“My biggest motivation is the cooperation with bright young students … My favorite pieces of research are the papers of Woodward and Hoffmann on the conservation of orbital symmetry … ” Find out more about Christoph Schneider in his Author Profile.
Tue Aug 11, 2020 13:00
The synthesis and characterization of atomically precise one‐dimensional diradical peripentacene polymers on a Au(111) surface is reported. By means of high‐resolution scanning probe microscopy complemented by theoretical simulations, evidence of their magnetic properties is provided, which arise from the presence of two unpaired spins at their termini. Abstract We report on the synthesis and characterization of atomically precise one‐dimensional diradical peripentacene polymers on a Au(111)...
Tue Aug 11, 2020 13:00
A bifunctional 3d‐metal catalyst for the cascade synthesis of diverse pyrroles from nitroarenes is presented. The optimal catalytic system Co/NGr@SiO 2 ‐L is obtained by pyrolysis of a cobalt‐impregnated composite followed by subsequent selective leaching. In the presence of this material, (transfer) hydrogenation of easily available nitroarenes and subsequent Paal‐Knorr/Clauson‐Kass condensation provides >40 pyrroles in good to high yields using dihydrogen, formic acid, or a CO/H 2 O mixture...
Tue Aug 11, 2020 13:00
Intramolecular halogen boding promotes the intersystem crossing rate in organic molecules and enhances the afterglow efficiency up to 52.1 %. This is the highest value achieved in molecular crystals reported so far. Abstract Ultralong organic phosphorescence (UOP) has attracted increasing attention due to its potential applications in optoelectronics, bioelectronics, and security protection. However, achieving UOP with high quantum efficiency (QE) over 20 % is still full of challenges due...
Tue Aug 11, 2020 13:00
FePO4 nanospheres consisting of mesoporous nanoyolks supported inside robust porous nanoshells are synthesized by a judicious multi‐step templating strategy using carbon nanospheres as the starting material. Their architecture and composition allow these hierarchical FePO4 yolk–shell nanospheres to manifest excellent sodium storage performance as a cathode material for sodium‐ion batteries. Abstract Amorphous iron phosphate (FePO4) has attracted enormous attention as a promising cathode...
Tue Aug 11, 2020 13:00
A density‐based technique —magnetic levitation (MagLev)—developed and used to solve problems in the fields of chemistry, materials science, and biochemistry is described in this Review. MagLev has two principal characteristics: i) it is density‐based, and thus in principle applicable to all materials, and ii) it is simple—a characteristic that makes it useful for a number of applications. Abstract All matter has density. The recorded uses of density to characterize matter date back to as...
Tue Aug 11, 2020 13:00
Strong and stable : A designed dipeptide with azide and alkyne groups at its termini crystallizes in an anticipated topology with the molecules pre‐organized in a topochemically reactive arrangement. Upon heating, it undergoes a single‐crystal‐to‐single‐crystal topochemical azide–alkyne cycloaddition polymerization to yield a 1D polymer with a twist‐stacked layered topology. Abstract To synthesize a fully organic 1D polymer in a novel twist‐stacked topology, we designed a peptide monomer...
Tue Aug 11, 2020 13:00
Aiming for synthetic diversity and simplification of the synthesis, a generic ionothermal approach for imide‐linked covalent organic frameworks has been developed. By using ZnCl2 and eutectic salt mixtures, highly crystalline COFs were synthesized with a significantly reduced reaction time of 10 hours. Unlike common solvothermal methods this approach does not require soluble precursor molecules. Abstract Covalent organic frameworks (COFs) are an extensively studied class of porous materials,...
Tue Aug 11, 2020 13:00
PST‐24, a medium‐pore zeolite with a disordered arrangement of double 5‐ring (d5r ) units, has been synthesized under excess fluoride conditions. Its three ordered polytypes have different channel dimensionalities, depending on the d5r arrangement order. Abstract Herein we report the synthesis, structure solution, and catalytic properties of PST‐24, a novel channel‐based medium‐pore zeolite. This zeolite was synthesized via the excess fluoride approach. Electron diffraction shows that...
Tue Aug 11, 2020 13:00
The chiral recognition mechanism of a family of chiral metal–organic materials was investigated towards the resolution of three racemic mixtures of phenylpropanol. X‐ray single‐crystal analysis of host–guest interactions revealed the specific binding sites with shape complementarity between the guest molecules and the adaptable chiral cavity. Abstract To gain insight into chiral recognition in porous materials we have prepared a family of fourth generation chiral metal–organic frameworks...
Tue Aug 11, 2020 13:00
Bromine atoms are redox by‐products of the Ullmann cross‐coupling reaction on Cu(110) surfaces. They are fundamental for the formation of conductance channels through the pores of a metal–organic network and critically control the channel length. Abstract Efficiency in charge‐transport is a fundamental but demanding prerequisite to allow better exploitation of molecular functionalities in organic electronics and energy‐conversion systems. Here, we report on a mechanism that enables a one‐dimensional...
Tue Aug 11, 2020 13:00
Droplets controlled, polymorphism achieved : Ion‐cluster‐rich droplets formed through liquid–liquid phase separation trigger the nucleation and growth of multicomponent co‐assembly. Manipulating the intermolecular interactions within the droplets can yield co‐assembly polymorphism and tunable phase‐transition behaviors. Abstract Understanding and controlling multicomponent co‐assembly is of primary importance in different fields, such as materials fabrication, pharmaceutical polymorphism,...
Tue Aug 11, 2020 13:00
V for Vanadium : A drastic decrease in cytotoxicity of a mixed‐ligand VV complex 1 after its decomposition in biological media can be employed in intratumoral injections, particularly for brain cancer. The release of relatively non‐toxic V decomposition products into the blood is expected to reduce the side effects and may also be beneficial due to the known neurostimulatory properties of V. Abstract The chemistry and short lifetimes of metal‐based anti‐cancer drugs can be turned into...
Tue Aug 11, 2020 13:00
Hypoxia is a parameter related to many diseases. Ratiometric hypoxia probes often rely on a combination of an O 2 ‐insensitive fluorophore and an O 2 ‐sensitive phosphor in a polymer matrix, which are comprised by high cost and multi‐step synthesis of transition metal complexes. The two‐chromophore hypoxia probes encounter unfavorable energy transfer processes and different stabilities of the chromophores. Reported herein is a pure organic ratiometric hypoxia nanoprobe, assembled by a monochromophore,...
Mon Aug 10, 2020 22:41
A more thorough investigation of the gold(I)‐catalyzed haloalkynylation of arylalkynes was conducted. 13C‐Labeling experiments and quantum chemical calculations reveal a hitherto overlooked intermediate, namely the cyclopropenylmethyl cation. Consideration of this intermediate should facilitate the development of new synthetic methods for the construction of larger cyclic conjugated enyne systems. Abstract The last years have witnessed many gold‐catalyzed reactions of alkynes. One of the...
Mon Aug 10, 2020 22:28
Magnetically induced alignment in NMR can be used as a convenient way to determine the configuration of small molecules. C. Griesinger et al. show in their Communication (DOI: https://doi.org/10.1002/anie.20200488110.1002/anie.202004881) how the necessary anisotropic NMR data can be acquired exploiting the molecule's anisotropic magnetic susceptibility. This approach is demonstrated on the novel natural product gymnochrome G, which was isolated from a deep‐sea crinoid. Cover Illustration: A. Savastano....
Mon Aug 10, 2020 22:28
Physical separations can be superior to chemical separations when it comes to energetics and kinetics, especially when ideal sieving is feasible among hard‐to‐separate gas mixtures. Unfortunately, for industrial gases a very precise pore window size which must be ultramicroporous is needed for ideal sieving. In their Research Article (DOI: https://doi.org/10.1002/anie.20200641410.1002/anie.202006414), Y. Huang, M. J. Zaworotko et al. describe a new variant of Ca‐trimesate that offers just the right...
Mon Aug 10, 2020 22:28
Previously described Lewis superacids are moisture sensitive and predominantly hard in character – features that are severely limiting their widespread use in orbital controlled reactions and under non‐inert conditions. Herein, we describe adducts of bis(perchlorocatecholato)germane, the first hard and soft Lewis superacid based on germanium. Remarkably, the synthesis of this compound is performed in water, and the obtained H 2 O‐adduct constitutes a strong Brønsted acid. If applied as adduct with...
Mon Aug 10, 2020 22:00
A wide range of tunability in physical parameters of a semiconductor used for X‐ray detection is desirable to achieve targeted performance optimization. However, in a dense‐phase semiconductor, fine‐tuning one parameter often leads to unwanted changes in other parameters. Herein, the intrinsic openness in an open‐framework semiconductor has been proven for the first time to be a key structural factor that weakens the mutual exclusivity of the adjustable physical parameters owing to a non‐linear control...
Mon Aug 10, 2020 21:17
DNAzymes are widely used as functional units for creating DNA‐based sensors and devices. Switching of DNAzyme activity by external stimuli is of increasing interest. Herein we report a Cu II ‐responsive DNAzyme rationally designed by incorporating one of the most stabilizing artificial metallo‐base pairs, a Cu II ‐mediated carboxyimidazole base pair ( Im C –Cu II – Im C ), into a known RNA‐cleaving DNAzyme. Cleavage of the substrate was suppressed without Cu II , but the reaction proceeded...
Mon Aug 10, 2020 20:08
Developing a facile controllable avenue to selective semihydrogenation of alkynes to alkenes with a defined configuration using a cheap and safe hydrogen donor is highly desirable, but remains a big challenge. Here, we reported a selective semihydrogenation (deuteration) of numerous terminal and internal alkynes using H 2 O (D 2 O) as the H (D) source over a Pd‐P alloy cathode at a lower potential. Density functional theory (DFT) calculation revealed that the doping of P caused the enhanced specific...
Mon Aug 10, 2020 19:38
By virtue of the unique feature of Shewanella oneidensis MR‐1 ( S. oneidensis MR‐1) that anaerobically catabolize lactate through transferring electrons to metal minerals for respiration, a lactate‐fueled biohybrid (Bac@MnO 2 ) here is constructed by modifying manganese dioxide (MnO 2 ) nanoflowers on the S. oneidensis MR‐1 surface. The biohybrid Bac@MnO 2 assigns decorated MnO 2 nanoflowers as electrons receptor and tumor metabolite of lactate as electrons donor to build complete bacteria...
Mon Aug 10, 2020 17:40
Spontaneously blinking dyes eliminated the requirements of intense laser irradiations and additives to induce fluorophore blinking and greatly facilitated single‐molecule localization microscopy (SMLM) in live‐cell super‐resolution imaging. While the spontaneously blinking had been demonstrated via the thermally induced spirocyclization equilibrium of rhodamines, the stringent requirement on this equilibrium sets a formidable obstacle for the creation of multi‐colored spontaneously blinking rhodamines....
Mon Aug 10, 2020 17:39
Phenylfuropyridone natural products from fungi exhibit a range of antibacterial and cytotoxicity activities, and can potentiate azole antifungals. Herein, we report the concise biosynthetic pathway of compounds in the citridone family through heterologous reconstitution of the pfp pathway. We demonstrate multiple members of this family can be accessed from a reactive ortho‐ quinone methide (QM) intermediate through electrocyclization, cycloisomerization or conjugated addition. Formation of the...
Mon Aug 10, 2020 16:45
The fusion and fission behaviors of exosomes are essential for the cell‐to‐cell communication. Developing exosome‐mimetic vesicles with such behaviors is of vital importance, but still remains a big challenge. Herein, we present an artificial supramolecular vesicle that exhibits redox‐modulated reversible fusion‐fission functions. These vesicles tend to fuse together and form large‐sized vesicles upon oxidation, while undergo a fission process and return to small‐sized vesicles through reduction....
Mon Aug 10, 2020 16:44
The amination of racemic alcohols to produce enantiopure amines is an important green chemistry reaction for pharmaceutical manufacturing, requiring simple and efficient solutions. Here we developed a novel concept and the simplest system for ADH‐TA‐catalyzed cascade reaction to aminate racemic alcohols, which utilizes an ambidextrous ADH to oxidize a racemic alcohol, an enantioselective transaminase to convert the ketone intermediate to chiral amine, and isopropylamine to recycle PMP and NAD +...
Mon Aug 10, 2020 13:44
A general and direct synthesis of dicarboxylic acids including industrially important adipic acid by palladium‐catalyzed dicarbonylation of allylic alcohol is reported. Specifically, the combination of PdCl2 and a bisphosphine ligand (HeMaRaphos) promotes two different carbonylation reactions with high activity and excellent selectivity.
Mon Aug 10, 2020 12:12
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