3)2F (RBCF) are reported by Y. Yang, Z. Yang, S. Pan et al. in their Full Paper on page 2944 ff. CPCI features a 2D layered structure, which, owing to the arrangement of CO3 units and the stereoactive Pb2+, displays moderate birefringence. KBCF and RBCF adopt a honeycomb‐like framework. Through comparison of these structures with other carbonate fluorides, it is illustrated that the quantity and distribution of O atoms and the position of divalent cations play essential roles in determining the arrangement of CO3 groups. [ABSTRACT FROM AUTHOR]

A combination of1H NMR, 2D diffusion NMR spectroscopy, electrospray ionization travelling wave ion‐mobility mass spectrometry, small‐angle X‐ray scattering, and molecular modelling allowed the unambiguous characterization of an original covalent polyoxometalate‐based molecular triangle. More details of this fascinating chemistry can be found in the Full Paper by G. Izzet and co‐workers on page 19010 ff. [ABSTRACT FROM AUTHOR]

Shatruk and Alabugin propose an alternative structural model for the observed electron density that we have attributed to the photochemical formation of 1,3-dimethylcyclobutadiene in a protective solid crystalline matrix. The main criticism from Shatruk and Alabugin concerns the modeling of the disorder in the calixarene cavity and in particular the neglect of a residual electron density close to the O1 atom. We published ( Chem. Eur. J. 2011, 17, 10021) our opinion concerning this 'ignored peak' in the Supporting Information of the paper. The current response to the Correspondence demonstrates that Shatruk and Alabugin have over-modeled our data by assigning a small electron density peak, which is hardly more than the density corresponding to a hydrogen atom, to an under-occupied oxygen site, using inappropriate refinement contraints. [ABSTRACT FROM AUTHOR]

This unique complex study describes two isomeric aminotriazoles as auspicious nitrogen‐rich ligands for energetic coordination compounds (ECCs) to replace the commonly used highly poisonous and environmentally harmful lead‐based primary explosives. The triazoles were obtained by easily scalable and convenient synthetic routes starting solely from commercially available starting materials. 1‐Amino‐1,2,3‐triazole (1, 1‐ATRI) and, for the first time, 1‐amino‐1,2,4‐triazole (2, 1A‐1,2,4‐TRI) were employed as ligands to form highly energetic transition‐metal(II) complexes. The desired characteristics could be altered successively by using various nonpoisonous metal(II) centers (Cu2+, Mn2+, Fe2+, and Zn2+) and anions (Cl−, NO3−, ClO3−, ClO4−, picrate, styphnate, 2,4,6‐trinitro‐3‐hydroxyphenolate, and 2,4,6‐trinitro‐3,5‐dihydroxyphenolate). The 14 synthesized coordination compounds were characterized comprehensively by XRD, IR and UV/Vis spectroscopy, elemental analysis, and differential thermal and thermogravimetric analyses. Ball‐drop impact, electrostatic discharge (ESD), and mechanical (impact and friction) sensitivities were determined according to BAM standard methods. In addition to laser ignition experiments, selected ECCs were evaluated in classical secondary explosive initiation tests (detonators filled with pentaerythritol tetranitrate (nitropenta)), which revealed their enormous potential and proved them to be very attractive for future applications in explosives. Developing explosives: The nitrogen‐rich aminotriazole ligands 1‐amino‐1,2,3‐triazole and 1‐amino‐1,2,4‐triazole have been successfully employed as suitable building blocks in 14 new energetic transition‐metal complexes. By varying the metals and anions, a variety of different functional materials have been synthesized, some of which have shown great potential as laser‐ignitable and classical primary explosives (see figure). [ABSTRACT FROM AUTHOR]

The synthesis and solid‐state molecular structures of two dichlorido(aryl)(alkyl) tin compounds, 5 and 8, both key intermediates to tunable polystannane architectures, are reported. The materials were further investigated by single‐crystal XRD and a DFT analysis of their preferential "open and closed" geometries. Conversion of said compounds to their dihydride analogues was undertaken, followed by their application as monomers for polystannane polymer synthesis. The properties of two asymmetrical polystannanes prepared by transition‐metal‐catalyzed dehydropolymerization of dihydrido(aryl)alkylstannanes (6 and 9) were investigated. The first product was the structurally simple, modest molecular weight, semi‐crystalline light‐ and moisture‐stable polystannane 10 with NMR (119Sn) evidence of prominent Sn←O hypercoordination along the polymer backbone. The second was the lower molecular weight, tosylated four‐coordinate polystannane 11 with no evidence of hypercoordination. Differential scanning calorimetry (DSC) of polymer 10 revealed a reversible semi‐crystalline nature, whereas an amorphous character was detected for polymer 11. Polystannane 10 was also found to be exceptionally stable to both moisture and light (>6 months) and a promising candidate for the design of readily modified (i.e., tunable) polystannane materials. Building polystannanes: A simple light‐ and moisture‐stable semi‐crystalline hypercoordinated polystannane is revealed: A key design feature for asymmetrical polystannanes is the use of strongly dative‐bonded ligands that render the majority of tin(IV) centers of this main‐group inorganic polymer pentacoordinate, electron rich and protected from nucleophilic attack. [ABSTRACT FROM AUTHOR]

The self‐assembly properties of nine low‐molecular‐weight gelators (LMWGs) based on bile acid alkyl amides were studied in detail. Based on the results, the number of hydroxyl groups attached to the steroidal backbone plays a major role in the gelation, although the nature of the aliphatic side chain also modulates the gelation abilities. Of the 50 gel systems studied, 35 are based on lithocholic acid and 15 on cholic acid derivatives. The deoxycholic acid derivatives did not form any gels. The gelation occurred primarily in aromatic solvents and the gels manifested typical fibrous or spherical morphologies. The 13C cross‐polarized magic angle spinning (CPMAS) NMR spectra measured on the crystalline materials and the corresponding wet organogels were analogous, suggesting that the chemical environments, that is, the intermolecular interactions found in the two materials were similar. The single‐crystal X‐ray structures of all nine bile‐acid amide derivatives studied revealed very similar molecular conformations in the solid state and gave insights into the possible intermolecular interactions in the gel state. A detailed study on the self‐assembly properties of nine low‐molecular‐weight gelators based on bile acid alkyl amides resulted in 50 gel systems, 35 of which were based on lithocholic acid and 15 on cholic acid derivatives. Deoxycholic acid derivatives did not form gels. Gelation was observed in aromatic solvents and the gels showed typical fibrous or spherical morphologies. Solid‐state NMR and single‐crystal XRD investigations gave insights into the possible intermolecular interactions in the gel. [ABSTRACT FROM AUTHOR]

Two series of trimetallic {NiIIxCoII9−x[WV(CN)8]6} (NiCoW) and {MnIIxCoII9−x[WV(CN)8]6} (MnCoW) (x=1–8) crystalline solid‐solutions were constructed and systematically studied by SEM EDX, single‐crystal X‐ray diffraction (SC XRD), and magnetic measurements. The atomic Ni:Co:W and Mn:Co:W ratios in the solid state follow the stoichiometric concentration in the mother MeOH solutions fairly well. The structural studies revealed a definite strong tendency of smaller 3d ions to locate in the central [M(μ‐NC)6] moiety of the skeleton: NiII over the CoII and CoII over MnII. In contrast, the external fac‐[M(μ‐NC)3(MeOH)3] are consecutively occupied by the mixture of 3d metal ions, accessible according to the stoichiometry of the mother solutions. The DC magnetic χT(T) and M(H) curves illustrate the continuous tendency of change with x along both series, nicely reproducing the changes of the theoretical high spin in the ground state Sgr, assuming the ferromagnetic HSCoII‐NC‐WV and antiferromagnetic MnII‐NC‐WV interactions established by numerous literature reports. The AC magnetic measurements indicate the occurrence of slow magnetic relaxation, with the highest energy barrier ΔE/kB of 26 K for the Ni6Co3W6 congener and of 17 K for the Mn6Co3W6 congener, and relatively large values of distribution parameter α. The values of ΔE are correlated with possible anisotropy of distribution of fac‐[CoII(μ‐NC)3(MeOH)3] moieties at the external corners of the cube substructure. Clusters: The series of trimetallic cyanido‐bridged NiCoW and MnCoW cluster‐based crystalline phases exhibit 3d metal ion site‐specific occupation, continuous change of the spin in the ground state Sgr, and tunable magnetic relaxation due to the disproportion in the number of different 3d ions at the external coordination sites. [ABSTRACT FROM AUTHOR]

Sodium salicylate (2‐hydroxybenzoate) has been fully characterised by single‐crystal X‐ray diffraction (SCXRD), thermogravimetric analysis in combination with in operando FTIR spectroscopy and GC‐MS, as well as by UV/Vis absorption and photoluminescence spectroscopy backed up by DFT calculations. SCXRD revealed a layered crystal structure composed of ionic sheets formed by Na+–O contacts sandwiched between π‐stacked aromatic rings of the salicylate anion oriented perpendicular to the layer plane. Only weak van der Waals interactions hold the individual sheets together. No solid/solid or solid/liquid phase transitions were observed upon heating, but a three‐step decomposition was observed, with the first onset at 245 °C corresponding to concomitant release of CO2 and phenol. The UV/Vis absorption spectra show temperature‐dependent absorption bands at around 305 and/or 345 nm, which according to DFT calculations correspond to the absorption of the carboxylate or phenolate proton transfer species, respectively. In solution, indications of the phenolate species are found only in a very apolar solvent (cyclohexane). Because of excited‐state relaxation, emission always occurs from the phenolate structure, which explains the large Stokes shift. Piling on the layers: Sodium salicylate has been for the first time fully characterised by single‐crystal XRD, TGA in combination with in operando FTIR spectroscopy and GC‐MS, as well as by UV/Vis and photoluminescence spectroscopy backed up by DFT calculations. Its layered crystal structure is made up of ionic Na–O sheets sandwiched between π‐stacked aromatic rings oriented perpendicular to the layer plane (see figure). Proton transfer within the ionic layers is identified as the reason for the particular luminescence behaviour. [ABSTRACT FROM AUTHOR]

Synthesis of a series of cationic coinage metal (Au: 2–4, Ag: 5, and Cu: 6) complexes of asymmetric diborenes (1 a, 1 b) is reported. X‐ray diffraction analysis reveals that the metal center interacts unsymmetrically with the B2 moiety and the terminal boron atom exhibits pronounced pyramidal geometry. A computational study shows that in complexes 2–6, the bonding between the B2 units and the metal center is dominated by electrostatic interactions concomitant with non‐negligible covalent contributions. To coin a complex: A series of cationic coinage metal (Au: 2–4, Ag: 5, and Cu: 6) complexes of asymmetric diborenes (1 a, b) have been synthesized. X‐ray diffraction analysis reveals that the metal center interacts unsymmetrically with the B2 moiety and the terminal boron atom exhibits pronounced pyramidal geometry. The computational study shows that in the complexes the bonding between the B2 units and the metal centers is dominated by electrostatic interactions (see scheme). [ABSTRACT FROM AUTHOR]

Abstract: Modification of the magnetic properties in a solid‐state material upon external stimulus has attracted much attention in the recent years for their potential applications as switches and sensors. Within the field of coordination polymers, gas sorption studies typically focus on porous solids, with the gas molecules accommodating in the channels. Here we present a 1D non‐porous coordination polymer capable of incorporating HCl gas molecules, which not only causes a reordering of its atoms in the solid state but also provokes dramatic changes in the magnetic behavior. Subsequently, a further solid–gas transformation can occur with the extrusion of HCl gas molecules causing a second structural rearrangement, which is also accompanied by modification in the magnetic path between the metal centers. Unequivocal evidence of the two‐step magnetostructural transformation is provided by X‐ray single‐crystal diffraction. [ABSTRACT FROM AUTHOR]

Abstract: Alloys of platinum and gadolinium present significant activity enhancement over pure Pt for the oxygen reduction reaction (ORR), both in the form of extended electrode surfaces and nanoparticulate catalysts. The active phase consists of a compressed Pt overlayer formed on Pt5Gd electrodes upon exposure to the electrolyte by acid leaching. Here, we investigate the formation, strain and correlation lengths of the active Pt overlayer by using in situ synchrotron grazing incidence X‐ray diffraction on Gd/Pt(111) single‐crystalline electrodes. The overlayer forms upon exposure to electrolyte under open circuit conditions; the compressive strain relaxes slightly upon repeated electrochemical cycling in the potential range 0.6 to 1.0 V versus the reversible hydrogen electrode (RHE). In addition, the strain relaxes strongly when exposing the electrode to 1.2 V versus RHE, and the thickness of the crystalline portion of the overlayer increases with potential above 1.3 V versus RHE. [ABSTRACT FROM AUTHOR]

Abstract: The complex trans‐[Pt(F)(SF3)(PCy3)2] (1) shows a diverse reactivity pattern at the SF3 ligand towards ethanol and Me3SiOEt. This led by deoxyfluorination or alcoholysis to the generation of platinum complexes bearing a metal‐bound S(O)F or S(OEt)2 group. For the latter reaction trans‐[Pt(F){S(F)(OEt)2}(PCy3)2] is suggested as an intermediate. In reactivity studies of trans‐[Pt(F)(SF2)(PCy3)2][BF4] the complex [Pt(F){S(F)(OEt)}(PCy3)2][BF4] was prepared, which does not react with ethanol. [ABSTRACT FROM AUTHOR]

Abstract: Ammonia decomposition is an important technology for extracting hydrogen from ammonia toward the realization of a hydrogen economy. Herein, it is reported that large oblate hemispheroidal Ru particles on Ca(NH2)2 function as efficient catalysts for ammonia decomposition. The turnover frequency of Ru/Ca(NH2)2 increased by two orders of magnitude when the Ru particle size was increased from 1.5 to 8.4 nm. More than 90 % ammonia decomposition was achieved over Ru/Ca(NH2)2 with large oblate hemispheroidal Ru particles at 360 °C, which is comparable to that of alkali‐promoted Ru catalysts with small Ru particle sizes. XAFS analyses revealed that Ru particles are immobilized on Ca(NH2)2 by Ru−N bonds formed at the metal/support interface, which lead to oblate hemispheroidal Ru particles. Such a strong metal–support interaction in Ru/Ca(NH2)2 is also substantiated by DFT calculations. The high activity of Ru/Ca(NH2)2 with large Ru particles primarily originates from the shape and appropriate size of the Ru particles with a high density of active sites rather than the electron‐donating ability of Ca(NH2)2. [ABSTRACT FROM AUTHOR]

The coordination chemistry of complexes featuring a PNP ligand framework and the redox active lanthanide ion, cerium(III), was initiated. The cerium(III) ion induced the transformation of one of the phosphino donor arms at a parent PNP ligand into a new phosphido functionality. The Ce−PNP systems were also employed for C−C bond‐forming reactions and the molecular structures of Ce−PNP complexes were studied both in solution and in the solid state. More information can be found in the Full Paper by O. V. Ozerov, E. J. Schelter et al. on page 17923. [ABSTRACT FROM AUTHOR]

Five new mixed ‐ metal borates, namely, K2BaB16O26, K3CsB20O32, Na2Cs2BaB18O30, Na2Rb2PbB18O30, and Na2Cs2PbB18O30 were synthesized by using the high ‐ temperature solution method. These structures were characterized by single ‐ crystal X ‐ ray diffraction and their B−O configurations feature three ‐ dimensional open ‐ framework structures with different types of channels. The frameworks can be reduced into four ‐ connected uninodal net with sra ‐ , dia ‐ , and nbo ‐ type topology by assigning the 4 ‐ c [B5O10]5− and [B3O7]5− clusters as basic nodes. For more information, see the Full Paper by M. Zhang, Z. Yang, and S. Pan et al. on page 13910 ff. [ABSTRACT FROM AUTHOR]

A new boron complex for obtaining aggregation ‐ induced emission properties was designed based on the strategy to improve the flexibility of a molecular skeleton. From the computer calculation and synthesis, the desired complex with environment ‐ sensitive solid ‐ state emission was obtained. Furthermore, the complex showed thermosalient effects in the heating and cooling processes with luminescent chromism. More information can be found in the Full Paper by K. Tanaka, Y. Chujo et al. on page 11827. [ABSTRACT FROM AUTHOR]

The concept of mixing a highly anisotropic system with a soft magnet, which is the approach commonly used to fabricate permanent magnets with large magnetic hysteresis, can also be developed in the molecular world. Instead of preparing metallic alloys formed by 3d metals with anisotropic lanthanides (such as NdFe14B), a molecular approach was used to design a hybrid crystalline lattice formed by an anisotropic single molecule magnet (SMM) incorporated into a bimetallic oxalate 3D ferromagnetic network. Thanks to the antiferromagnetic interaction established between these two magnetic networks, a large increase in the coercive field has been observed at low temperatures. For more details, see the Full Paper on page 1669 ff. by M. Clemente ‐ León et al. [ABSTRACT FROM AUTHOR]

Phosphorus sulfides have been known for over 270 years and are familiar to us in strike ‐ anywhere matches, which contain P4S3. Many phosphorus – sulfur and phosphorus – selenium compounds have been discovered and characterized but, in contrast, phosphorus – tellurium compounds are quite rare, since it is difficult to stabilise the PTe and PTe bonds. In their Full paper on page 704 ff. J. D. Woollins and co ‐ workers present the first crystal structures of organophosphorus(III) – tellurium heterocycles, which can be stabilized and structurally characterized by the appropriate choice of bulky substituents or the installation of a PV2N2 anchor. [ABSTRACT FROM AUTHOR]

The activity of photoreceptor proteins can be reduced by detrimental radical side reactions. The evolution of radicals in a single crystal of a model molecule for the chromophore of the photoactive yellow protein (PYP) is destructive for the integrity of the tightly packed single crystal. “Dilution” of the structure of the chromophore with water molecules helps retain crystallinity during the photoreaction, providing means for direct observation of the photodimerization reaction by X‐ray diffraction. For more details see the Full Paper by P. Naumov et al. on page 8094 ff. [ABSTRACT FROM AUTHOR]

Reactions of rare‐earth‐metal methylidene complexes with imines, azobenzenes, or amines result in the access to a wide variety of imido rare‐earth‐metal complexes, providing three new routes to such rare‐earth‐metal imido complexes. L. Zhang, X. Zhou et al. present an example of trivalent rare‐earth‐metal‐promoted activation of azobenzene and imines to form the corresponding imido complexes in their Full Paper on page 7865 ff. The cover picture shows three different transportation ways from Shanghai to Rome, representing three synthetic pathways to objective complexes. As the saying goes, all roads lead to Rome; similarly imido rare‐earth‐metal complexes can be obtained by various protocols. [ABSTRACT FROM AUTHOR]

We have developed highly porous Cu‐based metal–organic frameworks (MOFs) using carbazole‐type linkers. The novel topological structure of these MOFs was revealed by single‐crystal X‐ray diffraction analysis. Molecular adsorption/desorption experiments indicated that these MOFs are flexible and change their structure upon adsorption/desorption of organic solvents and gas molecules. These MOFs exhibit unprecedented properties that allow controlling their flexibility by adding a functional group onto the central benzene ring of the organic ligand. For example, the introduction of electron‐donating substituents increases the robustness of the resulting MOFs. These MOFs also exhibit flexibility‐dependent differences in gas‐adsorption and ‐separation performance. Thus, this study represents the first example of controlling the flexibility of MOFs with the same topological structure via the substituent effect of functional groups introduced into the organic ligand. [ABSTRACT FROM AUTHOR]

A missing family of the extremely air sensitive tripentelyltrielanes was discovered. Their stabilisation was achieved by using the bulky NHC IDipp (NHC=N‐heterocyclic carbene, IDipp=1,3‐bis(2,6‐diisopropylphenyl)‐imidazolin‐2‐ylidene). The tripentelylgallanes and tripentelylalanes IDipp ⋅ Ga(PH2)3 (1 a), IDipp ⋅ Ga(AsH2)3 (1 b), IDipp ⋅ Al(PH2)3 (2 a) and IDipp ⋅ Al(AsH2)3 (2 b) were synthesised by salt metathesis of IDipp ⋅ ECl3 (E=Al, Ga, In) with alkali metal pnictogenides such as NaPH2/LiPH2 ⋅ DME and KAsH2, respectively. Moreover, the detection of the first NHC‐stabilised tripentelylindiumane IDipp ⋅ In(PH2)3 (3) was possible by multinuclear NMR spectroscopy. Initial investigations of the coordination ability of these compounds resulted in the successful isolation of the coordination compound [IDipp ⋅ Ga(PH2)2(μ3‐PH2{HgC6F4}3)] (4) by reaction of 1 a with (HgC6F4)3. The compounds were characterised by multinuclear NMR spectroscopy as well as single crystal X‐ray diffraction studies. Supporting computational studies highlight the electronic features of the products. [ABSTRACT FROM AUTHOR]

The reactivity of carbonyl diisocyanate, CO(NCO)2, and carbonyl diisothiocyanate, CO(NCS)2 with nucleophiles shows different patterns: Whereas carbonyl diisocyanate adds two equivalents of nucleophile forming carbonyl bis(carbamoylhalides), carbonyl diisothiocyanate only adds one equivalent and undergoes intramolecular ring closure, resulting in the formation of substituted thiadiazines. In this study we have reacted both carbonyl diisocyanate and carbonyl diisothiocyanate with the full series of hydrogen halides HF to HI, isolating carbonyl bis(carbamoylfluoride) (1), ‐chloride (2), ‐bromide (3), and ‐iodide (4) as well as (6‐chloro‐2,3‐dihydro‐2‐thioxo‐4H‐1,3,5‐thiadiazin‐4‐one (5), and 6‐bromo‐2,3‐dihydro‐2‐thioxo‐4H‐1,3,5‐thiadiazin‐4‐one (6). The compounds were analysed by single‐crystal X‐ray diffraction, NMR spectroscopy, IR and Raman spectroscopy, and elemental analysis. Quantum mechanical calculations show thermodynamic reasons for the differences in reactivity. [ABSTRACT FROM AUTHOR]