The ability to monitor drug and biomarker concentrations in the body with high frequency and in real time would revolutionize our understanding of biology and our capacity to personalize medicine. The few in‐vivo molecular sensors that currently exist, however, all rely on the specific chemical or enzymatic reactivity of their targets and thus are not generalizable. In response, we demonstrate here an electrochemical sensing architecture based on binding‐induced protein folding that is (1) independent...
Wed Jul 15, 2020 22:59
The meta junction is proposed to realize efficient thermally activated delayed fluorescence (TADF) in donor‐acceptor (D‐A) conjugated polymers. Based on triphenylamine as D and dicyanobenzene as A, as a proof of concept, a series of D‐A conjugated polymers has been developed by changing their connection sites. When the junction between D and A is tuned from para to meta, the singlet‐triplet energy splitting (∆ E ST ) is found to be significantly decreased from 0.44 to 0.10 eV because of the increasing...
Wed Jul 15, 2020 11:00
Hydrosilylation reactions, which allow the addition of Si‐H to C=C/C≡C bonds, are typically catalyzed by homogeneous noble metal catalysts (Pt, Rh, Ir and Ru). Although excellent activity and selectivity can be obtained, the price, separation and metal residues of these precious catalysts are problems in the silicone industry. Thus, a strong interest in more sustainable catalysts and for more economic processes exists. In this respect, recently disclosed hydrosilylations using catalysts based on...
Wed Jul 15, 2020 21:25
The rampant generation of lithium hydroxide and carbonate impurities, commonly known as ‘residual lithium’, is a practical obstacle to the mass‐scale synthesis and handling of high‐nickel (>90%) layered oxides and their use as high‐energy‐density cathodes for lithium‐ion batteries. Herein, we suggest a simple in situ method to control the residual lithium chemistry of a high‐nickel lithium layered oxide, Li(Ni 0.91 Co 0.06 Mn 0.03 )O 2 (NCM9163), with minimal side effects. Based on thermodynamic...
Wed Jul 15, 2020 19:00
Micro/nanoscale photonic barcodes based on multicolor luminescent segmented heterojunctions hold exotic potential applications in information security. However, such multicolor heterojunctions reported thus far are exclusively based on static luminescent signals, thus restraining their application in advanced confidential information protection. Here, we report on a strategy to design responsive photonic barcodes with heterobimetallic (Tb 3+ /Eu 3+ ) MOFs multicolor heterostructures. The spatial...
Wed Jul 15, 2020 17:23
Pdots and moonbeams : By controlling the population of photogenerated holes, dual‐mode superresolution imaging with semiconducting polymer dots was demonstrated. The localization precision achieved is 3–8 times better than the typical resolution obtained by localization of dyes and fluorescent proteins, which allows the hollow structure of microtubules to be resolved. Abstract In a conjugated polymer‐based single‐particle heterojunction, stochastic fluctuations of the photogenerated hole...
Wed Jul 15, 2020 17:08
The first example of a controlled radical polymerization of ethylene using iodine transfer polymerization (ITP) is performed under mild conditions (≤ 100 °C and ≤ 200 bar). Different commercially available, cheap, and non‐toxic iodo alkyls (R‐I) were used as chain‐transfer agents (CTAs) in combination with 2,2’‐azobis(2‐methylpropionitrile) (AIBN) to investigate the impact of the R‐group on the polymerization behaviour. These systems showed no rate retardation and no significant loss of chain ends....
Wed Jul 15, 2020 15:24
KAT o'nine tails : Post‐polymerization modification and ligation of polymers under aqueous conditions is achieved by incorporating potassium acyltrifluoroborates (KATs) at side chains or the polymer terminus. This enables the attachment of unprotected small molecules, chromophores, and peptide‐based drugs through rapid amide‐forming ligations of KATs in water. Direct ligation to other polymers enables the synthesis of linear and branched block copolymers. Abstract We report the synthesis...
Wed Jul 15, 2020 15:24
Step by step : A well‐defined graphene‐like 2D polymer with a wide band gap has been fabricated on Au(111). Distinct stepwise on‐surface reactions, including alkynyl cyclotrimerization, C−O bond cleavage, and C−H bond activation, were triggered on demand, leading to product evolution in a controlled step‐by‐step manner. Abstract Developing graphene‐like two‐dimensional materials naturally possessing a band gap has sparked enormous interest. Thanks to the inherent wide band gap and high...
Wed Jul 15, 2020 15:22
Molecular diffusion ultimately determines the sensitivity of gas sensors, whose driving force is directly proportional to the analyte concentration gradient. When the vertical diffusion was switched to the integration of vertical and horizontal diffusion, the gas sensors fabricated on patterned arrays displayed an order of magnitude higher sensitivity than their counterpart film‐based sensors. Abstract The diffusion of target analytes is a determining factor for the sensitivity of a given...
Wed Jul 15, 2020 15:21
Trisubstituted alkenes undergo Fe‐catalyzed asymmetric cis‐dihydroxylation (AD) with H2O2 to give cis‐diols in up to 98 % yield and with up to >99.9 % ee . This Fe catalyst/H2O2 AD method is applicable to a variety of trisubstituted alkenes bearing electron‐withdrawing substituents, such as ester and amide groups. Mechanistic studies by 18O‐labeling, UV/Vis spectroscopy, ESI‐MS, NMR spectroscopy, EPR spectrocopy, and DFT calculations were performed. Abstract Reliable methods for enantioselective...
Wed Jul 15, 2020 15:20
The synthesis of tetraalkylammonium tetrafluoridochlorate(III) is described. An acetonitrile solution of the alkylammonium chloride salt is reacted with diluted fluorine at low temperature. The application as fluorinating agent is evaluated by the reaction with Ph2S2 to PhSF5, the transformation of the CN moieties in acetonitrile and [B(CN)4]− into CF3, reaction with CO to COF2 and the formation of tetrafluoridoaurate [AuF4]− with elemental gold. Abstract A facile one‐pot gram‐scale synthesis...
Wed Jul 15, 2020 15:20
May I interrupt? Taking advantage of the interrupted Pummerer reaction, trifluoromethyl sulfoxides engage in the metal‐free C−H trifluoromethylthiolation of (hetero)arenes, including drug molecules and natural products. This new class of trifluoromethylthiolating reagent exploits a new strategy for trifluoromethylthiolation in which sulfonium salts are assembled and selectively deconstructed. Abstract Trifluoromethyl sulfoxides are a new class of trifluoromethylthiolating reagent. The...
Wed Jul 15, 2020 15:20
2 Become 1 : Lewis acidic boranes are employed in the metal‐free alkenylation reactions of aryl esters with α‐diazoesters to give highly functionalized alkene, enyne, and diene products in good to excellent yields. DFT studies have elucidated the mechanism for the reaction. Abstract Herein we report a facile, mild reaction protocol to form carbon–carbon bonds in the absence of transition metal catalysts. We demonstrate the metal‐free alkenylation reactions of aryl esters with α‐diazoesters...
Wed Jul 15, 2020 15:17
CH–π interactions are crucial determinants for the affinity of arguably every drug molecule. PI by NMR can differentiate the strength of protein–ligand CH–π interactions in solution. By combining selective amino‐acid side‐chain labeling with 1H‐13C NMR, CH–π interactions can be identified based solely on 1H chemical shift values. This information serves as a proxy for the strength of each individual CH–π interaction. Abstract While CH–π interactions with target proteins are crucial determinants...
Wed Jul 15, 2020 15:17
Inspired by the natural [NiFe]‐H 2 ase , we designed mimic 1 , (dppe)Ni(m‐pdt)(m‐Cl)Ru(CO) 2 Cl, in order to realize effective H 2 evolution under photocatalytic conditions. However, a new species 2 was captured in the course of photo‐, electro‐, and chemo‐ one‐electron reduction. Experimental studies of in‐situ infrared spectroscopy (IR), electron paramagnetic resonance (EPR), nuclear magnetic resonance (NMR), X‐ray absorption spectroscopy (XAS), as well as density functional theory...
Wed Jul 15, 2020 15:07
The development of enzymes capable of mediating abiological reactions offers new opportunities for sustainable chemistry. Here we report the development of biological catalysts derived from sperm whale myoglobin that exploit a carbene transfer mechanism for the asymmetric synthesis of cyclopropane‐fused‐δ‐lactones, which are key structural motifs found in many biologically active natural products. While hemin, wild‐type myoglobin, and other hemoproteins are unable to catalyze this reaction, the myoglobin...
Wed Jul 15, 2020 15:06
By integration of iminyl radical‐triggered 1,5‐hydrogen atom transfer and (5+2) or (5+1) annulation processes, a series of structurally novel and interesting azepine and spiro‐tetrahydropyridine derivatives have been successfully prepared in moderate to good yields. This method utilizes FeCl 2 as the catalyst and readily available oximes as five‐atom units, and showcases broad substrate scope and good functional group compatibility. The annulation products can be easily converted into many valuable...
Wed Jul 15, 2020 15:06
Bringing DNA into the fold : A foldable polymer DNA origami assembled using T‐junction motifs is presented. It is shown that a set of just two interaction rules can be used to assemble simple T‐junction origami motifs and that assembly can be performed at room temperature. Abstract DNA self‐assembly allows the construction of nanometre‐scale structures and devices. Structures with thousands of unique components are routinely assembled in good yield. Experimental progress has been rapid,...
Wed Jul 15, 2020 14:52
New optics : The first fluorosulfonic ultraviolet (UV) nonlinear optical (NLO) material, C(NH2)3SO3F, is rationally designed by taking KBe2BO3F2 (KBBF) as the parent compound. C(NH2)3SO3F is a metal‐free UV NLO crystal that benefits from the coplanar configuration of the C(NH2)3 + cationic groups, and it possesses a large second harmonic generation response of 5×KDP and a moderate birefringence of 0.133@1064 nm. Abstract The first fluorosulfonic ultraviolet (UV) nonlinear optical (NLO)...
Wed Jul 15, 2020 14:49
A mixed ion–electron conducting amorphous phase of tetrathiamolybdate (MoS4 2−) with mixed Mo and S valences, shows a sustainable reversible capacity of 500 mAh g−1 (black plot) derived from cumulative anionic sulfide (red plot) and cationic molybdenum (blue plot) redox properties. The material is equally suitable for lithium‐ and sodium‐cation storage, with further avenues to be explored toward multivalent and higher voltage redox materials. Abstract We report the electrochemistry of...
Wed Jul 15, 2020 14:49
Curveball : A non‐lithography hydrodynamic printing strategy is proposed for preparing micro/nanostructures on three‐dimensional curved surfaces. A capillary pumped function between the template and curved substrates assembles nanoparticles on curved surfaces at the resolution of single nanoparticles. The strategy provides a general platform for optoelectronics beyond flat surfaces. Abstract A key issue of micro/nano devices is how to integrate micro/nanostructures with specified chemical...
Wed Jul 15, 2020 14:49
Regioselective functionalization of acenes : A novel synthetic strategy is introduced that enables a regioselective functionalization of acenes, which is demonstrated using the example of unilaterally substituted fluoroacenes. The packing motif and optoelectronic solid‐state properties of these new materials are compared to the properties of their parental acenes. Abstract The rapid development of organic electronics is closely related to the availability of molecular materials with specific...
Wed Jul 15, 2020 14:48
Caught in a web : Inspired by the similarity of the 3D structure of superb‐uranyl binding protein SUP to that of spidroin from spider silk, a chimeric protein, DSUP, containing two copies of SUP was designed and spun into protein fiber. Impressively, the high‐strength DSUP fiber shows ultrahigh, ultrafast, and highly selective uranium extraction ability in natural seawater. Abstract The unique three‐dimensional structure of spidrion determines the outstanding mechanical properties of the...
Wed Jul 15, 2020 14:47
Calcium fluoride windows were functionalized to facilitate the growth of surface‐mounted metal–organic frameworks (SURMOF). The resulting HKUST‐1 SURMOF was measured by in situ IR spectroscopy during CO and NO adsorption. This work showcases the practicality for utilizing such calcium fluoride windows for in‐depth in situ studies of various functional porous materials. Abstract Surface‐mounted metal–organic frameworks (SURMOFs) show promising behavior for a manifold of applications. As...
Wed Jul 15, 2020 14:46
It takes two : By taking advantage of the synergistic interaction of a palladium catalyst and silver additive, a strategically novel synthetic method that enables the expedient site‐selective elaboration of pyridine derivatives was developed. The successful use of pyridylphosphonium salts as donors of a pyridyl anion equivalent greatly expands the range of competent nucleophilic coupling partners for palladium‐catalyzed cross‐coupling. Abstract Herein, we report a highly efficient and practical...
Wed Jul 15, 2020 14:45
A new member of the peryleneimide family, “flapping peryleneimide”, shows an unprecedented fluorogenic mechanism. A bent‐to‐planar conformational change in S1 induces quenching of the inherent peryleneimide fluorescence (FL), while a slight environmental change resulted in a remarkable increase in the FL quantum yield and the FL lifetime. Abstract Flapping fluorophores (FLAP) with a flexible 8π ring are rapidly gaining attention as a versatile photofunctional system. Here we report a highly...
Wed Jul 15, 2020 14:44
Short lp⋅⋅⋅π contacts in Z‐DNA steps result from a combination of compression effects induced by a highly strained structural context and an effective van der Waals (vdW) radius of a guanine sp2 carbon atom that is estimated to be much smaller than the standard 1.70 Å vdW radius of sp3 carbons generally used to assess the sub‐vdW character of these interactions. Abstract Current interest in lone‐pair⋅⋅⋅π (lp⋅⋅⋅π) interactions is gaining momentum in biochemistry and (supramolecular) chemistry....
Wed Jul 15, 2020 14:44
TEAD–YAP Interaction Inhibitors and MDM2 Binders from DNA‐Encoded Indole‐Focused Ugi Peptidomimetics
A focused approach : A DNA‐encoded peptoid library was designed by the Ugi multicomponent reaction around indole structures that mimic the side chain of tryptophan. Applying this focused library to the challenging cancer targets MDM2 and hTEAD4 yielded compounds for inhibitor development. Compounds binding to hTEAD4 disrupted the hTEAD4–YAP interaction, and reduced expression of a gene under control of the TEAD–YAP transcription factor complex. Abstract DNA‐encoded combinatorial synthesis...
Wed Jul 15, 2020 14:43
Gaining ground : Optical excitation of spiropyrans quantitatively transforms them into merocyanines with a strong intramolecular charge‐transfer (ICT) emission. The gain region of the merocyanine isomers shifted with photoisomerization because the increased polarity of the molecular environment lowered the ICT energy levels. Broadband‐tunable single‐mode lasing was achieved based on the controllable ICT processes in polymeric coupled microdisks. Abstract Miniaturized lasers with high spectral...
Wed Jul 15, 2020 14:43
The challenging nickel‐catalyzed mono α‐arylation of acetone with aryl chlorides, pivalates and carbamates has been achieved for the first time. A nickel/Josiphos‐based catalytic system is shown to feature unique catalytic behavior allowing highly selective formation of the desired mono α‐arylated acetone. The developed methodology was applied to a variety of (hetero)aryl chlorides including biologically relevant derivatives. The methodology has been extended to the unprecedented coupling of acetone...
Wed Jul 15, 2020 13:30
Single crystals of optoelectronic materials that respond to external stimuli, such as mechanical, light or heat are immensely attractive for next generation smart materials. Here we report single crystals of a green fluorescent protein (GFP) chromophore analogue with irreversible mechanical bending and associated unusual enhancement of the fluorescence, which is attributed to the strained molecular stacks in the perturbed structure. Soft crystalline materials with such fluorescence intensity modulations...
Wed Jul 15, 2020 12:28
Free radicals with reactive chemical properties can battle against tumors without causing drug resistance. Reactive oxygen species (ROS) has been widely used for cancer treatment, but regrettably, the common existence of O2 and H2O2 deficiency in tumor set a severe barrier for sufficient ROS production, leading to unsatisfactory anticancer outcomes. Here, we construct chlorine radical (•Cl) nano‐generator with inner upconversion nanoparticle (UCNP) coated by SiO2, and decorated with Ag0/AgCl hetero‐dots...
Wed Jul 15, 2020 12:28
Two‐dimensional covalent organic frameworks (2D COFs), which is an emerging class of crystalline porous polymers, have been recognized as a new platform for efficient solar‐to‐hydrogen energy conversion owing to their pre‐designable structures and tailor‐made functions. Herein, we demonstrate that slight modulation of the chemical structure of a typical photoactive 2D COF (Py‐HTP‐BT‐COF) via chlorination (Py‐ClTP‐BT‐COF) and fluorination (Py‐FTP‐BT‐COF) can lead to dramatically enhanced photocatalytic...
Wed Jul 15, 2020 11:45
We report a series of meltable Fe II complexes, which, depending on the length of aliphatic chains, display abrupt “forward” low‐spin to high‐spin transition or unprecedented melting‐triggered “reverse” high‐spin to low‐spin transition on temperature rise. The “reverse spin transition” is perfectly reproducible on thermal cycling and the obtained materials are easily processable in the form of thin film due to soft matter nature. We found that the discovered approach represents a potentially generalizable...
Wed Jul 15, 2020 11:45
Chronic obstructive pulmonary disease (COPD) is an intractable disease involving a sticky mucus layer and nano‐agents with the mucus‐penetrating capability offer a new way to deliver drugs therapeutically. However, drug release from nano‐vehicles requires optimization in order to enhance the therapeutic effects of COPD therapy. Herein, black phosphorus quantum dots (BPQDs) are combined with PEGylated chitosan nanospheres containing amikacin (designated as PEG@CS/BPQDs‐AM NPs). As a drug delivery...
Wed Jul 15, 2020 11:45
A spodium bond (SpB) is defined as the net attractive interaction between a Group 12 element acting as a Lewis acid and electron‐rich atoms (Lewis bases or anions). These noncovalent interactions involve antibonding Sp–ligand orbitals and are markedly different from coordination bonds. Evidence for SpBs is provided by ab initio calculations and examining solid‐state structures. Abstract The term spodium (Sp) bond is proposed to refer to a net attractive interaction between any element...
Wed Jul 15, 2020 11:35
Zeolite synthesis in an acidic medium is investigated. The isoelectric point (IEP) of the silica source is found to be the critical factor controlling the zeolite formation under acidic conditions. The zeolite crystalizes solely at a pH above the IEP when the silica particles are negatively charged. Abstract Aluminosilicate zeolites are synthesized under hydrothermal conditions in a basic/alkaline medium in the pH range between 9 and 14. The synthesis of MFI‐type zeolite in an acidic medium...
Wed Jul 15, 2020 11:34
The anisotropic Poisson effect of an elastic 9,10‐dibromoanthracene single crystal was observed. The macroscopic anisotropic Poisson effect is well consistent with microscopic anisotropic Poisson effect in the level of molecular packing structure that was simulated by DFT calculations. Its bending and stretching deformation‐induced fluorescence changes was observed as well. Abstract Elastic organic crystals have attracted considerable attention as next‐generation flexible smart materials....
Tue Jul 14, 2020 21:59
A new application of high‐performance liquid/liquid counter current chromatography system demonstrated high reaction rates and excellent yields for biphasic reactions, exemplified with steroselective phase‐transfer catalysed reactions and biocatalytic synthesis of sesquiterpenes. Catalysis in the HPCCC system was up to 70 times faster than in batch reactors and up to 10 times faster than in segmented flow systems with nearly quantitative yields. Abstract Process intensification through...
Tue Jul 14, 2020 21:59
Without transition metal catalysts , diazo quinones undergo cross‐coupling with catechol boronic esters to give a variety of biaryls and alkenyl phenols in up to 96 % yield under mild conditions. The reaction is applicable to the synthesis of multi‐substituted triphenylenes and natural products honokiol, moracin M, and stemofuran A. DFT calculations revealed a stepwise mechanism involving attack of the boronic ester by a singlet quinone carbene. Abstract A transition‐metal‐free C(sp2)−C(sp2)...
Tue Jul 14, 2020 21:57
An efficient Cu‐catalyzed approach is reported that enables the conversion of alkyl pyridinium salts, which can be readily synthesized from the corresponding alkyl amines, to their alkyl difluoromethane analogues. This method can be applied to the late‐stage modification of complex amino‐containing pharmaceuticals. Abstract The difluoromethyl group (CF2H) is considered to be a lipophilic and metabolically stable bioisostere of an amino (NH2) group. Therefore, methods that can rapidly convert...
Tue Jul 14, 2020 21:57
The distinctive self‐assembling features of N‐annulated perylene bisimides 1 and 2 are reported. Diester 1 , with no H‐bonding interaction operating, affords stable cooperative J‐type supramolecular polymers. The incorporation of amide functional groups in 2 results in a stimulating differentiation with several pathways to achieve up to three J‐type aggregates and a fourth H‐type aggregate depending on the experimental conditions utilized. Key: methylcyclohexane (MCH), toluene (Tol). ...
Tue Jul 14, 2020 21:57
The biomimetic synthesis of aromatic polyketides from macrocyclic substrates by means of catalyst‐controlled transannular cyclization cascades is described. The macrocyclic substrates which feature increased stability and fewer conformational states were thereby transformed into several distinct polyketide scaffolds. The catalyst‐controlled transannular cyclizations selectively led to aromatic polyketides with a defined folding and oxygenation pattern, thus emulating ß‐keto‐processing steps of polyketide...
Tue Jul 14, 2020 21:27
Tuning CO 2 hydrogenation selectivity to obtain targeted value‐added chemicals and fuels has attracted great yet ever‐increasing attention. However, a fundamental understanding of the nature to control the selectivity is still lacking, posing a challenge in catalyst design and development. Here, we report our new discovery in ambient pressure CO 2 hydrogenation reaction where selectivity can be completely reversed by simply changing the crystal phases of TiO 2 support (anatase ‐ or rutile‐TiO...
Tue Jul 14, 2020 20:41
Metallic catalysts with nanopores are advantageous on improving both activity and selectivity, while the reason behind that remains unclear all along. In this work, porous Zn nanoparticles (P‐Zn) were adopted as a model catalyst to investigate the catalytic behavior of metallic nanopores. In‐situ X‐ray absorption spectroscopy, in‐situ Fourier transform infrared spectroscopy and density functional theory (DFT) analyses reveal that the concave surface of nanopores works like a pincer to capture and...
Tue Jul 14, 2020 20:41
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