(‐)‐Finerenone is a nonsteroidal mineralocorticoid receptor antagonist currently in phase III clinical trials for the treatment of chronic kidney disease in type 2 diabetes. It contains an unusual dihydronaphthyridine core. Herein, we report a 6‐step synthesis of (‑)‐Finerenone which features an enantioselective partial transfer hydrogenation of a naphthyridine using a chiral phosphoric acid catalyst with a Hantzsch ester. The process is complicated by the fact that the naphthyridine exists as a...
Sat Sep 05, 2020 21:55
Metal halide perovskites have been widely applied in optoelectronic fields, but their poor stability hinders their actual applications. Here, a perovskite‐zeolite composite was synthesized via in situ growth in air based on aluminophosphate AlPO‐5 zeolite crystals and perovskite nanocrystals. The zeolite matrix provides quantum confinement for perovskite nanocrystals achieving efficient green emission, and passivates the defects of perovskite by H‐bonding interaction leading to longer lifetime...
Sat Sep 05, 2020 17:54
Cobalt(II) alkyl complexes supported by a monoanionic NNN pincer ligand are pre‐catalysts for the regioselective hydroboration of terminal alkynes, yielding the Markovnikov products with α:ß‐(E) ratios of up to 97:3. A cobalt(II) hydride and a cobalt(II) vinyl complex appear to determine the main reaction pathway. In a background reaction the highly reactive hydrido species specifically converts to a coordinatively unsaturated cobalt(I) complex which was found to re‐enter the main catalytic cycle...
Sat Sep 05, 2020 16:31
Photoacoustic agents have been of vital importance for improving the imaging contrast and reliability against self‐interference from endogenous substances. Herein, we synthesized a series of thiadiazoloquinoxaline (TQ)‐based semiconducting polymers (SPs) with a broad absorption covering from NIR‐I to NIR‐II regions. Among them, the excited s‐BDT‐TQE, a repeating unit of SPs, shows a large dihedral angle and narrow adiabatic energy as well as low radiative decay, attributing to its strongly electron‐deficient...
Sat Sep 05, 2020 16:29
The electronic structure of the Au 2 + cation is essential for understanding its catalytic activity. We present the optical spectrum of mass‐selected Au 2 + measured via photodissociation spectroscopy. Two vibrationally resolved band systems are observed in the 290‐ 450 nm range (at ~440 and ~325 nm), which both exhibit rather irregular structure indicative of strong vibronic and spin‐orbit coupling. The experimental spectra are compared to high‐level quantum chemical calculations at the CASSCF‐MRCI...
Sat Sep 05, 2020 12:02
Matching of symmetry at interfaces is a fundamental obstacle in molecular assembly. Virus‐like particles (VLPs) are important platforms to generate vaccines against pathogenic threats including Covid‐19. However, symmetry mismatch between multimeric antigens and VLP subunits can prohibit vaccine nanoassembly. Here we explore spontaneous amidation to establish principles for coupling VLPs to diverse antigen symmetries. SpyTag003/SpyCatcher003‐mediated decoration enabled efficient VLP conjugation and...
Fri Sep 04, 2020 22:00
Improving the charge transport and reducing the bulk/surface recombination are useful for improving the activity and stability of BiVO 4 for water oxidation. Here we for the first time demonstrate that the photoelectrochemical (PEC) performance of BiVO 4 can be significantly improved using the potentiostatically photo‐polarized test. The co‐catalyst‐free BiVO 4 photoanode achieves a record‐high photocurrent of 4.60 mA cm −2 at 1.23 V RHE with an outstanding onset potential of 0.23 V RHE...
Fri Sep 04, 2020 20:12
A new class of bio‐based and fully degradable block polyesters are pressure‐sensitive adhesives. Bio‐based monomers are efficiently polymerized to make block polyesters with controlled compositions. They show high peel adhesions (4‐13 N cm ‐1 ), controllable storage and loss moduli and are removed by adhesive failure. Their properties compare favorably with commercial adhesives or bio‐based polyester formulations but without need for tackifier or additives.
Fri Sep 04, 2020 20:08
Developing copper‐free catalysts for CO 2 conversion into hydrocarbons and oxygenates is highly desirable for electrochemical CO 2 reduction reaction (CO 2 RR). Herein, we report a cobalt phthalocyanine (CoPc) and zinc‐nitrogen‐carbon (Zn‐N‐C) tandem catalyst for CO 2 RR to CH 4 . This tandem catalyst shows more than 100 times enhancement in CH 4 /CO production rate ratio compared with CoPc or Zn‐N‐C alone. Density functional theory calculations and electrochemical CO reduction reaction...
Fri Sep 04, 2020 20:07
Metal allyl species are versatile intermediates in a number of coupling reactions. However, Rh(III) π‐allyls have been rarely elaborated in the context of asymmetric C‐H functionalization. Reported herein is chiral Rh(III) cyclopentadienyl‐catalyzed enantioselective synthesis of lactams and isochromenes via oxidative [4+1] and [5+1] annulation, respectively, between arenes and 1,3‐enynes. The reaction proceeds via a C‐H activation, alkenyl to allyl rearrangement, and nucleophilic cyclization cascade....
Fri Sep 04, 2020 20:07
Recently π‐d conjugated coordination polymers have received a lot of attention due to their unique material properties, although synthesis of long and defect free polymers remains challenging. Here we introduce a novel on‐surface synthesis of coordination polymers with quinoidal ligand under ultra‐high vacuum conditions, which enables formation of flexible coordination polymers with lengths up to hundreds of nanometers. Moreover, this procedure allows the incorporation of different transition metal...
Fri Sep 04, 2020 18:01
The organocatalytic atroposelective strategy for accessing enantioenriched axially chiral IAN analogues was developed for the first time. A class of novel atropisomeric C2‐arylquinoline skeletons were synthesized with high enantiocontrol via chiral phosphoric‐acid‐catalyzed heteroannulation of in‐situ generated vinylidene ortho ‐quinone methide (VQM) intermediates with ortho ‐aminophenones. The strategy tolerated a broad substrate scope, providing a facile organocatalytic approach to IAN...
Fri Sep 04, 2020 17:59
Although N‐alkenoxyheteroarenium salts have been widely used as umpoled synthons with nucleophilic (hetero)arenes, the use of electron‐poor heteroarenes has remained unexplored. To overcome the inherent electron deficiency of quinolinium salts, a traceless nucleophile‐triggered strategy was designed, wherein the quinolinium segment is converted to a transiently activated intermediate, thereby allowing simultaneous C8‐functionalization of quinolines at room temperature. Experimental and computational...
Fri Sep 04, 2020 17:06
A facile molecular structure regulation strategy was exploited to potentially transform the aggregation‐caused quenching (ACQ) chromophore of lipsoluble porphyrin to the aggregation‐induced emission (AIE) active in aqueous phase. By peripheral decoration of 5‐(4‐aminophenyl)‐10,15,20‐triphenylporphyrin (ATPP) with inherent AIE active tetraphenylethene (TPE), a versatile AIEgenic porphyrin derivative (ATPP‐TPE) was obtained, which greatly abolishes the detrimental π‐π stacking and thus surmounts the...
Fri Sep 04, 2020 17:04
Remarkable effects of SiMe 3 , SiEt 3 para ‐substituent in the phenoxide‐modified half‐titanocenes, Cp*TiCl 2 (O‐2,6‐ i Pr 2 ‐4‐R‐C 6 H 2 ) [R = SiMe 3 ( 6 ), SiEt 3 ( 7 )], toward the catalytic activities in ethylene copolymerizations with 2‐methyl‐1‐pentene, 1‐decene, 1‐dodecene and with 9‐decen‐1‐ol (DC‐OH) have been demonstrated. The activities by 6 , 7 at 50 ºC showed higher than those conducted at 25 ºC in all cases in the presence of MAO cocatalyst. Efficient...
Fri Sep 04, 2020 16:29
A novel family of nanocarbon‐based materials were designed, synthesized, and probed within the context of charge‐transfer cascades. In details, we implemented fine‐tuned chains of photo‐ and redox‐active constituents. For the first time, we integrated electron‐donating ferrocenes with light‐harvesting /electron‐donating (metallo)porphyrins and electron‐accepting graphene nanoplates (GNP) into multicomponent conjugates. To control the rate of charge flow between the individual building blocks, we...
Fri Sep 04, 2020 16:28
The fluoronitrenoid metal complexes, FNCoF 2 and FNRhF 2 , as well as the first ternary Rh(VI) and Ir(VI) complexes NIrF 3 and NRhF 3 are described. They were obtained by the reaction of excited group 9 metal atoms with NF 3 , and their IR spectra isolated in solid rare gases (neon and argon) were recorded. Aided by the observed 14/15 N isotope shifts and quantum‐chemical predictions, all four stretching fundamentals of the novel complexes were safely assigned. The F−N stretching frequencies...
Fri Sep 04, 2020 15:34
Subsurface interstitial hydrogen atoms in Pd hydride nanoparticles are directly imaged by using differentiated and integrated differential phase contrast within an aberration‐corrected scanning transmission electron microscope. DFT calculations suggest that the amount and the occupation type of the subsurface hydrogen atoms is indispensable in fine‐tuning the electronic structure and chemical reactivity of the outmost Pd surface. Abstract Resolving interstitial hydrogen atoms at the surfaces...
Fri Sep 04, 2020 12:51
Nickel‐catalyzed linear‐selective hydroarylation of unactivated alkenes with arylboronic acids is demonstrated by a redox‐neutral NiII/NiII catalytic cycle for the first time. This novel catalytic cycle, enabled by the use of an electron‐rich diimine ligand, features broad substrate scope, and excellent functional‐group and heterocycle compatibility under mild reaction conditions in the absence of additional oxidants and reductants. Abstract Reported here is the discovery of a redox‐neutral...
Fri Sep 04, 2020 12:49
We report negative pressure pyrolysis to access dense single metal sites (Co, Fe, Ni etc.) with high accessibility dispersed on 3D graphene frameworks (GFs). Differential pressure inside and outside of metal–organic frameworks promotes cleavage of the derived carbon layers and gradual expansion of mesopores. The 3D GFs possess an enhanced mesoporosity and external surface area, contributing to an excellent oxygen reduction reaction (ORR) activity. Abstract Herein, we report a negative pressure...
Fri Sep 04, 2020 12:48
Tumor‐Triggered Disassembly of a Multiple‐Agent‐Therapy Probe for Efficient Cellular Internalization
A multiple‐agent‐therapy probe based on a peptide‐conjugated‐AIEgen was developed with extracellular MMP‐2 and intracellular CB response. When approaching tumor cells, it can be separated into different agents, which then enter the tumor cells by their dominant pathway with high cellular internalization efficiency and effective multimodal cancer therapy. Abstract Integration of multiple agent therapy (MAT) into one probe is promising for improving therapeutic efficiency for cancer treatment....
Fri Sep 04, 2020 12:47
Ab initio molecular dynamics simulations are used to monitor the evolution of the H‐bond network of water from room temperature to supercritical conditions. The results reveal that the H‐bond oscillation period exceeds the lifetime of H‐bonds in supercritical water by far. Instead, the intermolecular vibrations of water pairs as seen in supercritical water are found to be well represented by isotropic van‐der‐Waals interactions only. Abstract Thinking about water is inextricably linked...
Fri Sep 04, 2020 12:47
A novel route for the production of the versatile chemical building block phthalide from bio‐renewable furfuryl alcohol and acrylate esters is presented. Two challenges that generally limit sustainable aromatics production via Diels‐Alder (DA) aromatization, i.e. an unfavorable equilibrium position and undesired regioselectivity when using asymmetric addends, have been addressed by using a dynamic kinetic trapping strategy. Our strategy involves the use of activated acrylates to speed up both the...
Thu Sep 03, 2020 22:00
Hydrogen‐Bonded Organic Frameworks (HOFs) possess merits such as high porosity, tunable structure, facile modification, and easy regeneration, which, however, have yet to be brought into play for exploring new functional HOF materials. In this study, an electrochromic HOF film was first time reported. The electrophoretic deposition (EPD) method applied here generated a transparent film at room temperature in merely 2 minutes, being facile, efficient, low‐cost, and applicable to other HOFs. The resulted...
Thu Sep 03, 2020 20:35
To design pnictide nonlinear optical materials with wide band gap and large second‐harmonic generation, the heavy halogen I was introduced into pnictides through anionic aliovalent substitution with diamond‐like ZnS as templates. Thus, four excellent halopnictide‐based infrared nonlinear optical crystals, M II 3 PnI 3 (M II =Zn, Cd; Pn=P, As), were obtained. They all exhibited defect diamond‐like structures with highly parallel‐oriented [M II PnI 3 ] mixed‐anionic tetrahedra groups, leading...
Thu Sep 03, 2020 18:29
Structure determination of covalent organic frameworks (COFs) at atomic precision is a bottle‐neck that hinders the development of COF chemistry. Although three‐dimensional electron diffraction (3D‐ED) data has been used to solve structures of sub‐micrometre sized COFs, successful structure solution is not guaranteed as the data resolution is usually low. Herein, we demonstrate that the direct‐space strategy for structure solution, implemented using a genetic algorithm (GA), is a successful approach...
Thu Sep 03, 2020 18:04
A selective and scalable two‐step approach to the dimerization of norbornadiene (NBD) into its thermodynamically most stable dimer, heptacyclo[6.6.0.0 2,6 .0 3,13 .0 4,11 .0 5,9 .0 10,14 ] tetradecane, (HCTD) is reported. Theoretical calculations indicate that the reaction starts with the Rh‐catalyzed stepwise homo Diels‐Alder cyclisation of NBD into its exo‐cis‐endo dimer. Treatment of this compound with acid promotes its evolution to HCTD via a [1,2]‐sigmatropic rearrangement. The assemblies...
Thu Sep 03, 2020 17:59
A new and simple strategy towards electric‐field‐driven multiple chirality switching device has been designed by combining a newly synthesized base‐responsive chiroptical polymer switch ( R‐FLMA ) and p‐benzoquinone ( p‐BQ ) via proton coupled electron transfer (PCET) mechanism. And the semi‐solid device of R‐FLMA has been fabricated successfully. Clear and stable triple chirality states (silence, positive, negative) of this device in visible band can be regulated reversibly (>1,000 cycles)...
Thu Sep 03, 2020 17:04
A mitochondrion‐targeting iridium(III) anthraquinone complex is reported. It is selectively reduced under hypoxic conditions to generate strong turn‐on emission and carbon radicals, achieving in‐vitro and in‐vivo oxygen‐independent photodynamic therapy. Abstract The efficacy of photodynamic therapy is typically reliant on the local concentration and diffusion of oxygen. Due to the hypoxic microenvironment found in solid tumors, oxygen‐independent photosensitizers are in great demand for...
Thu Sep 03, 2020 17:00
The enzyme xylanase from Bacillus circulans (BCX) is involved in the breakdown of xylan, which is one of the most abundant materials in wood. NMR experiments demonstrate that in solution the enzyme is rigid and does not change its structure during turnover. Binding of the substrate occurs in many orientations, including a distorted form. A model is presented for the effect of substrate dynamics on enzyme function. Abstract The single‐domain GH11 glycosidase from Bacillus circulans (BCX)...
Thu Sep 03, 2020 17:00
The oxidation state of Pt single‐atom catalysts (SACs) was controlled from highly oxidized to highly metallic states by reducing Pt single atoms deposited on defective ceria at various temperatures. The optimum oxidation state of the Pt SAC was found for maximizing the catalytic activity for the oxidation of CO, CH4, and NO. Abstract Single‐atom catalysts (SACs) have emerged as promising materials in heterogeneous catalysis. Previous studies reported controversial results about the relative...
Thu Sep 03, 2020 16:59
A method has been developed for the on‐resin preparation of allenamide‐modified peptides, which can subsequently undergo chemoselective thia‐Michael addition with thiols. The approach was shown to be a versatile tool to modify peptides with thiols and to prepare cyclic peptides with excellent conversion (see scheme). Abstract The ability to modify peptides and proteins chemoselectively is of continued interest in medicinal chemistry, with peptide conjugation, lipidation, stapling, and disulfide...
Thu Sep 03, 2020 16:59
A mucus‐penetrating drug‐delivery strategy is designed for the efficient therapy of chronic obstructive pulmonary disease (COPD). After pulmonary aspiration, nanovehicles can penetrate the mucus barrier and adhere onto the mucous membrane. Subsequently, the nanovehicle degrades via the oxidative degradation of BPQDs, releasing the antibiotic amikacin. This suggests that BPQD‐mediated drug release offers a feasible strategy for precision medicine. Abstract Chronic obstructive pulmonary disease...
Thu Sep 03, 2020 16:57
Pt atoms were anchored on RuO2 within RuCeO x by utilizing photogenerated electron transfer between CeO2 and RuO2. The selectively formed Pt‐O‐Ru moieties in the resulting material (Pt/RuCeO x ‐PA) gives a stronger hydrogen spillover effect than randomly loaded Pt complexes, and therefore a higher mass activity and electrochemical stability at high current density. Abstract High‐performance electrocatalysts for the hydrogen evolution reaction (HER) have an important role to play...
Thu Sep 03, 2020 16:57
Designing the polymorph selection system for protein supramolecular assembly and understanding the modulation mechanism at molecular‐level is essential for constructing differentiated functionalized biomaterials with broad potential application. Herein the protein chain relaxation‐crystallization mechanism is developed to control the oriented growth and packing of β‐sheets from amorphous aggregates to crystals at air/water interface. Abstract A promising route to the synthesis of protein‐mimetic...
Thu Sep 03, 2020 16:57
Nikolay Zelinsky was one of the leading chemists worldwide at the beginning of the 20th century. He discovered four reactions that bear his name and his work formed the basis for the petrochemical industry in the Soviet Union. This Essay looks back at his achievements and sets the historical context. Abstract This Essay outlines the life path and scientific achievements of Nikolai Zelinsky to testify to his contributions to organic chemistry, catalysis, and petrochemistry. His legacy includes...
Thu Sep 03, 2020 16:57
Reported herein is a novel Fe‐MoS2 catalyst with Fe atomically dispersed onto MoS2 nanosheets, imitating natural nitrogenase, to boost N2 electroreduction into NH3 at room temperature. The Fe‐MoS2 nanosheets exhibited a faradic efficiency of 18.8 % with a yield rate of 8.63 μg mgcat. −1 h−1 for NH3 at −0.3 V versus the reversible hydrogen electrode. Abstract Efforts have been devoted to achieving a highly efficient artificial synthesis of ammonia (NH3). Reported herein is a novel Fe‐MoS2...
Thu Sep 03, 2020 16:55
NMR spectroscopy was used to characterize the C‐mannose conformation in a thrombospondin repeat using a selective labeling approach. The conformational landscape of the C‐mannose sugar puckers attached to tryptophan residues of the netrin receptor UNC‐5 allows interconversion between the canonical 1C4 state and the B03 / 1S3 state. Abstract Despite the great interest in glycoproteins, structural information reporting on conformation and dynamics of the sugar moieties are limited. We present...
Thu Sep 03, 2020 16:54
Continuous addition of a chemical fuel allows for the autocatalytic formation of surfactant that aggregate into vesicles. These vesicles can be maintained out‐of‐equilibrium by adding a catabolic catalyst to introduce a second, coupled reaction cycle into the metabolic network. Abstract We report chemically fuelled out‐of‐equilibrium self‐replicating vesicles based on surfactant formation. We studied the vesicles’ autocatalytic formation using UPLC to determine monomer concentration and...
Thu Sep 03, 2020 16:54
Molecular vanadium oxides, or polyoxovanadates (POVs) have recently emerged as a new class of molecular energy conversion/storage materials, which combine diverse, chemically‐tunable redox behaviour and reversible multi‐electron storage capabilities. This Review explores current challenges, major breakthroughs, and future opportunities in the use of POVs for energy conversion and storage. The reactivity, advantages, and limitations of POVs are explored with a focus on their use in lithium and post‐lithium...
Thu Sep 03, 2020 15:29
The gold‐catalyzed intermolecular oxyarylation of alkenes is reported. This work employed the oxidative addition of aryl iodides to Me−DalphosAu+ for the formation of a AuIII−Ar intermediate. The better binding ability of alkenes over O nucleophiles ensured the success of intermolecular oxyarylation, giving desired products with a broad substrate scope and high efficiency (>50 examples with up to 95 % yield). Abstract The gold‐catalyzed intermolecular oxyarylation of alkenes is reported....
Thu Sep 03, 2020 14:59
A facile approach to assemble catalase‐like photosensitizing nanozymes with a self‐oxygen‐supplying ability was developed. The process involved Fe 3+ ‐driven self‐assembly of fluorenylmethyloxycarbonyl (Fmoc)‐protected amino acids. By adding a zinc(II) phthalocyanine‐based photosensitizer (ZnPc) and the hypoxia‐inducible factor 1 (HIF‐1) inhibitor acriflavine (ACF) during the Fe 3+ ‐promoted self‐assembly of Fmoc‐protected cysteine (Fmoc‐Cys), the nanovesicles Fmoc‐Cys/Fe@Pc and Fmoc‐Cys/Fe@Pc/ACF...
Thu Sep 03, 2020 14:58
The presence of a small amount of ionic liquid significantly alters the product spectrum of CO2 reduction over a Cu catalyst. The ionic liquid acts as a chemical trapping agent, selectively suppressing the formation of C2+ products that involve carbene as a key intermediate. The response in product distribution to ionic liquid modification offers a new way to disentangle the complex reaction network of CO2 reduction by Cu catalysts. Abstract The key to fully leveraging the potential of...
Thu Sep 03, 2020 14:39
E thylene is the byproduct of olefin metathesis reactions that involve one or more terminal alkenes. Ethylene’s volatility is one reason why many cross‐metathesis or ring‐closing metathesis processes, which are reversible transformations, are efficient. However, because ethylene can be converted to a methylidene complex, which is a highly reactive but relatively unstable species, its concentration can impact olefin metathesis in other ways. In some cases, introducing excess ethylene can increase...
Thu Sep 03, 2020 14:06
Mass transfer of guest molecules has great impact on the applications of nanoporous crystalline materials and particularly the shape selective catalysis over zeolites. Control of mass transfer to alter reaction over zeolites, however, remains an open challenge. Recent studies show that, in addition to intracrystalline diffusion, surface barriers represent another transport mechanism which may dominate the overall mass transport rate in zeolites. Here, we demonstrate the methanol‐to‐olefins (MTO)...
Thu Sep 03, 2020 13:59
Super‐concentrated “water‐in‐salt” electrolytes recently spurred resurgent interest for high energy density aqueous lithium‐ion batteries. Thermodynamic stabilization at high concentrations and kinetic barriers towards interfacial water electrolysis significantly expand the electrochemical stability window, facilitating high voltage aqueous cells. Here we investigated LiTFSI/H 2 O electrolyte interfacial decomposition pathways in the “water‐in‐salt” and “salt‐in‐water” regimes using synchrotron...
Thu Sep 03, 2020 12:0
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