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A formal carbene-transfer reaction from an isolated nickelacyclobutane to an isocyanide to form a ketenimine is reported. DFT calculations support a stepwise 1,1-insertion/fragmentation pathway without a carbene intermediate. This unusual reactivity suggests a potential new role as "carbene reservoir" for nickelacyclobutanes, which are typically seen as intermediates in catalytic cyclopropanation. [ABSTRACT FROM AUTHOR]

We report a templated Scholl oxidation strategy for the preparation of the first β-diketiminate (BDI) ligands embedded within a 24-electron π-system backbone. The resulting benzo[f,g]tetracene BDI ligand was coordinated to a zinc centre and electrochemical studies showed the redox active nature of the ligand. [ABSTRACT FROM AUTHOR]

Low‐valent silicon compounds such as neutral silylenes display versatile reactivity for the activation of small molecules. In contrast, their anionic congeners silanides ([R3Si−]) have primarily been investigated for their nucleophilic reactivity. Here we show that incorporating a silanide center in a bicyclic cage structure allows for formal oxidative addition of polar element‐hydrogen bonds (RX−H, R=aromatic residue, X=O, S, NH). The resulting hydrosilicates were isolated and characterized structurally and spectroscopically. Density Functional Theory (DFT) calculations and experimental observations support an ionic mechanism for RX−H bond activation. Finally, the reactivity of the RS−H bond adduct was further investigated, revealing that it behaves as a Lewis pair upon facile heterolytic cleavage of the Si−S bond. [ABSTRACT FROM AUTHOR]

Low‐valent silicon compounds such as neutral silylenes display versatile reactivity for the activation of small molecules. In contrast, their anionic congeners silanides ([R3Si−]) have primarily been investigated for their nucleophilic reactivity. Here we show that incorporating a silanide center in a bicyclic cage structure allows for formal oxidative addition of polar element‐hydrogen bonds (RX−H, R=aromatic residue, X=O, S, NH). The resulting hydrosilicates were isolated and characterized structurally and spectroscopically. Density Functional Theory (DFT) calculations and experimental observations support an ionic mechanism for RX−H bond activation. Finally, the reactivity of the RS−H bond adduct was further investigated, revealing that it behaves as a Lewis pair upon facile heterolytic cleavage of the Si−S bond. [ABSTRACT FROM AUTHOR]

This article analyses the dynamic and frequently conflictual dimension of establishing transnational coordination in the Siemens kin group during an age of nationalism and imperialism. Recent historiography has emphasised the role of kinship in nineteenth-century globalisation. Scholars point to the role of entrepreneurial families in establishing transnational networks as a means to expand their business beyond regional or national settings. However, this literature considers kinship a priori as a foundation of entrepreneurial success and does not take the constructed character of kin relations into account. Three brothers and their families are at the core of this study: Werner in Berlin, William in London and Carl in St Petersburg. The analysis shows how the vast transnational Siemens enterprise was built on distinctly modern notions of kinship, when the originally Berlin-based firm expanded into a complex transnational entity united by a shared identity of familial connection. In this process, notions of kin were constantly reassessed and renegotiated, centring around the question of how 'German' the Siemens family and their enterprises were perceived to be. We argue that the ability to mediate these conflicts was crucial to the persistence, expansion and intergenerational continuity of Siemens's globalisation strategy, where family and business logics were deeply intertwined. [ABSTRACT FROM AUTHOR]

While German business's complicity in Nazi-era crimes from "Aryanization" to forced labor and mass murder has been well documented by historical research, corporate expansion into occupied Europe has received much less attention. Beyond plundering and labor recruitment we still know little about what German companies actually did abroad and whether it mattered to the actual war effort. The present article follows several electrical and construction companies, among them Siemens, AEG, and Philipp Holzmann, to wartime Ukraine, the most important arena of German economic exploitation in Eastern Europe. It traces their role within the occupation regime, their crucial contribution to the war, and their own goals in the process. Through a detailed examination of the giant, world-renowned hydroelectric power plant DniproGES (Dneprostoi), we argue that private business both literally and metaphorically powered German conquest, occupation, and the continuing war effort. [ABSTRACT FROM AUTHOR]

The Diels–Alder (DA) reaction of furans is a versatile tool in synthetic organic chemistry and in the production of sustainable building blocks and smart materials. Numerous experimental and theoretical investigations suggest that the diene scope is effectively limited to electron-rich furans, which excludes the most abundant and readily accessible renewable derivatives: furfural and its 5-hydroxymethyl homologue. Herein we show for the first time that electron-poor 2-formylfurans can also directly engage in Diels–Alder couplings. The key to success is the use of aqueous medium, which supplies an additional thermodynamic driving force by coupling the unfavorable DA equilibrium to the exergonic hydration of the carbonyl functionality in the adducts to form geminal diols. This finding enables the direct access to various novel DA adducts derived from renewable furfurals and maleimides, via a mild, simple and environmentally-friendly synthetic protocol. [ABSTRACT FROM AUTHOR]

Dioxo‐molybdenum complexes have been reported as catalysts for the deoxydehydration (DODH) of diols and polyols. Here, we report on the DODH of diols using [Cp*MoO2]2O as catalyst (Cp*=1,2,3,4,5‐pentamethylcyclopentadienyl). The DODH reaction was optimized using 2 mol % of [Cp*MoO2]2O, 1.1 equiv. of PPh3 as reductant, and anisole as solvent. Aliphatic vicinal diols are converted to the corresponding olefins by [Cp*MoO2]2O in up to 65 % yield (representing over 30 turnovers per catalyst) and 91 % olefin selectivity, which rivals the performance of other Mo‐based DODH catalysts. Remarkably, cis‐1,2‐cyclohexanediol, which is known as quite a challenging substrate for DODH catalysis, is converted to 30 % of 1‐cyclohexene under optimized reaction conditions. Overall, the mass balances (up to 79 %) and TONs per Mo achievable with [Cp*MoO2]2O are amongst the highest reported for molecular Mo‐based DODH catalysts. A number of experiments aimed at providing insight in the reaction mechanism of [Cp*MoO2]2O have led to the proposal of a catalytic pathway in which the [Cp*MoO2]2O catalyst reacts with the diol substrate to form a putative nonsymmetric dimeric diolate species, which is reduced in the next step at only one of its Mo‐centers before extrusion of the olefin product. [ABSTRACT FROM AUTHOR]

We report the synthesis, characterization and coordination chemistry of a new naphthyridine-derived phosphinite PONNOP expanded pincer ligand. As envisioned, the dinucleating ligand readily binds two copper(I) centers in close proximity, but undergoes an unexpected rearrangement in the presence of nickel(II) salts to form an interesting PONNP pincer platform. [ABSTRACT FROM AUTHOR]

The synthesis of a well‐defined dicopper carbene complex supported by the PNNP (2,7‐bis(di‐tert‐butylphosphaneyl)methyl‐1,8‐naphthyridine) expanded pincer ligand is reported. This carbene complex is remarkably stable, even in the presence of air and water. The reactivity of this complex was explored towards typical carbene transfer substrates and its electronic structure was investigated. Using a combination of experiments and DFT calculations, the principles that underly the stability of dinuclear carbene complexes are probed. [ABSTRACT FROM AUTHOR]

A naphthyridine‐derived expanded pincer ligand is described that can host two copper(I) centers. The proton‐responsive ligand can undergo reversible partial and full dearomatization of the naphthyridine core, which enables cooperative activation of H2 giving an unusual butterfly‐shaped Cu4H2 complex. [ABSTRACT FROM AUTHOR]

We re-investigated the crystal structure of diaquobis(salicylato)copper(II), CuSal, which is an OD material with disordered layer stacking. The diffraction pattern consists of sharp Bragg spots and diffuse streaks. From the Bragg reflections we determined the ordered part of the structure, which can either be described by an orthorhombic or a twinned monoclinic lattice. The main motif of the structure consists of one-dimensional coordination polymers that are connected by hydrogen bonds into two-dimensional layers. The layer stacking is disordered and from simulations with a Markovian growth models we could fully explain the diffuse streaks of the current structure when the layers are stacked randomly. [ABSTRACT FROM AUTHOR]

The X‐ray crystal structure of tris[N‐(2‐hydroxyethyl)‐2,2′‐iminodiethanolato]tris(2,2′,2′′‐nitrilotriethanolato)tetrairon(II)triiron(III) bis(perchlorate), [Fe7(C6H12NO3)3(C6H13NO3)3](ClO4)2 or [Fe7(tea)3(tea‐H)3](ClO4)2 (tea‐H3 is triethanolamine), is known from the literature [Liu et al. (2008). Z. Anorg. Allg. Chem.634, 778–783] as a heptanuclear coordination cluster. The space group was given as I213 and is reinvestigated in the present study. We find a new space‐group symmetry of Pa and could detect O—H hydrogens, which were missing in the original publication. Consequences on the Fe oxidation states are investigated with the bond‐valence method, resulting in a mixed‐valence core of four FeII and three FeIII centres. Symmetry relationships between the two space groups and the average supergroup Ia are discussed in detail. [ABSTRACT FROM AUTHOR]

The crystal structure of 5-fluorosalicylic acid is known from the literature [Choudhury & Guru Row (2004). Acta Cryst. E 60, o1595-o1597] as crystallizing in the monoclinic crystal system with space-group setting P21/ n and with one molecule in the asymmetric unit (polymorph I). We describe here a new polymorph which is again monoclinic but with different unit-cell parameters (polymorph II). Polymorph II has two molecules in the asymmetric unit. Its structure was modelled as a twin, with a pseudo-orthorhombic C-centred twin cell. [ABSTRACT FROM AUTHOR]

The crystal structure of para-methyl-l-phenylalanine at 230 K resembles that of the para-fluorinated analogue from the literature but is commensurately modulated with seven molecules in the asymmetric unit (Z' = 7). At 100 K, the superstructure loses its modulation, leading to a unit cell with Z' = 1, with clear disorder in the phenyl ring orientations. The methyl-substituent in para-methyl-L-phenylalanine has, in contrast to fluorine, no polar interactions with protons of neighboring molecules, which might allow for the well-defined modulation of the crystal structure at 230 K. [ABSTRACT FROM AUTHOR]

• Consequences of symmetry choice in crystal structure determination. • Detection of wrong space group symmetry. • Validation of crystallographic data quality. We comment on the crystal structure of an enanantipure chiral zinc complex which has been described by Ivanova & Spiteller (2022) erroneously in a centrosymmetric space group with the metal on an inversion center. Subsequent information about thermal motion, octahedral distortion and charge density in their article is highly flawed. [ABSTRACT FROM AUTHOR]

A bulky, tridentate phenolate ligand (ImPh2NNOtBu) was used to synthesise the first example of a mononuclear, facial, N,N,O‐bound iron(II) benzoylformate complex, [Fe(ImPh2NNOtBu)(BF)] (2). The X‐ray crystal structure of 2 reveals that the iron centre is pentacoordinate (τ=0.5), with a vacant site located cis to the bidentate BF ligand. The Mössbauer parameters of 2 are consistent with high‐spin iron(II), and are very close to those reported for α‐ketoglutarate‐bound non‐heme iron enzyme active sites. According to NMR and UV‐vis spectroscopies, the structural integrity of 2 is retained in both coordinating and non‐coordinating solvents. Cyclic voltammetry studies show that the iron centre has a very low oxidation potential and is more prone to electrochemical oxidation than the redox‐active phenolate ligand. Complex 2 reacts with NO to form a S=3/2 {FeNO}7 adduct in which NO binds directly to the iron centre, according to EPR, UV‐vis, IR spectroscopies and DFT analysis. Upon O2 exposure, 2 undergoes oxidative decarboxylation to form a diiron(III) benzoate complex, [Fe2(ImPh2NNOtBu)2(μ2‐OBz)(μ2‐OH)2]+ (3). A small amount of hydroxylated ligand was also observed by ESI‐MS, hinting at the formation of a high‐valent iron(IV)‐oxo intermediate. Initial reactivity studies show that 2 is capable of oxygen atom transfer reactivity with O2, converting methyl(p‐tolyl)sulfide to sulfoxide. [ABSTRACT FROM AUTHOR]

Diels–Alder (DA) cycloaddition of furanics is emerging as a key transformation in circular chemistry, providing access to highly versatile, biobased platform molecules. Further development of this technology into viable industrial applications faces major challenges, a notorious one being the lack of reactivity of the most readily available furans, i.e. the furfural derivatives. Herein we describe the remarkably-facile intramolecular DA reaction of allyl acetals of different furfurals to efficiently afford formal DA adducts with the atypical, unreactive dienophile allyl alcohol. Our methodology gives access to unprecedented oxanorbornene derivatives in high chemo-, regio- and stereoselectivity, which can be readily diversified into valuable products. This offers the potential of scalable production of renewable chemical building blocks from cheap, bioderived platform molecules. [ABSTRACT FROM AUTHOR]

Objective This study aimed to analyze the retention rate of lacosamide ( LCM) in patients with epilepsy and intellectual disabilities ( IDs), to identify factors influencing retention rate, and to investigate the LCM retention rate with and without concomitant sodium channel blocker ( SCB). We hypothesized that the retention rate of LCM with concomitant SCB would be lower than without SCB. Methods Using the Kaplan-Meier estimator, we conducted a monocentric, retrospective, observational, open-label study to evaluate LCM retention rates in patients with IDs and drug-resistant epilepsy. In addition, the impact of therapy-related variables on the long-term retention of LCM was evaluated. Results One hundred thirty-six subjects with IDs and drug-resistant epilepsy were included (age 2-66 years); most patients had focal epilepsy. Long-term retention rates were 62.0% at 1 year, 43.7% at 2 years, and 29.1% at 3 and 4 years. Reasons for LCM discontinuation included insufficient therapeutic benefits (69%), adverse events (11%), or a combination of both factors (8%). The LCM retention rate was influenced by the number of background antiepileptic drugs ( AEDs). An additional and independent influence of concomitant therapy with SCB on retention rate could not be confirmed. Significance One of the major challenges in medically caring for patients with epilepsy and IDs is the high rate of drug resistance. However, there is a lack of evidence-based information about the efficacy and tolerability of AEDs in this population. It has been shown that concomitant SCB use is a key factor in increasing the risk of LCM failure in children with epilepsy. This finding has not been replicated in our predominantly adult sample of patients with IDs. [ABSTRACT FROM AUTHOR]

Iron complexes derived from a bis-isoindoline-bis-pyridine ligand platform based on the BPBP ligand (BPBP= N,N′-bis(2-picolyl)-2,2′-bis-pyrrolidine) have been synthesized and applied in selective aliphatic C−H oxidation with hydrogen peroxide under mild conditions. The introduction of benzene moieties on the bis-pyrrolidine backbone leads to an increased preference of tertiary over secondary C−H bond oxidation (3°/2° ratio up to 33). On the other hand, substituting the meta-position of the pyridines with bulky silyl groups affords enhanced secondary C−H oxidation selectivity and generally leads to higher product yields and mass balances. [ABSTRACT FROM AUTHOR]

The interdependence between religion and economics has received much scholarly attention in recent years. This renewed interest in an old topic has evolved into the economics of religion, an interdisciplinary field of research in the social sciences. Many scholars in this debate argue that religion continues to have a major social impact, particularly in the United states. However, this debate neglected the Amish, a traditional Anabaptist group that is thriving in modern America despite numerous constraints on the use of technology, education, and professional choices. [ABSTRACT FROM AUTHOR]

The selective synthesis of purely organic cages with hetero-sequenced functionalized cavities is demonstrated. The strategy to obtain these compounds is based on a stepwise approach using thermodynamically controlled imine condensations. To accomplish this, the amine building blocks carry additional azide groups, which act as masked amines and enable the synthesis of the desired cavities. This approach offers a precise control of interior functionalization, the substitution pattern and the cage size, which is demonstrated by the selective synthesis of four cages. The largest described cage has been investigated towards its ability for guest encapsulation and is able to selectively encapsulate functionalized arenes that offer a matching substitution pattern. [ABSTRACT FROM AUTHOR]

Introduction: The coronoid is a crucial element for elbow stability. In case of posttraumatic instability or reduced range of motion, a complex reconstruction might be necessary.Case: We present the case of a polytraumatized patient with complex upper extremity injury and initial poor outcome. Subluxation after initial surgery was treated by sublime tubercle reconstruction with a corticocancellous iliac crest graft. Due to massive ossification, the elbow remained stiff and the paraplegic patient was unable to use a manually propelled wheelchair. After arthrolysis, the unstable elbow was treated with an osteocartilaginous graft from the navicular of the foot as well as ulnar and radial collateral ligamentoplasties. At the time of follow-up, the patient had a stable joint and was able to independently perform activities of daily living.Conclusion: An autologous navicular graft seems to be an excellent option for our paraplegic patient as the shape matches the sublime tubercle of the ulna. [ABSTRACT FROM AUTHOR]

The title compound, {[Cu2(C7H4O3)2(H2O)2]·2H2O}n, contains two copper(II) cations in special positions (one on a twofold rotation axis and one on an inversion centre) and the the salicylate ligand in its dianionic form. By four- and six-coordinate metal coordination, chains are formed parallel to [001], which are extended by O--H⋯O hydrogen bonding into sheets extending parallel to (100). These sheets are weakly connected by O--H⋯O hydrogen bonding via the non-coordinating lattice water molecules into a three-dimensional network. [ABSTRACT FROM AUTHOR]

Starting from a chiral furanone, the nitrone-olefin [3 + 2] cycloaddition can be used to obtain bicyclic isoxazolidines for which we report a set of reactions to selectively modify each functional position. These synthetically versatile bicyclic isoxazolidines allowed us to obtain complex glycomimetic building blocks, like iminosugars, via multicomponent chemistry. For example, a library of 20 pipecolic acid derivatives, a recurring motif in various prescription drugs, could be obtained via a one-pot Staudinger/aza-Wittig/Ugi three-component reaction of a bicyclic isoxazolidine-derived azido-hemiacetal. Notably, specific pipecolic acids in this library were obtained via hydrolysis of an unique tricyclic imidate side product of the Ugi reaction. The azido-hemiacetal was also converted into an aza-C-glycoside iminosugar via an unprecendented one-pot Staudinger/aza-Wittig/Mannich reaction. [ABSTRACT FROM AUTHOR]

A strategy is reported for the immobilization of iridium-based water oxidation catalyst 3 onto fluorine-doped tin oxide (FTO) anodes evaluated for the electrocatalytic oxidation of H2O. The strategy is based on noncovalent π-π interactions between multiwalled carbon nanotubes (MWCNTs) and the cationic acetylammonium pyrene moiety (Pyr+) covalently attached to a NHC IrCp*Cl2 catalytically active center (NHC=N-heterocyclic carbene, Cp*=C5Me5). The dispersive properties of the Pyr+ moiety in compound 3 leads to the formation of stable MWCNT dispersions in aqueous solutions. In addition, the MWCNT/ 3 assembly shows activity in the Ce4+-driven oxidation of H2O. FTO/MWCNT/ 3 anodes show increased current densities when used as a working electrode for the electrocatalytic oxidation of H2O. At higher anodic polarizations initially high current densities were achieved; however, these currents prove to be non-sustained due to delamination and degradation of the catalytically active surface. The immobilization strategy is limited to applications below 1.4 V vs normal hydrogen electrode (NHE) as oxidation of the pyrene backbone is evident at higher potentials. [ABSTRACT FROM AUTHOR]

Finding new catalysts for the release of molecular hydrogen from methanol is of high relevance in the context of the development of sustainable energy carriers. Herein, we report that the ruthenium complex Ru(salbinapht)(CO)(P i-Pr3) {salbinapht=2-[({2′-[(2-hydroxybenzyl)amino]-[1,1′-binaphthalen]-2-yl}imino)methyl]phenolato} ( 2) catalyzes the methanol dehydrogenation reaction in the presence of base and water to yield H2, formate, and carbonate. Dihydrogen is the only gas detected and a turnover frequency up to 55 h−1 at 82 °C is reached. Complex 2 bears a carbonyl ligand that is derived from methanol, as is demonstrated by labeling experiments. The carbonyl ligand can be treated with base to form formate (HCOO−) and hydrogen. The nature of the active species is further shown not to contain a CO ligand but likely still possesses a salen-derived ligand. During catalysis, formation of Ru(CO)2(H)2(P- iPr3)2 is occasionally observed, which is also an active methanol dehydrogenation catalyst. [ABSTRACT FROM AUTHOR]

Background and Aim: Hyperextension instability of the metacarpophalangeal (MCP) joint of the thumb may result in pain, malfunction, and accelerated osteoarthritis in the carpometacarpal (CMC) joint. One method of treatment is sesamoid arthrodesis. The aim of this study is to investigate if a sesamoid transfer as a treatment of hyperextension instability of the thumb MCP joint leads to an altered distribution of the subchondral mineralisation and a negative clinical outcome.Methods: Sesamoid transfer was performed on 12 patients with hyperextension instability of the MCP joint of the thumb. The range of motion (ROM) and radiologic outcome were assessed. Pinch and power grip strength were measured and compared to the nonoperated side. To determine the areas of maximum subchondral mineralisation in the joint, computed tomography (CT)-osteoabsorptiometry was performed to determine the long-term stress distribution within the joint.Results: The distributions of the stress zones in the operated and nonoperated thumbs were not statistically different a median of 5 years following the sesamoid transfer procedure. There was no difference in the functional and radiological results between the operated and nonoperated thumbs.Conclusion: If it is assumed that the nonoperated thumb represents the normal condition for each individual, then it may be deduced that the operation achieves good clinical results, and the distribution of the subchondral mineralisation does not change. [ABSTRACT FROM AUTHOR]

The crystal structure of 5-iodouracil, C4H3IN2O2, has been determined in the noncentrosymmetric space group P21 on a nonmerohedrally twinned crystal. Both twin components are enantiomorphically pure, but the twin element is a mirror plane perpendicular to c*. The molecular structure is discussed and stacking faults in the two-dimensional packing are proposed as a reason for the twinning. [ABSTRACT FROM AUTHOR]

Replacing nitrogen by phosphorus in otherwise similar structures changes the properties of the resulting compounds significantly due to the electronic differences that exist between these heteroatoms. While the “hard” nitrogen atom of the pyridine moiety acts as a good σ-donor, the “soft” phosphorus atom of the phosphinine core results in a rather strong π-acceptor capacity. A series of novel group 6 complexes [M(CO)4(L^L)] (M = Cr0, Mo0, W0) have been synthesized, in which L^L is either 2-(2′-pyridyl)-4,6-diphenylphosphinine (P,N) or the corresponding bipyridine derivative, 2-(2′-pyridyl)-4,6-diphenylpyridine (N,N) as a chelating, bidentate ligand. The here presented results describe a detailed investigation of the structural and spectroscopic properties of the coordination compounds [M(CO)4(P,N)] and [M(CO)4(N,N)] (M = Cr0, Mo0, W0), leading to a better understanding of such intriguing aromatic phosphorus heterocycles. [ABSTRACT FROM AUTHOR]

Background: The invention of the locking plate technology leads to alterations of treatment strategies at metaphyseal fracture sites with the concept of spontaneous remodeling of trabecular bone voids. Whereas trabecular regeneration has been proven in experimental animal studies, no histologic data exist on human fracture healing with special emphasis on bone voids. Methods: In order to qualify the trabecular bone remodeling capacity in vivo, bone specimens from the metaphyseal bone void were analyzed 14 months after trauma using quantitative histomorphometry. Twenty-five patients with an unstable dorsally displaced distal radius fracture were fixed with a palmar locking plate without additional bone graft or substitute. At implant removal, specimens from the previous compression void were harvested with a trephine in a volar-dorsal direction. In 16 patients, histomorphometric analysis could be performed, comparing the dorsal trabecular network with the volar, non-compressed ultrastructure. Results: Significant differences for bone volume/total volume (BV/TV), trabecular number (TbN) and trabecular separation (TbSp), but not for trabecular thickness (TbTh) and osteoid volume/total volume (OV/TV), were detected. Neither patient age, defect size nor gender had a significant influence on bone remodeling. Conclusions: The results of this study indicate that trabecular bone remodeling does not lead to pre-trauma bone quality in metaphyseal bone compression voids following reduction and application of a locking plate. [ABSTRACT FROM AUTHOR]

Qualitativ hochwertiges Wohnen im Hochhaus in Großstädten ist nicht nur ein neuer Trend, sondern bezogen auf die Gebäudehülle eine neue Entwicklungsaufgabe. 2014 wurden nie dagewesen viele Wohnhochhaus-Wettbewerbe ausgelobt und zur Weiterplanung entschieden. Dieses Zukunftsthema setzt sich unmittelbar in 2015 fort. Die Wohnhochhaus-Fassade muss im Vergleich zur Bürofassade völlig andere Anforderungen erfüllen. Der Wohnkomfort und auch der täglich erlebbare visuelle Komfort stehen im Vordergrund. Die Wirtschaftlichkeit von neu zu entwickelnden Fassadenkomfortlösungen hat ebenfalls einen sehr hohen Stellenwert, denn die Bauherren und Investoren von Wohnhochhäusern sind nahezu ausnahmslos Projektentwickler. High-rise residential buildings. High quality living in high-rise buildings in big cities is not just a new trend, but concerning the building envelope a new development task. An unprecedented amount of competitions for residential high-rise buildings were set up and a considerable amount of corresponding buildings have been built in 2014. This continues unrelentingly in 2015. The residential skyscraper facade must meet completely different requirements compared to office facades. Personal, thermal and visual comfort are paramount. As Clients for these kind of buildings are almost without exception Developers and Investors the cost-effectiveness of newly developed facade solutions has a very high priority. [ABSTRACT FROM AUTHOR]

Theformation of a bisMETAMORPhos PN-bridged dimeric PdIcomplex(3) from ligand 1and Pd(dba)2is described. The addition of 1to Pd(dba)2initially leads to the formation of Pd0complex 2, which has a highly distorted tetrahedral environment andbinds two neutral ligands 1. Complex 2convertsto {PdI}2complex 3upon heating.Complex 3consists of a completely flat Pd–Pdcore, with a Pd–Pd bond length of 2.6199(4) Å, and thePd centers display a highly distorted square planar coordination environment.The formation of complex 3from 2is suggestedto proceed via an in situcomproportionation pathway.Initial decoordination of one ligand from 2followedby oxidative addition of one neutral coordinated ligand arm leadsto a 1-PdIIH complex. Insertion of free dbainto the Pd–H bond generates a 1-PdIIdba complex that releases 1,5-diphenylpent-1-en-3-one via intra-or intermolecular protonolysis. Concomitantly, comproportionationwith 1-Pd0yields 3. Complex 3was found to function as a precatalyst in the Suzuki–Miyauracross-coupling of p-chloroacetophenone with goodconversions. [ABSTRACT FROM AUTHOR]

The encounter complex, i.e. , the pre-organized assembly consisting of a Lewis acid and a Lewis base, is a fundamental concept in frustrated Lewis pair (FLP) chemistry. However, this donor–acceptor complex is challenging to study due to its transient nature. Here, we present a combined theoretical and experimental investigation on the potential isolation of an encounter complex enabled by enhancement of London dispersion forces between a sterically encumbered Lewis acid and base pair. Guided by computational analyses, the FLP originating from the bulky triarylamine N(3,5- t Bu2 C6 H3)3 and the novel triarylborane B(3,5- t Bu2 C6 H3)3 was investigated, leading to the isolation of a 1:1 co-crystal of both FLP components. [ABSTRACT FROM AUTHOR]

Multinuclearmagnesium hydride complexes react with pyridine, forming1,2- and 1,4-dihydropyridide (DHP) complexes. Reaction of PARA3Mg8H10with pyridine initiallyformed 1,2-DHP and 1,4-DHP product mixtures which converted at 60°C into PARA-[Mg(1,4-DHP)]2·(pyridine)2(PARA= [(2,6-iPr2C6H3)NC(Me)C(H)C(Me)N]2-(p-C6H4)). Reaction of [NN-(MgH)2]2with pyridine gave exclusive formationof the 1,2-DHP product NN-[Mg(1,2-DHP)]2·(pyridine)2(NN= [(2,6-iPr2C6H3)NC(Me)CHC(Me)N−]2).Both products were characterized by crystal structure determinations.The unusual preference for 1,2-addition is likely caused by secondaryintramolecular interactions based on mutual communication betweenthe metal coordination geometries: an extended network of C–H···Cπ-interactions and π-stacking interactions is found. Whereas PARA3Mg8H10is hardly activein magnesium-catalyzed hydroboration of pyridines with pinacolborane,[NN-(MgH)2]2shows efficient coupling.However, the regioselectivity of the stoichiometric reaction is nottranslated to the catalytic regime. This result is taken as an indicationfor a potential alternative mechanism in which magnesium hydride intermediatesdo not play a role but the hydride is transferred from an intermediateborate complex. [ABSTRACT FROM AUTHOR]

A series of organometallic 4,4'-substituted benzylidene aniline complexes 4-ClPt-3,5-(CH2NMe2)2C6H2CH=NC6H4R'-4', abbreviated as PtCl[NCN(CH=NC6H4R'-4')-4], with R' = NMe2, Me, H, Cl, CN (1-5, respectively), was synthesized via a Schiff-base condensation reaction involving reaction of PtCl[NCN(CH=O)-4] (7) with the appropriate 4-R'-substituted aniline derivative (6a-e) in toluene. The resulting arylplatinum(II) products were obtained in 75-88% yield. Notably, product 2 was also obtained in 68% yield from a reaction in the solid state by grinding solid 7 with aniline 6b. The structures of 2, 4, and 5 in the solid state (single crystal X-ray diffraction) showed a non-planar geometry, in particular for compound 5. The electronic interaction between the donor benzylidene fragment PtCl(NCN-CH) and the para-R' aniline substituent through the azomethine bridge was studied with NMR and UV/Vis spectroscopy. Linear correlations were found between the azomethine ¹H, the 195Pt NMR and various 13C NMR chemical shifts, and the substituent parameters sF and sR of R' at the aniline site. In common with organic benzylidene anilines, the azomethine ¹H NMR chemical shift showed anomalous substituent behavior. The 195Pt NMR chemical shift of the platinum center can be used as a probe for the electronic properties of the delocalized p-system of the benzylidene aniline framework, to which it is connected. The dual substituent parameter treatment of the azomethine 13C NMR shift gave important insight into the unique behaviour of the Pt-pincer group as a substituent. Inductively, it is a very strong electron-withdrawing group, whereas mesomerically it behaves like a very strong electron donating group. [ABSTRACT FROM AUTHOR]

We describe the synthesis of a range of novel iminobisphosphine ligands based on a sulfonamido moiety [R1SO2N=P(R2)2-P(R3)2]. These molecules rearrange in the presence of nickel by metal-induced breakage of the P-P bond to yield symmetrical and nonsymmetrical diphosphinoamine nickel complexes of general formula Ni{[P(R2)2]N(SO2R1)P(R3)2}Br2. The complexes can be isolated and are very stable. Upon activation by MAO, these complexes oligomerise ethylene to small chain oligomers (mainly C4-C8) with high productivity. Surprisingly fast codimerisation reactions of ethylene with butenes is observed, leading to a high content of branched C6 products. [ABSTRACT FROM AUTHOR]

Self-assembled Cu-based coordination polymers derived from thiophene-2,5-dicarboxylic acid (Cu-TDC) and furan-2,5-dicarboxylic acid (Cu-FDC) were synthesized via a solvothermal method and their H2 adsorption behaviour was investigated and contrasted with isophthalic acid (Cu-m-BDC) and terephthalic acid (Cu-BDC) derivatives. Both heterocyclic-based coordination polymers exhibit low surface areas (<300 m² g-1) upon activation but unusually high isosteric heats of hydrogen adsorption (7.5-9.2 kJ mol-1). Hydrogen uptake values of 0.64-0.75 wt% (77 K and 1 bar) were recorded and these high uptake values are attributed to the optimal pore size (5.4-8 Å) and the polarizability of the 5-membered heterocycles. [ABSTRACT FROM AUTHOR]

The development of a novel set ofcomplexes bearing an NHC-amineligand (CNHC-NH2) is described. M(cod) complexes(M = Ir, Rh) and a Ru complex have been synthesized in which threedifferent coordination modes of the ligand were established: monodentate,neutral bidentate, and anionic bidentate. The anionic bidentate coordinationmode of the anionic CNHC-NH–ligand arisesfrom deprotonation of the amine moiety of the neutral CNHC-NH2ligand. Ligand deprotonation proved to be reversiblefor the Rh and Ir complexes, as was shown by subsequent treatmentof the complexes with base and acid. The structural parameters ofthese differently coordinated ligands were examined, and it was shownthat the conjugation of the aniline ring plays a major role in determiningthe ligand properties. Structural parameters derived from DFT calculationsconfirm delocalization of the anionic charge over the ligand framework,as is clear from a comparison of the (hypothetical) neutral bidentatecomplexes [M(cod)(κ2C,N-{CNHC-NH2})]숫 those of the(synthesized) monoanionic complexes [M(cod)(κ2C,N-{CNHC-NH})] (M = Rh, Ir).A similar trend in the structure and bond lengths of the aniline ringswas found in the solid-state structure of the novel dimeric complex[(Ru(κ2C,N-{CNHC-NH})(κ2C,N-{CNHC-NH2})Cl)2(μ-Cl)](PF6). The octahedral d5ruthenium(III) centers inthis complex both contain a neutral bidentate CNHC-NH2ligand as well as an anionic bidentate CNHC-NH–ligand. Quite remarkably, the complex is diamagnetic,arising from antiferromagnetic coupling of the two low-spin ruthenium(III)centers over the chloride linker. DFT calculations indeed confirmthat the open-shell singlet electronic structure is most stable. [ABSTRACT FROM AUTHOR]

Thesynthesis of a series of pyridine-based PNP-pincer rhenium-oxocomplexes, with phenyl (1, 3), tert-butyl (2), or cyclohexyl (4) groups onthe phosphorus atoms and either a ReO2X (1, 2) or a ReCl2O (3, 4) core is reported. The structures of these compounds were characterizedusing 1H, 13C, and 31P NMR and usingX-ray crystallography for 1and 4. Compounds 2and 3crystallize as the corresponding ReO(OH)Xcompounds upon their reaction with moisture during the crystallizationprocess. The complexes were tested as catalysts in the oxidation reactionof limonene with H2O2, the oxygen atom transferreaction from pyridine N-oxide to triphenylphosphine,and the dehydration reaction of 1-phenylethanol, but all showed poorcatalytic performance. All complexes can be deprotonated at the benzylicarm, and 2can be deprotonated twice, accompanied bydearomatization of the pyridine ring. 3and 4are highly stable in their oxidized forms. The noninnocent behaviorshown here could open up possibilities for cooperative catalysis. [ABSTRACT FROM AUTHOR]

The title compound, [(C2H5)4N][FeCl4], has at room temperature a disordered structure in the high-hexagonal space group P63 mc. At 230 K, the structure is merohedrally twinned in the low-hexagonal space group P63. The volume has increased by a factor of 9 with respect to the room-temperature structure. At 170 and 110 K, the structure is identical in the orthorhombic space group Pca21 and twinned by reticular pseudomerohedry. The volume has doubled with respect to the room-temperature structure. All three space groups, viz. P63 mc, P63 and Pca21, are polar and the direction of the polar axis is not affected by the twinning. In the P63 and Pca21 structures, all cations and anions are well ordered. [ABSTRACT FROM AUTHOR]

Der größte Wachstumsmarkt der Welt sichert dem Exportland Deutschland eine anhaltende Wirtschaftsstabilität. 50 % des Weltbauvolumens der nächsten 10 bis 15 Jahre werden in China realisiert. Der Bauboom setzt sich in den uns weitgehend unbekannten 20 bis 30 'Kleinstädten' mit 5 bis 10 Millionen Einwohnern fort. Eine Chance für deutsche Architektur- und Engineering-Büros. Der Beitrag zeigt auf, welche Chancen der chinesische Fassaden- und Glasbaumarkt bietet, ebenso was in China möglich ist und was nicht möglich ist, dies sowohl theoretisch als auch anhand von geplanten Beispielprojekten in China. Facades, glass construction in China. The world's largest emerging market secures a lasting stability for Germany's export economy. 50 % of the global construction activity of the coming 10 to 15 years will take place in China. The construction boom continues in the 20 to 30 'smaller cities' with 5 to 10 million inhabitants which are commonly unknown to us. This represents a chance for German architecture and engineering practices. The article outlines the chances which lie within the Chinese facade- and glass construction market and furthermore shows what is possible or impossible, in theory as well as by referring to practical examples of current design projects in China. [ABSTRACT FROM AUTHOR]

The synthetic scope of proton-responsive sulfonamidophosphorus (METAMORPhos) ligands is expanded and design principles for the selective formation of particular tautomers, ion pairs, or double condensation products are elucidated. These systems have been introduced in the coordination sphere of Ru for the first time, thereby enabling the exclusive coordination as a monoanionic P,O chelate. Depending on the Ru precursor, halide-bridged dinuclear species 3- 5 or cymene-derived piano-stool complexes 6- 9 are isolated. The METAMORPhos framework is shown to play a role in the heterolytic cleavage of H2, with species 7 converted into neutral monohydride 10. Substitution chemistry with cymene complex 7 has also been examined, thereby giving rise to tetrakis(acetonitrile) adduct 11. Introduction of a second equivalent of METAMORPhos ligand to this species yielded the bis(ligated) derivative 13, for which variable-temperature (VT) NMR spectroscopy indicates coalescence of the phosphine donors at high temperature. Solid-state structures of 3, 6, 11, and 13 are presented to establish the precise bonding situation of the inorganic PNSO framework within METAMORPhos upon coordination as a proton-responsive monoanionic P,O chelate. [ABSTRACT FROM AUTHOR]

Copper complex formation of JosiPhos-type ligands leads to extreme differences in solubility between the racemate and the enantiomers. [ABSTRACT FROM AUTHOR]

A study of the influence of reaction conditions on the Pd/TOMPP-catalyzed (TOMPP = tris(2-methoxyphenyl)phosphine) telomerization of 1,3-butadiene with phenols revealed that the composition of the reaction medium strongly influences the regioselectivity of the telomer products. Mechanistic studies show this effect to be related to the stability of the key catalytic intermediate cis-[Pd((1-3η)-octa-2,7-dien-1-yl)(TOMPP)2]+ (E), which mainly depends on the solvent composition. The crotyl analogue cis-[Pd((1-3η)-but-2-en-1-yl)(TOMPP)2]BF4 (4) was synthesized as a model for E and was fully characterized, including by an X-ray crystal structure determination. Comparison of the crystal structures of 4 and [Pd((1-3,7,8η)-octa-2(E),7-dien-1-yl)(TOMPP)]BF4 (1), an analogue of intermediate C, shows that the difference in regioselectivity for nucleophilic attack of these complexes is not reflected in the structure of the allyl moiety. Furthermore, Pd/TOMPP-catalyzed n/iso equilibration reactions of telomers show that all product formation routes in the Pd-catalyzed telomerization mechanism are reversible. Telomer product equilibration studies resulted in complete conversion to 1,3,7-octatriene, with the selectivity changing over time in favor of formation of the Z isomer of octatriene. [ABSTRACT FROM AUTHOR]

The effect of strain on core–shell MOFcore@MOFshell particles is discussed and compared with that observed for analogous Janus particles. Whereas Janus particles do not display any effect of strain, the core of fully coated core–shell particles collapsed upon the formation of the outer shell, leaving the core inaccessible for guest adsorption. This suggests that Janus particles might become ideal candidates for gas separation, while core–shell particles could play a key role in sequestration of guest molecules. [ABSTRACT FROM AUTHOR]

Self‐sorting species: Nonlinear effects are observed in asymmetric hydrogenation reactions if self‐sorted dinuclear complexes are generated. The nature of the substrate also influences this effect, because it affects the solubility of racemic self‐sorted homochiral dinuclear complexes (see scheme). [ABSTRACT FROM AUTHOR]

Das Dreischeibenhaus in Düsseldorf darf zweifelsfrei als Ikone bezeichnet werden. Das weltberühmte Architekturdenkmal ist nicht nur in der Branche bekannt. Bisherige Versuche, Ideen für eine wirtschaftliche Komplettsanierung des seit Auszug von Thyssen Krupp im Jahre 2010 leer stehenden Hochhauses zu entwickeln, blieben erfolglos. Der Schlüssel hierzu ist die denkmalgeschützte Fassade. Nach dem Erwerb der Immobilie durch die Hamburger MOMENI Gruppe und Black Horse Investments setzen wir gemeinsam mit HPP Architekten und Witte Projektmanagement eine neue, sehr kostengünstige Idee in die Realität um. Die denkmalgeschützte Fassade bleibt erhalten, eine neue Fassade wird innen zwischen die Rohbaudecken eingesetzt. Die zukünftigen Nutzer profitieren von dem hohen Komfort. Denkmalschutz und Projektentwickler sind hochzufrieden. The Three Slice Building Düsseldorf, the Landmark. The Three Slice Building in Düsseldorf is, without doubt, an historic monument with an iconic effect, and is certainly well known to Architects and throughout the entire building and design sector. During the last few years the building was not rented out. In this period, there were some unsuccessful attempts to find ideas, to develop a complete economic refurbishment. The key to such a renovation is certainly the listed facade. After the purchase of the object by the Hamburg based developer MOMENI-Group/Black Horse Investments we are implementing a new, very inexpensive idea into reality in cooperation with HPP architects/Witte Project Management. The existing facade will not be removed but will be subject to only minor modifications. An additional facade will be inserted within the building with a minimum offset to the existing facade allowing for the implementation of highly efficient sun shades within the naturally ventilated facade cavity. Future users will benefit from the high comfort level. Both Monument Preservation officials and developer are highly satisfied. [ABSTRACT FROM AUTHOR]

Abstract: Single crystal X-ray diffraction reveals that 4,4′-bis(tetrahydrothiopyranyl) crystallizes in an equatorial–equatorial geometry with a gauche conformation along the central carbon–carbon bond. B3LYP/6-311G** and MP2/6-311G** calculations show that the antiperiplanar conformation is higher in energy than the gauche one because of sulfur induced stretching and widening of the cyclohexane-like rings. Calculations at various levels of theory suggest that in the antiperiplanar region the twisting coordinate of 4,4′-bis(tetrahydrothiopyranyl) exhibits a very shallow double-well potential. The gauche molecular structure of 4,4′-bis(tetrahydrothiopyranyl) thwarts efficient packing of its molecules in the solid state. [Copyright &y& Elsevier]