A bis‐acridinium cyclophane incorporating switchable acridinium moieties linked by a 3,5‐dipyridylanisole spacer was studied as a multi‐responsive host for polycyclic aromatic hydrocarbon guests. Complexation of perylene was proven to be the most effective and was characterized in particular by a charge transfer band as signal output. Effective catch and release of the guest was triggered by both chemical (proton/hydroxide) and redox stimuli. Moreover, the dicationic host was also easily switched...
Thu Sep 03, 2020 11:58
Metal nanoparticle surfaces are used for peroxidase‐ and oxidase‐like nanozymes but not for esterase‐like nanozymes. It is challenging to obtain rapid catalytic hydrolysis on a metal surface and even more so without a catalytically labile substrate. Here, we report that metal nanoparticle surfaces rapidly catalyze non‐redox ester hydrolysis in the presence of redox H 3 N–BH 3 (AB). Metal hydrides are readily generated on a Pt nanoparticle (PtNP) from AB, and as a result the PtNP becomes electron‐rich,...
Wed Sep 02, 2020 22:37
In‐depth understanding of electrochemical side reactions is essential for the optimization of new electrode materials or electrochemical cell geometry. The presented MALDI‐MS imaging approach offers a fast and elegant way to detect electrochemical byproducts on the electrode surface and provides additional information about molecular mass and spatial distribution. Abstract Electrochemical side reactions, often referred to as “electrode fouling”, are known to be a major challenge in electro‐organic...
Wed Sep 02, 2020 21:43
Alkylation‐terminated Catellani reactions have not been well developed mainly due to the significant challenge of the transmetalation of β‐H‐containing alkyl groups onto the sterically hindered aryl‐PdII intermediate. In this work, this challenge was overcome by using highly efficient alkyl‐ Ge nucleophiles as terminating reagents. Abstract The Catellani reaction has received substantial attention because it enables rapid multiple derivatization on aromatics. While using alkyl electrophiles...
Wed Sep 02, 2020 21:43
Fibrillar‐transformable peptide‐porphyrin (PWG) nanoparticles activated by the acidic inter‐ and intracellular tumor microenvironment were developed for photodynamic therapy (PDT). The transformation of nanoparticles into nanofibers improved their singlet oxygen generation ability and enabled high accumulation and long‐term retention at tumor sites, resulting in excellent anti‐tumor efficacy via PDT in vivo. Abstract Inspired by the dynamic morphology control of molecular assemblies in...
Wed Sep 02, 2020 21:42
Magnetic and fluorogenic photosensitizer nanoassemblies (NP‐RGD) were constructed via self‐assembly of a cRGD‐ and disulfide‐containing small molecule (1‐RGD). The nanoassemblies allowed the cascade activation of fluorescence/magnetic resonance bimodal imaging and on‐demand photodynamic therapy in the tumor through redox‐driven disassembly and in situ binding with albumin. Abstract Stimuli‐responsive smart photosensitizer (PS) nanoassemblies that allow enhanced delivery and controlled release...
Wed Sep 02, 2020 21:42
Highly chemo‐, regio‐, and enantioselective hydrophosphinylation of alkynes was achieved by using a palladium/Xiao‐Phos catalytic system. This reaction provides enantioenriched P‐chiral alkenylphosphine oxides with broad substrate scope. The secondary phosphine oxides are also recovered with very high ee values through kinetic resolution. Initial mechanistic studies suggest that hydropalladation is likely responsible for the conversion process. Abstract Alkenylphosphine oxides have a wide...
Wed Sep 02, 2020 21:42
A strategy of building compact 2D/2D superlattice films based on molecular ligand‐mediated assembly of colloidal nanosheets is presented. Thanks to their densely packed nature and high stacking ordering, co‐assembled MXene‐rGO laminate films exhibit arguably the highest volumetric energy density ever reported for MXene‐based supercapacitors in aqueous electrolytes. Abstract Inspired by the self‐assembly of nanoparticle superlattices, we report a general method that exploits long‐chain molecular...
Wed Sep 02, 2020 21:41
Reaction of an Al‐centered anion with toluene proceeded to form C−H cleaved product with a perfect meta‐selectivity and a relatively small kinetic isotope effect (KIE, k H/k D=1.51). DFT calculations suggested a two‐step reaction mechanism and electronically controlled meta‐selectivity arising from the electron‐donating methyl group. The reaction with other mono‐substituted arenes was also investigated. Abstract Reaction of an Al‐centered anion with toluene proceeded to form C−H cleaved...
Wed Sep 02, 2020 21:39
A tethering strategy based on SOMO‐HOMO‐converted dicarboxylate radical anions for site‐specific aminations of imidates and amidines is presented. A variety of β‐ and γ‐amino alcohols and dihydroimidazoles are efficiently prepared in good to excellent yields with high functional‐group tolerance under visible‐light irradiation, and late‐stage functionalization of bioactive molecules is also achieved with non‐covalent interaction patterns. Abstract The utilization of N‐centered radicals to...
Wed Sep 02, 2020 21:39
Exclusive meta selectivity was observed in C−H activation reactions of an electron‐rich AlI aluminyl compound with arenes (see scheme). The selectivity is based on similar electronic factors to those that determine the course of classical SNAr reactions, which implies the destabilisation of transition states featuring electron‐donating groups in ortho or para positions. Abstract The reactivity of the electron‐rich anionic AlI aluminyl compound K2[(NON)Al]2 (NON=4,5‐bis(2,6‐diisopropylanilido)‐2,7‐di‐tert‐butyl‐9,9‐dimethylxanthene)...
Wed Sep 02, 2020 21:38
We report the design and study of a catalytically controlled chemical reaction network (CRN). Specifically, we designed a fuel‐driven transient‐esterification CRN, where pyridine controls ester formation and imidazole controls ester hydrolysis. This fuel‐driven strategy was further implemented in a macromolecular system, where through variation of fuel and catalysts levels, we are able to control polymer conformation and aggregation. Abstract Signal transduction in living systems is the...
Wed Sep 02, 2020 21:38
A mass vaccination campaign against the SARS‐CoV‐2 virus is likely to be the most effective measure to fight the current COVID‐19 pandemic. Here the current COVID‐19 vaccine development efforts in (pre‐)clinical stage are reviewed. Abstract The current COVID‐19 pandemic has a tremendous impact on daily life world‐wide. Despite the ability to dampen the spread of SARS‐CoV‐2, the causative agent of the diseases, through restrictive interventions, it is believed that only effective vaccines...
Wed Sep 02, 2020 21:38
A general strategy was developed to functionalize nanoparticles with a cross‐linked (branched PEG–linear PAA–branched PEG, P3) surface coating. The P3 coating allowed rapid excretion of nanomaterials from the body, establishing a foundation for nanomedicine‐based theranostics for clinical translation for human use. Abstract Most NIR‐IIb fluorophores are nanoparticle‐based probes with long retention (≈1 month or longer) in the body. Here, we applied a novel cross‐linked coating to functionalize...
Wed Sep 02, 2020 21:36
Self‐Assembled Anion‐Binding Cryptand for the Selective Liquid–Liquid Extraction of Phosphate Anions
The ligands L1 and L2 form trinuclear self‐assemblies with Cu2+ (i.e. [L 2Cu3]6+) both of which act as hosts to a variety of anions. Inclusion of long aliphatic chains on these ligands allows the self‐assemblies to extract anions from aqueous media into organic solvents. Phosphate anions can be removed from water efficiently and highly selectively in the presence of other anions. Abstract The ligands L1 and L2 form trinuclear self‐assembled complexes with Cu2+ (i.e. [(L1 )2Cu3]6+...
Wed Sep 02, 2020 21:35
Using proteins to actuate DNA systems is challenging because it requires non‐trivial binding‐induced mechanisms. We demonstrate a strategy to perform DNA‐based molecular operations controlled by DNA‐binding proteins using synthetic DNA translators that convert specific protein‐binding events into trigger inputs through a programmable structural transition, allowing the establishment of artificial biomolecular communication pathways. Abstract Integrating dynamic DNA nanotechnology with protein‐controlled...
Wed Sep 02, 2020 21:35
We show for the first time that atomically dispersed Rh cations on ceria, prepared via high‐temperature atom trapping synthesis, are the active species for (CO+NO) reaction. This provides a direct link with the organometallic homogeneous Rh(I) complexes capable of catalyzing dry (CO+NO) reaction but without the stability concern. In particular, thermally stable Rh cations in 0.1wt% Rh1/CeO2 achieve full NO conversion with a TOF of ~ 330 hr‐1 per Rh atom at 120 ⁰C. Under dry conditions, the main...
Wed Sep 02, 2020 21:35
The addition of a stammer discontinuity within a de novo designed 3SCC containing a symmetric (His)3 metal binding site enhances copper nitrite reductase activity and ablates zinc esterase activity. These results suggest catalytic activity of designed α‐helical systems can be modulated by inclusion of discontinuity insertions and deletions. Abstract While many life‐critical reactions would be infeasibly slow without metal cofactors, a detailed understanding of how protein structure can...
Wed Sep 02, 2020 21:30
To identify exact protective epitopes of the immunologically active capsular polysaccharide (CPS) of autism‐related bacterium Clostridium bolteae, a series of the CPS glycans, up to an octadecasaccharide, was chemically synthesized for the first time. Glycan microarray analysis of rabbit sera against inactivated C. bolteae revealed that the tetrasaccharide fragment of CPS may be a key motif for designing glycoconjugate vaccines against C. bolteae. Abstract The gut pathogen Clostridium bolteae...
Wed Sep 02, 2020 21:29
Center of attention: This Review gives an overview of methods to investigate HER‐active atomic centers and discusses active sites with different coordination configurations. Active centers with one metal atom, two different metal atoms, as well as nonmetal atoms are analyzed at the atomic scale. Future research perspectives are also proposed. HER=hydrogen evolution reaction. Abstract The evolution of hydrogen from water using renewable electrical energy is a topic of current interest. Pt/C...
Wed Sep 02, 2020 21:29
Already there: Polymers obtained by RAFT polymerization with thiocarbonylthio transfer agents possessing an electron‐deficient carbon–sulfur double bond undergo bioconjugation by hetero‐Diels–Alder cycloaddition, without the need for other reactive end groups. This ligation occurs over a few hours, at ambient temperature and near‐neutral pH, without any catalyst required. Abstract We introduce the bioconjugation of polymers synthesized by RAFT polymerization, bearing no specific functional...
Wed Sep 02, 2020 21:28
Carbon molecular sieve (CMS) membranes show exceptional separation performance and scalable processing attributes attractive for important, similar‐sized gas pairs. A mathematical and physical framework to understand these attributes is presented. Abstract Demand for energy‐efficient gas separations exists across many industrial processes, and membranes can aid in meeting this demand. Carbon molecular sieve (CMS) membranes show exceptional separation performance and scalable processing...
Wed Sep 02, 2020 21:28
Metal‐containing zeolites outside the comfort zone: With a growing demand for the sustainable production of chemicals, new catalysts are vital. Here we highlight recent examples of metal‐containing zeolite catalysts operating under harsh conditions in reactions such as high‐temperature alkane conversion and biomass valorization in liquid water. Abstract The development of catalysts that can operate under exceptionally harsh and unconventional conditions is of critical importance for the...
Wed Sep 02, 2020 21:28
Conjugated oligoelectrolytes (COEs) readily intercalate into model and natural lipid bilayer membranes. By introducing an azobenzene moiety into their backbone these COEs can be isomerized within the bilayer. This structural change of the COE leads to permeabilization of the membrane. Abstract The synthesis of a new conjugated oligoelectrolyte (COE), namely DSAzB, is described, which contains a conjugated core bearing a diazene moiety in the center of its electronically delocalized structure....
Wed Sep 02, 2020 21:26
The use of fluorescent probes for studying biological systems has been crucial to our understanding of health and disease, with targeted, selective sensors providing us with highly specific biological information. This Minireview gives an overview of the different methods used to functionalise commonly used fluorophores with both sensing and targeting groups. Key directions for future research in this field are also presented. Abstract A key current challenge in biological research is the...
Wed Sep 02, 2020 21:26
Cu‐catalyzed asymmetric cyanation and etherification reactions of enamides were established, where a carbon‐centered radical adjacent to a nitrogen atom (CRAN) is enantioselectively trapped by a chiral CuII species. Asymmetric cyanation of vinyl esters was also demonstrated. The reactions feature mild conditions and high functional group tolerance, and give chiral α‐cyano amides, α‐cyano esters, and hemiaminals in good yields with excellent enantioselectivity. Abstract The first copper‐catalyzed...
Wed Sep 02, 2020 21:25
The synergy between different non‐covalent interactions is modulated to achieve supramolecular hybrids as electron donor‐acceptor photoactive systems consisting of a tetracationic zinc(II) phthalocyanine and anionic water‐soluble fullerenes. In the resulting monocrystalline assemblies, all the fundamental processes of natural photosynthesis are operative and give rise to highly efficient artificial photosynthetic systems. Abstract In the scientific race to build up photoactive electron...
Wed Sep 02, 2020 21:24
A masking group that is selectively and efficiently removed by external radiation was developed based on a unique aromatic hydroxylation and .OH from the radiolysis of H2O. This radiation‐induced cleavage was demonstrated in living systems by switching on an .OH‐responsive fluorescent probe in cells and tumor xenografts. Abstract Radiation‐induced cleavage for controlled release in vivo is yet to be established. We demonstrate the use of 3,5‐dihydroxybenzyl carbamate (DHBC) as a masking...
Wed Sep 02, 2020 21:24
Polar functionalized isotactic and syndiotactic polypropylenes (PPs) are synthesized by direct, masking‐reagent‐free propylene and amino–olefin (AO, CH2=CH(CH2) x NnPr2, x=2, 3, 6) copolymerizations using the activated precatalysts rac‐[Me2Si(indenyl)2]ZrMe2 and [Me2C(Cp)(fluorenyl)]ZrMe2, respectively. Polymerization activities at 25 °C are as high as 4208 and 535 kg/(mol h atm) with AO incorporation up to 4.0 mol % and 1.6 mol %, respectively Abstract Polar functionalized isotactic...
Wed Sep 02, 2020 21:24
Transforming Computed Energy Landscapes into Experimental Realities: The Role of Structural Rugosity
The link between structural surface rugosity and ease of crystallisation has been explored (see picture). Smooth polymorphs were found to crystallise more readily than rough polymorphs. A code was written to compute crystal rugosity and applied to crystal structure prediction calculations, thus affording a new way of linking landscapes to experimentation. Abstract We exploit the possible link between structural surface roughness and difficulty of crystallisation. Polymorphs with smooth...
Wed Sep 02, 2020 21:23
Nibalamin (Nibl), the novel NiII analogue of vitamin B12, was synthesized from the metal‐free B12 ligand hydrogenobalamin, prepared from biosynthetic hydrogenobyric acid (Hby). An X‐ray crystal analysis of nibyric acid, the NiII complex of Hby, revealed the first structural details of a nickel complex of a natural corrin ligand. Nibl is a structural mimic of the corresponding four‐coordinate cobalamins, which are of interest in biological investigations. Abstract The (formal) replacement...
Wed Sep 02, 2020 20:28
Hierarchical carbohydrate architectures serve multiple roles in Nature. Hardly any correlations between the carbohydrate chemical structures and the material properties are available due to the lack of standards and suitable analytic techniques. Therefore, designer carbohydrate materials remain highly unexplored, as compared to peptides and nucleic acids. Here, a synthetic D‐glucose disaccharide, DD , is chosen as model to explore carbohydrate materials. Microcrystal electron diffraction (MicroED),...
Wed Sep 02, 2020 20:00
Renal tubular secretion is an active efflux pathway for the kidneys to remove molecules but has never been used to enhance kidney cancer targeting. Herein, we report the first renal tubule‐secretable near infrared‐emitting fluorophore, indocyanine green (ICG) conjugated with a 2100 Da PEG molecule (ICG‐PEG45) and its advantages in hyperfluorescence imaging of kidney cancers, which cannot be achieved with hepatobiliary‐ and glomerular‐clearable ICG. This pathway‐dependent targeting of kidney cancer...
Wed Sep 02, 2020 18:29
In comparison with the fast development of binary mixture separations, ternary mixture separations are significantly more difficult and have rarely been realized by a single material. Herein, a new strategy of tuning the gate‐opening pressure of flexible MOFs is developed to tackle such a challenge. As demonstrated by a flexible framework NTU‐65, the gate‐opening pressure of ethylene (C2H4), acetylene (C2H2), and carbon dioxide (CO2) can be regulated by temperatures. Therefore, efficient sieving...
Wed Sep 02, 2020 17:59
Recently, various titanium dioxide (TiO2) nanostructures have received increasing attention in the fields of energy conversion and storage due to extraordinary electrochemical properties. However, these particulate nanomaterials exclusively exist in the powder form, which may cause health risks and environmental hazards. Here we report a novel, highly elastic bulk form of TiO2 for safe use and easy recycling. Specifically, TiO2 nanofibrous aerogels (NAs) consisting of resiliently bonded, flexible...
Wed Sep 02, 2020 17:58
Zero‐dimensional (0D) organic metal halide hybrids have emerged as a new class of luminescent materials with exceptional structural and photophysical tunability, thanks to the rich choices of organic cations and metal halides for the formation of ionically bonded systems. Here we report photophysical tuning of a series of tetraphenylphosphonium (TPP) metal halide hybrids containing distinct metal halides, TPP 2 MX n (MX n = SbCl 5 , MnCl 4 , ZnCl 4 , ZnCl 2 Br 2 , ZnBr 4 ), from...
Wed Sep 02, 2020 16:58
Aluminum‐containing adjuvants used in vaccine formulations suffer from low cellular immunity, severe aggregation and cerebral accumulation problems. Conventional aluminosilicates widely used in chemical industry focus mainly on acidic sites for catalytic applications, but are rarely used as adjuvants. We report an innovative “ligand‐assisted steric hindrance” strategy to create a high density of six‐coordinate VI Al‐OH groups with basicity on dendritic mesoporous silica nanoparticles as new nanoadjuvants...
Wed Sep 02, 2020 16:31
Developing the competency of molecular sorbents for energy‐saving applications, such as C8 separations, requires efficient, stable, scalable and easily recyclable materials that can readily transition to commercial implementation. Here, we report an azobenzene‐based cage for the selective separation of p ‐xylene isomer across a range of C8 isomers in both vapor and liquid states with selectivity that is higher than the reported all‐organic sorbents. Interestingly, the crystal structure shows non‐porous...
Wed Sep 02, 2020 16:30
Main group Indium (In) is a promising electrocatalyst which triggers CO2 reduction to formate, while the high overpotential and low Faradaic efficiency (FE) hinder its practical application. Herein, we rationally design a new In single atom catalyst containing exclusive isolated Inδ+‐N4 atomic interface sites for CO2 electroreduction to formate with high efficiency. This catalyst exhibites an extremely large turnover frequency (TOF) up to 12500 h−1 at ‐0.95 V vs. RHE, with FE for formate of 96 %...
Wed Sep 02, 2020 16:29
Lead halide perovskites are considered to be most promising photovoltaic materials. Highest efficiency and improved stability of perovskite solar cells have been achieved by using cation and anion mixtures. Experimental information on electronic and ionic charge carriers is key to evaluate device performance, as well as processes of photo‐decomposition and photo‐demixing which are observed in these materials. Here, we measure ionic and electronic transport properties and investigate various cation...
Wed Sep 02, 2020 16:29
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