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In solid‐state lithium metal batteries (SSLMBs), the inhomogeneous electrolyte‐electrode interphase layer aggravates the interfacial stability, leading to discontinuous interfacial ion/charge transport and continuous degradation of the electrolyte. Herein, we constructed an anion‐modulated ionic conductor (AMIC) that enables in situ construction of electrolyte/electrode interphases for high‐voltage SSLMBs by exploiting conformational transitions under multiple interactions between polymer and lithium salt anions. Anions modulate the decomposition behavior of supramolecular poly (vinylene carbonate) (PVC) at the electrode interface by changing the spatial conformation of the polymer chains, which further enhances ion transport and stabilizes the interfacial morphology. In addition, the AMIC weakens the "Li+‐solvation" and increases Li+ vehicle sites, thereby enhancing the lithium‐ion transport number (tLi+=~0.67). Consequently, Li || LiNi0.8Co0.1Mn0.1O2 cell maintains about 85 % capacity retention and Coulombic efficiency >99.8 % in 200 cycles at a charge cut‐off voltage of 4.5 V. This study provides a new understanding of lithium salt anions regulating polymer chain segment behavior in the solid‐state polymer electrolyte (SPE) and highlights the importance of the ion environment in the construction of interfacial phases and ionic conduction. [ABSTRACT FROM AUTHOR]

With the oxygen conversion efficiency of metal‐free carbon‐based fuel cells dramatically improved, the building blocks of covalent organic frameworks (COFs) raised principal concerns on the catalytic active sites with indistinct electronic states. Herein, to address this issue, we demonstrate COFs for oxygen reduction reaction (ORR) by regulating the edge‐hanging thiophene units, and the molecular geometries are further modulated via positional thiophene isomerization strategy, affording isomeric COF‐α with 2‐substitution and COF‐β with 3‐substitution on the frameworks. The electronic states and intermediate adsorption ability are well‐regulated through geometric modification, resulting in controllable chemical activity and local density of π‐electrons. Notably, the introduction of thiophene units with different substitution positions into a pristine pure carbon‐based COF model COF‐Ph achieves excellent activity with a half‐wave potential of 0.76 V versus the reversible hydrogen electrode, which is higher than most of those metal‐free or metal‐based electrocatalysts. Utilizing the combination of theoretical prediction and in situ Raman spectra, we show that the isomeric thiophene skeleton (COF‐α and COF‐β) can induce the dangling unit activation, accurately identifying the pentacyclic‐carbon (thiophene α‐position) adjacent to sulfur atom as active sites. The results suggest that the isomeric dangling groups in COFs are suitable for the ORR with promising geometry construction. [ABSTRACT FROM AUTHOR]

Water is a ubiquitous component in heterogeneous catalysis over zeolites and can significantly influence the catalyst performance. However, the detailed mechanism insights into zeolite‐catalyzed reactions under microscale aqueous environment remain elusive. Here, using multiple dimensional solid‐state NMR experiments coupled with ultrahigh magic angle spinning technique and theoretical simulations, we establish a fundamental understanding of the role of water in benzene methylation over ZSM‐5 zeolite under water vapor conditions. We show that water competes with benzene for the active sites of zeolite and facilitates the bimolecular reaction mechanism. The growth of water clusters induces a micro‐hydrophobic effect in zeolite pores, which reorients benzene molecules and drives their interactions with surface methoxy species (SMS) on zeolite. We identify the formation and evolution of active SMS‐Benzene complexes in a microscale aqueous environment and demonstrate that their accumulation in zeolite pores boosts benzene conversion and methylation. [ABSTRACT FROM AUTHOR]

Heterogeneous catalytic ammoxidation provides an eco‐friendly route for the cyanide‐free synthesis of nitrile compounds, which are important precursors for synthetic chemistry and pharmaceutical applications. However, in general such a process requires high pressures of molecular oxygen at elevated temperatures to accelerate the oxygen reduction and imine dehydrogenation steps, which is highly risky in practical applications. Here, we report an electric field enhanced ammoxidation system using a supported Fe clusters catalyst (Fe/NC), which enables efficient synthesis of nitriles from the corresponding aldehydes under ambient air pressure at room temperature (RT). A synergistic effect between the external electric field and the Fe/NC catalyst promotes the ammonia activation and the dehydrogenation of the generated imine intermediates and avoids the unwanted backwards reaction to aldehydes. This electric field enhanced ammoxidation system presents high efficiency and selectivity for the conversion of a series of aldehydes under mild conditions with high durability, rendering it an attractive process for the green synthesis of nitriles with fragile functional groups. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrate reduction sustainably produces ammonia and alleviates water pollution, yet is still challenging due to the kinetic mismatch and hydrogen evolution competition. Cu/Cu2O heterojunction is proven effective to break the rate‐determining NO3−‐to‐NO2− step for efficient NH3 conversion, while it is unstable due to electrochemical reconstruction. Here we report a programmable pulsed electrolysis strategy to achieve reliable Cu/Cu2O structure, where Cu is oxidized to CuO during oxidation pulse, then regenerating Cu/Cu2O upon reduction. Alloying with Ni further modulates hydrogen adsorption, which transfers from Ni/Ni(OH)2 to N‐containing intermediates on Cu/Cu2O, promoting NH3 formation with a high NO3−‐to‐NH3 Faraday efficiency (88.0±1.6 %, pH 12) and NH3 yield rate (583.6±2.4 μmol cm−2 h−1) under optimal pulsed conditions. This work provides new insights to in situ electrochemically regulate catalysts for NO3−‐to‐NH3 conversion. [ABSTRACT FROM AUTHOR]

Understanding the acid sites on zeolites is vital for the establishment of catalyst structure–activity relationship and exploration of their potential applications in heterogeneous catalysis. Here, we report the identification of active framework Lewis acid sites on ZSM‐5 zeolites. The structures of framework‐associated tri‐coordinated Al that is bonding with hydroxyl groups are determined by using one‐ dimensional (1D) 31P and two‐dimensional (2D) 31P‐{27Al} NMR spectroscopy of trimethylphosphine oxide probe molecule. 2D 13C‐{27Al} NMR correlation experiments allow the observation of favorable formation of methoxy species on the framework‐associated Al Lewis acid sites in methanol reaction at low temperature, which is corroborated by density functional theory calculations. These methoxy species contribute to the further conversion of methanol to hydrocarbons as active C1 species. The results provide new insights into the Lewis acidity of zeolites. [ABSTRACT FROM AUTHOR]

Achieving wide‐range tunable emission colors, especially in the solid state of single‐fluorophore materials, remains a significant challenge. Herein, we report a molecular design strategy that affords wide‐range excitation‐dependent emissions spanning over ≈230 nm in crystalline states. Under the donor‐π‐acceptor configuration, we judiciously choose a rotatable acceptor fragment, o‐carborane, to enrich conformational diversities in the crystalline state and generate conformation‐dependent multicolor emissions. We further show that this molecular platform is generalizable in creating crystalline materials with multicolor emissions. Based on these materials, a high‐capacity information storage device and a finite‐state machine were fabricated to showcase multicolor displays and information storage. [ABSTRACT FROM AUTHOR]

Programming the organization of semiconducting polymers to form well‐defined nanoarchitectures is desirable for fabricating functional materials. In this work, semiconducting copolymers, poly(cholesterol allene)‐b‐poly(3‐hexylthiophene) (PCA‐b‐P3HT) containing helical PCA and poly(alkoxy allene)‐b‐poly(3‐hexylthiophene) (PAA‐b‐P3HT) containing achiral PAA segments, were prepared. Crystallization of P3HT and helicity of PCA drove PCA‐b‐P3HT self‐assemble into spherical nanoparticles that gradually transformed into one‐handed helical nanofibers. The chirality of PCA was transferred to the supramolecular architectures, induced high optical activity in P3HT. Interestingly, the chiral seed micelles of PCA‐b‐P3HT induced asymmetric copolymerization of achiral PAA‐b‐P3HT, which led to helical supramolecular block copolymers with defined helicity and controlled length. Remarkably, the supramolecular copolymers showed white‐light emission and circularly polarized luminescence. [ABSTRACT FROM AUTHOR]

The glycosylative modification of peptides could improve the pharmacological properties of peptide drugs and deliver them efficiently to the target sites. Compared with O‐/N‐glycosides, C‐glycosides exhibit more metabolic stability. We here disclose the first example of visible‐light‐promoted and Cu‐catalyzed stereoselective C‐glycosylation. The mild reaction conditions are compatible with various carbohydrate substrates, as demonstrated with a series of monosaccharides and a disaccharide, and are amenable to the synthesis of a wide variety of C‐glycoamino acids and C‐glycopeptidomimetics with good yields and excellent stereoselectivities. The dual‐functional photocatalyst formed in situ via coordination of the glycine derivative and the chiral phosphine Cu complex could not only catalyze the photoredox process but also control the stereoselectivity of the glycosylation reaction. [ABSTRACT FROM AUTHOR]

Although doping can induce room‐temperature phosphorescence (RTP) in heavy‐atom free organic systems, it is often challenging to match the host and guest components to achieve efficient intersystem crossing for activating RTP. In this work, we developed a simple descriptor ΔE to predict host molecules for matching the guest RTP emitters, based on the intersystem crossing via higher excited states (ISCHES) mechanism. This descriptor successfully predicted five commercially available host components to pair with naphthalimide (NA) and naphtho[2,3‐c]furan‐1,3‐dione (2,3‐NA) emitters with a high accuracy of 83 %. The yielded pairs exhibited bright yellow and green RTP with the quantum efficiency up to 0.4 and lifetime up to 1.67 s, respectively. Using these RTP pairs, we successfully achieved multi‐layer message encryption. The ΔE descriptor could provide an efficient way for developing doping‐induced RTP materials. [ABSTRACT FROM AUTHOR]

Keywords: Heterogeneous Catalysis; Hydrophobic Effect; NMR Spectroscopy; Water; ZeoliteZeolites. In their Research Article (e202313974), Jun Xu, Feng Deng et al. identified micro‐hydrophobic effects in benzene methylation over ZSM‐5 zeolite by using solid‐state NMR coupled with ultrahigh magic angle spinning technique and theoretical simulations...By Chao Wang; Yueying Chu; Danfeng Xiong; Haifeng Wang; Min Hu; Qiang Wang; Jun Xu and Feng DengReported by Author; Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

Carbocations such as cyclic carbenium ions are important intermediates in the zeolite‐catalyzed methanol‐to‐olefins (MTO) reaction. The MTO reaction propagates through a complex hydrocarbon pool process. Understanding the carbocation‐involved hydrocarbon pool reaction on a molecular level still remains challenging. Here we show that electron‐deficient cyclopentenyl cations stabilized in ZSM‐5 zeolite are able to capture the alkanes, methanol, and olefins produced during MTO reaction via noncovalent interactions. Intermolecular spatial proximities/interactions are identified by using two‐dimensional 13C–13C correlation solid‐state NMR spectroscopy. Combined NMR experiments and theoretical analysis suggests that in addition to the dispersion and CH/π interactions, the multiple functional groups in the cyclopentenyl cations produce strong attractive force via cation‐induced dipole, cation–dipole and cation–π interactions. These carbocation‐induced noncovalent interactions modulate the product selectivity of hydrocarbon pool reaction. [ABSTRACT FROM AUTHOR]

Although super‐resolution imaging offers an opportunity to visualize cellular structures and organelles at the nanoscale level, cellular heterogeneity and unpredictability still pose a significant challenge in the dynamic imaging of live cells. It is thus vital to develop better‐performing and more photostable probes for long‐term super‐resolution imaging. Herein, we report a probe, LD‐FG, for imaging lipid droplet (LD) dynamics using structured illumination microscopy (SIM). LD‐FG allows wash‐free imaging of LDs, owing to a hydrogen‐bond sensitive fluorogenic response. The replacement of photobleached LD‐FG by intact probe molecules outside the LDs ensures the long‐time stability of the fluorescence imaging. With this buffering fluorogenic probe, fast and unpredictable dynamic processes of LDs can be visualized. Using this probe, two LD coalescence modes were discovered. The dynamic imaging also allowed us to propose a new model of LD maturation during adipocyte differentiation, i.e. a fast LD coalescence followed by a slow ripening step. The excellent performance of LD‐FG makes the buffer strategy an effective method for designing fluorescent probes for cell dynamic imaging. [ABSTRACT FROM AUTHOR]

Propane aromatization on metal‐modified zeolites provides a promising route to produce valuable chemicals such as benzene, toluene and xylene via non‐petroleum feedstocks. The mechanistic understanding of propane conversion to aromatics is still challenging due to the complexity of the aromatization process. Herein, by using solid‐state NMR spectroscopy and GC‐MS, it is shown that cyclopentenyl cations are formed as active intermediates during propane aromatization on Ga/ZSM‐5 zeolite. Autocatalysis of propane to aromatics is identified in the induction period. The cyclopentenyl cations serve as key hydrocarbon pool species to co‐catalyze propane conversion and promote aromatics formation, revealing a dominant hydrocarbon pool process in propane aromatization. [ABSTRACT FROM AUTHOR]

Controllably regulating the electrostatic bilayer of nanogold colloids is a significant premise for synthesizing spherical nucleic acid (SNA) and building ordered plasmonic architectures. We develop a facile acoustic levitation reactor to universally synthesize SNAs with an ultra‐high density of DNA strands, which is even higher than those of various state‐of‐the‐art methods. Results reveal a new mechanism of DNA grafting via acoustic wave that can reconfigure the ligands on colloidal surfaces. The acoustic levitation reactor enables substrate‐free three‐dimentional (3D) spatial assembly of SNAs with controllable interparticle nanogaps through regulating DNA lengths. This kind of architecture may overcome the plasmonic enhancement limits by blocking electron tunneling and breaking electrostatic shielding in dried aggregations. Finite element simulations support the architecture with 3D spatial plasmonic hotspot matrix, and its ultrahigh surface‐enhanced Raman scattering (SERS) capability is evidenced by in situ untargeted tracking of biomolecular events during photothermal stimulation (PTS)‐induced cell death process. For biomarker diagnosis, the conjugation of adenosine triphosphate (ATP) aptamer onto SNAs enables in situ targeted tracking of ATP during PTS‐induced cell death process. Particularly, the CD71 receptor and integrin α3β1 protein on PL45 cell membrance could be well distinguished by label‐free SERS fingerprints when using specific XQ‐2d and DML‐7 aptamers, respectively, to synthesize SNA architectures. Our current acoustic levitation reactor offers a new method for synthesizing SNAs and enables both targeted and untargeted SERS analysis for tracking molecular events in living systems. It promises great potentials in biochemical synthesis and sensing in future. [ABSTRACT FROM AUTHOR]

Single‐atom‐layer catalysts with fully activated basal‐atoms will provide a solution to the low loading‐density bottleneck of single‐atom catalysts. Herein, we activate the majority of the basal sites of monolayer MoS2, by doping Co ions to induce long‐range ferromagnetic order. This strategy, as revealed by in situ synchrotron radiation microscopic infrared spectroscopy and electrochemical measurements, could activate more than 50 % of the originally inert basal‐plane S atoms in the ferromagnetic monolayer for the hydrogen evolution reaction (HER). Consequently, on a single monolayer of ferromagnetic MoS2 measured by on‐chip micro‐cell, a current density of 10 mA cm−2 could be achieved at the overpotential of 137 mV, corresponding to a mass activity of 28, 571 Ag−1, which is two orders of magnitude higher than the multilayer counterpart. Its exchange current density of 75 μA cm−2 also surpasses most other MoS2‐based catalysts. Experimental results and theoretical calculations show the activation of basal plane S atoms arises from an increase of electronic density around the Fermi level, promoting the H adsorption ability of basal‐plane S atoms. [ABSTRACT FROM AUTHOR]

Herein, we report arylazopyrazole ureas and sulfones as a novel class of photoswitchable serine hydrolase inhibitors and present a chemoproteomic platform for rapid discovery of optically controlled serine hydrolase targets in complex proteomes. Specifically, we identify highly potent and selective photoswitchable inhibitors of the drug‐metabolizing enzymes carboxylesterases 1 and 2 and demonstrate their pharmacological application by optically controlling the metabolism of the immunosuppressant drug mycophenolate mofetil. Collectively, this proof‐of‐concept study provides a first example of photopharmacological tools to optically control drug metabolism by modulating the activity of a metabolizing enzyme. Our arylazopyrazole ureas and sulfones offer synthetically accessible scaffolds that can be expanded to identify specific photoswitchable inhibitors for other serine hydrolases, including lipases, peptidases, and proteases. Our chemoproteomic platform can be applied to other photoswitches and scaffolds to achieve optical control over diverse protein classes. [ABSTRACT FROM AUTHOR]

Controlling the self‐assembly morphology of π‐conjugated block copolymer is of great interesting. Herein, amphiphilic poly(3‐hexylthiophene)‐block‐poly(phenyl isocyanide)s (P3HT‐b‐PPI) copolymers composed of π‐conjugated P3HT and optically active helical PPI segments were readily prepared. Taking advantage of the crystallizable nature of P3HT and the chirality of the helical PPI segment, crystallization‐driven asymmetric self‐assembly (CDASA) of the block copolymers lead to the formation of single‐handed helical nanofibers with controlled length, narrow dispersity, and well‐defined helicity. During the self‐assembly process, the chirality of helical PPI was transferred to the supramolecular assemblies, giving the helical assemblies large optical activity. The single‐handed helical assemblies of the block copolymers exhibited interesting white‐light emission and circularly polarized luminescence (CPL). The handedness and dissymmetric factor of the induced CPL can be finely tuned through the variation on the helicity and length of the helical nanofibers. [ABSTRACT FROM AUTHOR]

The shape of eukaryotic cells is determined by the cytoskeleton associated with membrane proteins; however, the detailed mechanism of how the integral morphologies with structural stability is generated and maintained is still not fully understood. Here, based on the Frame‐Guided Assembly (FGA) strategy, we successfully prepared hetero‐liposomes with structural composition similar to that of eukaryotic cells by screening a series of transmembrane peptides as the leading hydrophobic groups (LHGs). It was demonstrated that the conformation and transmembrane mode of the LHGs played dominant roles during the FGA process. The FGA liposomes were formed with excellent stability, which may further provide evidence for the cytoskeleton–membrane protein–lipid bilayer model. Taking advantage of the biocompatibility and stability, the FGA liposomes were also applied to prepare novel drug delivery vehicles, which is promising in diagnostic imaging and cancer therapy applications. [ABSTRACT FROM AUTHOR]

Polar molecular crystals, with their densely stacked polar nonlinear optical (NLO) active units, are favored for their large second harmonic generation (SHG) responses and birefringence. However, their potential for practical applications as Infrared (IR) NLO materials has historically been underappreciated due to the weak inter‐molecular interaction forces that may compromise their physicochemical properties. In this study, we propose molecular crystals with polar molecular cages as a treasure‐house for the development of superior IR NLO materials and a representative system, binary chalcogenide molecular crystals, composed of [P4Sn] (n=3–9) polar molecular cages, is introduced. These crystals may not only achieve wide band gap, large SHG response, and birefringence in a single structure, but also exhibit favorable physicochemical properties. We subsequently obtained a polar molecular crystal, α‐P4S5, which demonstrated exceptional IR optical properties, including a strong SHG response (1.1×AGS), wide band gap (3.02 eV), large birefringence (0.134@2050 nm), and a broad transmission range (0.41–14.7 μm). Moreover, it showed excellent water resistance and hardness. These findings highlight the potential of polar molecular crystals as a promising platform for the development of high‐performance IR NLO materials. [ABSTRACT FROM AUTHOR]

A pyrene‐fused dimerized electron acceptor has been successfully synthesized and subsequently incorporated as the third component in ternary organic solar cells (OSCs). Diverging from the traditional dimerized acceptors with a linear configuration, this novel electron acceptor displays a distinctive "butterfly‐like" structure, comprising two Y‐acceptors as wings fused with a pyrene‐based backbone. The extended π‐conjugated backbone and the electron‐donating nature of pyrene enable the new acceptor to show low solubility, elevated glass transition temperature (Tg), and low‐lying frontier energy levels. Consequently, the new dimerized acceptor seamlessly integrates as the third component into ternary OSCs, enhancing electron transporting properties, reducing non‐radiative voltage loss, and elevating open‐circuit voltage. These merits have enabled the ternary OSCs to show an exceptional efficiency of 19.07%, a marked improvement compared to the 17.6% attained in binary OSCs. More importantly, the high Tg exhibited by the pyrene‐fused electron acceptor helps to stabilize the morphology of the photoactive layer thermal‐treated at 70 °C, retaining 88.7% efficiency over 600 hours. For comparison, binary OSCs experience a decline to 73.7% efficiency after the same duration. These results indicate that the "butterfly‐like" design and the incorporation of a pyrene unit is a promising strategy in the development of dimerized electron acceptors for OSCs. [ABSTRACT FROM AUTHOR]

Inhibition of TICT can significantly increase the brightness of fluorescent materials. Accurate prediction of TICT is thus critical for the quantitative design of high‐performance fluorophores and AIEgens. TICT of 14 types of popular organic fluorophores were modeled with time‐dependent density functional theory (TD‐DFT). A reliable and generalizable computational approach for modeling TICT formations was established. To demonstrate the prediction power of our approach, we quantitatively designed a boron dipyrromethene (BODIPY)‐based AIEgen which exhibits (almost) barrierless TICT rotations in monomers. Subsequent experiments validated our molecular design and showed that the aggregation of this compound turns on bright emissions with ca. 27‐fold fluorescence enhancement, as TICT formation is inhibited in molecular aggregates. [ABSTRACT FROM AUTHOR]

Disclosed herein is the visible‐light‐promoted deaminative C(sp3)−H alkylation of glycine and peptides using Katritzky salts as electrophiles. Simple reaction conditions and excellent functional‐group tolerance provide a general strategy for the efficient preparation of unnatural α‐amino acids and precise modification of peptides with unnatural α‐amino‐acid residues. Mechanistic studies suggest that visible‐light‐promoted intermolecular charge transfer within a glycine–Katritzky salt electron donor‐acceptor (EDA) complex induces a single‐electron transfer process without the assistance of photocatalyst. [ABSTRACT FROM AUTHOR]

The understanding of catalyst deactivation represents one of the major challenges for the methanol‐to‐hydrocarbon (MTH) reaction over acidic zeolites. Here we report the critical role of intermolecular π‐interactions in catalyst deactivation in the MTH reaction on zeolites H‐SSZ‐13 and H‐ZSM‐5. π‐interaction‐induced spatial proximities between cyclopentenyl cations and aromatics in the confined channels and/or cages of zeolites are revealed by two‐dimensional solid‐state NMR spectroscopy. The formation of naphtalene as a precursor to coke species is favored due to the reaction of aromatics with the nearby cyclopentenyl cations and correlates with both acid density and zeolite topology. [ABSTRACT FROM AUTHOR]

This work reports this first synthesis of 1D orthomorphic NH4PbI3 perovskite nanocrystals (NCs) considering the role of inorganic ammonium ions at the nanoscale. The addition of bromide ions at the halogen site did not improve the photoluminescence properties. Furthermore, the 3D cubic phase of (NH4)0.5Cs0.5Pb(I0.5Br0.5)3 NCs with bright photoluminescence was synthesized by adding Cs ions into the crystal lattice of (NH4)Pb(I0.5Br0.5)3. Moreover, the photophysical properties of different phase structures were studied using femtosecond transient absorption (FTA) spectroscopy. The ultrafast trap state capture process is a key factor in the change of photoluminescence properties and the cubic phase may be the best structure for photoluminescence. These results suggest that the ammonium ion perovskite (AIP) nanocrystals could be potential materials for optoelectronic applications through A‐site cation substitution. [ABSTRACT FROM AUTHOR]

This work reports this first synthesis of 1D orthomorphic NH4PbI3 perovskite nanocrystals (NCs) considering the role of inorganic ammonium ions at the nanoscale. The addition of bromide ions at the halogen site did not improve the photoluminescence properties. Furthermore, the 3D cubic phase of (NH4)0.5Cs0.5Pb(I0.5Br0.5)3 NCs with bright photoluminescence was synthesized by adding Cs ions into the crystal lattice of (NH4)Pb(I0.5Br0.5)3. Moreover, the photophysical properties of different phase structures were studied using femtosecond transient absorption (FTA) spectroscopy. The ultrafast trap state capture process is a key factor in the change of photoluminescence properties and the cubic phase may be the best structure for photoluminescence. These results suggest that the ammonium ion perovskite (AIP) nanocrystals could be potential materials for optoelectronic applications through A‐site cation substitution. [ABSTRACT FROM AUTHOR]

The generation of singlet oxygen (1O2) during photodynamic therapy is limited by the precise cooperation of light, photosensitizer, and oxygen, and the therapeutic efficiency is restricted by the elevated glutathione (GSH) levels in cancer cells. Herein, we report that an ultrathin two‐dimensional metal–organic framework of Cu‐TCPP nanosheets (TCPP=tetrakis(4‐carboxyphenyl)porphyrin) can selectively generate 1O2 in a tumor microenvironment. This process is based on the peroxidation of the TCPP ligand by acidic H2O2 followed by reduction to peroxyl radicals under the action of the peroxidase‐like nanosheets and Cu2+, and their spontaneous recombination reaction by the Russell mechanism. In addition, the nanosheets can also deplete GSH. Consequently, the Cu‐TCPP nanosheets can selectively destroy tumor cells with high efficiency, constituting an attractive way to overcome current limitations of photodynamic therapy. [ABSTRACT FROM AUTHOR]

In the rapidly developing smart era, near‐infrared luminescent materials have important applications in various fields that are closely related to people. Nag and co‐workers provided a first codoping strategy to achieve efficient near‐infrared photoluminescence in lead‐free double perovskite materials. Through the introduction of Bi3+ ions, a new energy state is formed that leads to the absorption of lower‐energy light. The excited state formed by this light absorption subsequently excites f‐electrons of Er3+ or Yb3+ ions, and the relaxation of these f‐electrons results in near‐infrared photoluminescence. This may open a new chapter in the application of perovskites for infrared detection and human sensing. [ABSTRACT FROM AUTHOR]

Despite a well‐developed and growing body of work in Cu catalysis, the potential of Cu to serve as a photocatalyst remains underexplored. Reported herein is the first example of visible‐light‐induced Cu‐catalyzed decarboxylative C(sp3)−H alkylation of glycine for preparing α‐alkylated unnatural α‐amino acids. It merits mentioning that the mild conditions and the good functional‐group tolerance allow the modification of peptides using this method. The mechanistic studies revealed that a radical–radical coupling pathway is involved in the reaction. Out of the clear blue: The title reaction was developed for preparing α‐alkylated non‐natural α‐amino acids by transformation of glycine moieties. Mild conditions and good functional‐group tolerance allow the modification of peptides using this method. Mechanistic studies revealed that a radical–radical coupling pathway is involved in the reaction. [ABSTRACT FROM AUTHOR]

Abstract: Surface methoxy species bound to an extra‐framework Al (SMS‐EFAL) was unambiguously identified by advanced 13C‐{27Al} double‐resonance solid‐state NMR technique in the methanol‐to‐olefins reaction on H‐ZSM‐5 zeolite. The high reactivity of the SMS‐EFAL leads to the formation of surface ethoxy species and ethanol as the key intermediates for ethene generation in the early reaction stage. A direct route for the initial C−C bond formation in ethene was proposed and corroborated by density functional theory calculations. [ABSTRACT FROM AUTHOR]

Abstract: Precise control of the molecular arrangements at the interface between the electron donor and acceptor in mixed bulk heterojunctions (BHJs) remains challenging, despite the correlation between structural characteristics and efficiency in organic photovoltaics (OPVs). This study reveals that the substitution patterns of linear and branched alkyl side chains on electron‐donating/‐accepting alternating copolymers can control the positions of an acceptor molecule (C60) around the π‐conjugated main chains in mixed BHJs. Two‐dimensional solid‐state NMR demonstrates a marked difference in the location of C60 in the blend films. A copolymer with an electron‐accepting unit positioned in close proximity to C60 demonstrated higher OPV performance in combination with various fullerene derivatives. This molecular design offers precise control over the interfacial molecular structure, thereby paving the way for overcoming the current limitations of OPVs comprising mixed BHJs. [ABSTRACT FROM AUTHOR]

Abstract: The growth of lithium dendrites and low coulombic efficiency restrict the development of Li metal anodes. Polymer electrolytes are expected to be promising candidates to solve the issue, but ways to obtain a polymer electrolyte that integrates high ionic conductivity and high mechanical toughness is still challenging. By introducing a double polymer network into the electrolyte design to reshape it, a tough polymer electrolyte was developed with high conductivity, and stable operation of lithium metal anodes was further realized. The double network (DNW) gel electrolyte has high modulus of 44.3 MPa and high fracture energy of 69.5 kJ m−2. The conductivity of DNW gel is 0.81 mS cm−1 at 30 °C. By using this gel electrolyte design, the lithium metal electrode could be cycled more than 400 times with a coulombic efficiency (CE) as high as 96.3 % with carbonate‐based electrolytes. [ABSTRACT FROM AUTHOR]

Double perovskites (DP) have attracted extensive attention due to their rich structures and wide application prospects in the field of optoelectronics. Here, we report 15 new Bi‐based double perovskite derived halides with the general formula of A2BBiX6 (A=organic cationic ligand, B=K or Rb, X=Br or I). These materials are synthesized using organic ligands to coordinate with metal ions with a sp3 oxygen, and diverse structure types have been obtained with distinct dimensionalities and connectivity modes. The optical band gaps of these phases can be tuned by changing the halide, the organic ligand and the alkali metal, varying from 2.0 to 2.9 eV. The bromide phases exhibit increasing photoluminescence (PL) intensity with decreasing temperature, while the PL intensity of iodide phases changes nonmonotonically with temperature. Because the majority of these phases are non‐centrosymmetric, second harmonic generation (SHG) responses are also measured for selected non‐centrosymmetric materials, showing different particle‐size‐dependent trends. Our findings give rise to a series of new structural types to the DP family, and provide a powerful synthetic handle for symmetry breaking. [ABSTRACT FROM AUTHOR]

A cobalt-catalyzed Z-selective hydrosilylation of alkynes has been developed relying on catalysts generated from bench-stable Co(OAc)2 and pyridine-2,6-diimine (PDI) ligands. A variety of functionalized aromatic and aliphatic alkynes undergo this transformation, yielding Z-vinylsilanes in high yields with excellent selectivities ( Z/ E ratio ranges from 90:10 to >99:1). The addition of a catalytic amount of phenol effectively suppressed the Z/ E-isomerization of the Z-vinylsilanes that formed under catalytic conditions. [ABSTRACT FROM AUTHOR]

We report the development of a Pd-catalyzed process for the cross coupling of unactivated primary, secondary, and tertiary alkylcarbastannatrane nucleophiles with acyl electrophiles. Reactions involving optically active alkylcarbastannatranes occur with exceptional stereofidelity and with net retention of absolute configuration. Because the stereochemistry of the resulting products is entirely reagent-controlled, this process may be viewed as a general, alternative approach to the preparation of products typically accessed via asymmetric enolate methodologies. Additionally, we report a new method for the preparation of optically active alkylcarbastannatranes, which should facilitate their future use in stereospecific reactions. [ABSTRACT FROM AUTHOR]

Anion-π catalysis, that is the stabilization of anionic transition states on π-acidic aromatic surfaces, has so far been developed with naphthalenediimides (NDIs). This report introduces perylenediimides (PDIs) to anion-π catalysis. The quadrupole moment of PDIs (+23.2 B) is found to exceed that of NDIs and reach new records with acceptors in the core (+70.9 B), and their larger surface provides space to better accommodate chemical transformations. Unlike NDIs, the activity of PDI catalysts for enolate and enamine addition is determined by the twist of their π surface rather than their reducibility. These results, further strengthened by nitrate inhibition and circular dichroism spectroscopy, support an understanding of anion-π interactions centered around quadrupole moments, i.e., electrostatic contributions, rather than redox potentials and charge transfer. The large PDI surfaces provide access to the highest enantioselectivities observed so far in anion-π catalysis (96 % ee). [ABSTRACT FROM AUTHOR]

11-Saxitoxinethanoic acid (SEA) is a member of the saxitoxin (STX) family of paralytic shellfish poisons, and contains an unusual C−C bond at the C11 position. Reported herein is a total synthesis of SEA. The key to our synthesis lies in a Mukaiyama aldol condensation reaction of silyl enol ether with glyoxylate in the presence of an anhydrous fluoride reagent, [Bu4N][Ph3SnF2], which directly constructs the crucial C−C bond at the C11 position in SEA. The NaVCh-inhibitory activities of SEA and its derivatives were evaluated by means of cell-based assay. SEA showed an IC50 value of (47±12) n m, which is approximately twice as potent as decarbamoyl-STX (dcSTX). [ABSTRACT FROM AUTHOR]

Development of chemically doped high performance n-type organic thermoelectric (TE) materials is of vital importance for flexible power generating applications. For the first time, bismuth (Bi) n-type chemical doping of organic semiconductors is described, enabling high performance TE materials. The Bi interfacial doping of thiophene-diketopyrrolopyrrole-based quinoidal (TDPPQ) molecules endows the film with a balanced electrical conductivity of 3.3 S cm−1 and a Seebeck coefficient of 585 μV K−1. The newly developed TE material possesses a maximum power factor of 113 μW m−1 K−2, which is at the forefront for organic small molecule-based n-type TE materials. These studies reveal that fine-tuning of the heavy metal doping of organic semiconductors opens up a new strategy for exploring high performance organic TE materials. [ABSTRACT FROM AUTHOR]

We present a novel chemical scaffold for cysteine-reactive covalent inhibitors. Chloromethyl triazoles (CMTs) are readily accessed in only two chemical steps, thus enabling the rapid optimization of the pharmacological properties of these inhibitors. We demonstrate the tunability of the CMTs towards a specific biological target by synthesizing AA-CW236 as the first potent non-pseudosubstrate inhibitor of the O6-alkylguanine DNA methyltransferase (MGMT), a protein of major clinical significance for the treatment of several severe cancer forms. Using quantitative proteomics profiling techniques, we show that AA-CW236 exhibits a high degree of selectivity towards MGMT. Finally, we validate the effectiveness of our MGMT inhibitor in combination with the DNA alkylating drug temozolomide in breast and colon cancer cells by fluorescence imaging and a cell-viability assay. Our results may open a new avenue towards the development of a clinically approved MGMT inhibitor. [ABSTRACT FROM AUTHOR]

Hydrocarbon-pool chemistry is important in methanol to olefins (MTO) conversion on acidic zeolite catalysts. The hydrocarbon-pool (HP) species, such as methylbenzenes and cyclic carbocations, confined in zeolite channels during the reaction are essential in determining the reaction pathway. Herein, we experimentally demonstrate the formation of supramolecular reaction centers composed of organic hydrocarbon species and the inorganic zeolite framework in H-ZSM-5 zeolite by advanced 13C-27Al double-resonance solid-state NMR spectroscopy. Methylbenzenes and cyclic carbocations located near Brønsted acid/base sites form the supramolecular reaction centers in the zeolite channel. The internuclear spatial interaction/proximity between the 13C nuclei (associated with HP species) and the 27Al nuclei (associated with Brønsted acid/base sites) determines the reactivity of the HP species. The closer the HP species are to the zeolite framework Al, the higher their reactivity in the MTO reaction. [ABSTRACT FROM AUTHOR]

An easily synthesized and accessible N,O-bidentate auxiliary has been developed for selective CH activation under palladium catalysis. The novel auxiliary showed its first powerful application in CH functionalization of remote positions. Both C(sp2)H and C(sp3)H bonds at δ- and ε-positions were effectively activated, thus giving tetrahydroquinolines, benzomorpholines, pyrrolidines, and indolines in moderate to excellent yields by palladium-catalyzed intramolecular CH amination. [ABSTRACT FROM AUTHOR]

The anticancer natural product simaomicin α has been synthesized. Asymmetric synthesis allowed the assignment of absolute stereochemistry. The enantiomer of the naturally occurring substance shows potent cytotoxicity towards Gram‐positive bacteria and human cancer cells. Bn=benzyl, BOM=benzyloxymethyl. [ABSTRACT FROM AUTHOR]

Carbocations, methanol conversion, noncovalent interactions, solid-state NMR spectroscopy, zeolites Keywords: carbocations; methanol conversion; noncovalent interactions; solid-state NMR spectroscopy; zeolites EN carbocations methanol conversion noncovalent interactions solid-state NMR spectroscopy zeolites 26413 26413 1 12/07/21 20211213 NES 211213 B Cyclic carbocations b are important intermediates in methanol-to-olefins (MTO) reaction over zeolite. Cover Picture: Insight into Carbocation-Induced Noncovalent Interactions in the Methanol-to-Olefins Reaction over ZSM-5 Zeolite by Solid-State NMR Spectroscopy (Angew. [Extracted from the article]

Electrochemical C−N coupling reaction based on carbon dioxide and nitrate have been emerged as a new "green synthetic strategy" for the synthesis of urea, but the catalytic efficiency is seriously restricted by the inherent scaling relations of adsorption energies of the active sites, the improvement of catalytic activity is frequently accompanied by the decrease in selectivity. Herein, a doping engineering strategy was proposed to break the scaling relationship of intermediate binding and minimize the kinetic barrier of C−N coupling. A thus designed SrCo0.39Ru0.61O3−δ catalyst achieves a urea yield rate of 1522 μg h−1 mgcat.−1 and faradic efficiency of 34.1 % at −0.7 V versus reversible hydrogen electrode. A series of characterizations revealed that Co doping not only induces lattice distortion but also creates rich oxygen vacancies (OV) in the SrRuO3. The oxygen vacancies weaken the adsorption of *CO and *NH2 intermediates on the Co and Ru sites respectively, and the strain effects over the Co−Ru dual sites promoting the occurrence of C−N coupling of the two monomers instead of selective hydrogenating to form by‐products. This work presents an insight into molecular coupling reactions towards urea synthesis via the doping engineering on SrRuO3. [ABSTRACT FROM AUTHOR]

LiNO3 is a remarkable additive that can dramatically enhance the stability of ether‐based electrolytes at lithium metal anodes. However, it has long been constrained by its incompatibility with commercially used ester electrolytes. Herein, we correlated the fundamental role of entropy with the limited LiNO3 solubility and proposed a new low‐entropy‐penalty design that achieves high intrinsic LiNO3 solubility in ester solvents by employing multivalent linear esters. This strategy is conceptually different from the conventional enthalpic methods that relies on extrinsic high‐polarity carriers. In this way, LiNO3 can directly interact with the primary ester solvents and fundamentally alters the electrolyte properties, resulting in substantial improvements in lithium‐metal batteries with high Coulombic efficiency and cycling stability. This work illustrates the significance of regulating the solvation entropy for high‐performance electrolyte design. [ABSTRACT FROM AUTHOR]

Cheap, stable and easy‐to‐handle Werner ammine salts have been known for more than a century; but they have been rarely used in organic synthesis. Herein, we report that the Werner hexammine complex [Ni(NH3)6]Cl2 can be used as both a nitrogen and a catalytic nickel source that allow for the efficient amination of aryl chlorides in the presence of a catalytic amount of bipyridine ligand under the irradiation of 390–395 nm light without the need of any additional catalysts. More than 80 aryl chlorides, including more than 20 drug molecules, were aminated, demonstrating the practicality and generality of this method in synthetic chemistry. A slow NH3 release mechanism is in operation, obviating the problem of catalyst poisoning. Still interestingly, we show that the Werner salt can be easily recovered and reused, solving the problem of difficult recovery of transition metal nickel catalysts. The protocol thus provides an efficient new strategy for the synthesis of primary aryl amines. [ABSTRACT FROM AUTHOR]

The engagement of unactivated alkyl halides in copper‐catalyzed cross‐coupling reactions has been historically challenging, due to their low reduction potential and the slow oxidative addition of copper(I) catalysts. In this work, we report a novel strategy that leverages the halogen abstraction ability of aryl radicals, thereby engaging a diverse range of alkyl iodides in copper‐catalyzed Negishi‐type cross‐coupling reactions at room temperature. Specifically, aryl radicals generated via copper catalysis efficiently initiate the cleavage of the carbon–iodide bonds of alkyl iodides. The alkyl radicals thus generated enter the copper catalytic cycles to couple with a difluoromethyl zinc reagent, thus furnishing the alkyl difluoromethane products. This unprecedented Negishi‐type difluoromethylation approach has been applied to the late‐stage modification of densely functionalized pharmaceutical agents and natural products. [ABSTRACT FROM AUTHOR]

The incorporation of insulating polymers into conjugated polymers has been widely explored as a strategy to improve mechanical properties of flexible organic electronics. However, phase separation due to the immiscibility of these polymers has limited their effectiveness. In this study, we report the discovery of multiple non‐covalent interactions that enhances the miscibility between insulating and conjugated polymers, resulting in improved mechanical properties. Specifically, we have added polyvinyl chloride (PVC) into the conjugated polymer PM6 and observed a significant increase in solution viscosity, indicative of favorable miscibility between these two polymers. This phenomenon has been rarely observed in other insulating/conjugated polymer composites. Thin films of PM6/PVC exhibit a much‐improved crack‐onset strain of 19.35 %, compared to 10.12 % for pristine PM6 films. Analysis reveal that a "cyclohexyl‐like" structure formed through dipole‐dipole interactions and hydrogen bonding between PVC and PM6 acted as a cross‐linking site in the thin films, leading to improved mechanical properties. Moreover, PM6/PVC blend films have demonstrated excellent thermal and bending stability when applied as an electron donor in organic solar cells. These findings provide new insights into non‐covalent interactions that can be utilized to enhance the properties of conjugated polymers and may have potential applications in flexible organic electronics. [ABSTRACT FROM AUTHOR]

Discovering the underlying reason for Li anode failure is a critical step towards applications of lithium metal batteries (LMBs). In this work, we conduct deuterium‐oxide (D2O) titration experiments in a novel on‐line gas analysis mass spectrometry (MS) system, to determine the content of metallic Li and lithium hydride (LiH) in cycled Li anodes disassembled from practical LiCoO2/Li LMBs. The practical cell is comprised of ultrathin Li anode (50 μm), high loading LiCoO2 (17 mg cm−2, 2.805 mAh cm−2) and different formulated electrolytes. Our results suggest that the amount of LiH accumulation is negatively correlated with cyclability of practical LMBs. More importantly, we reveal a temperature sensitive equilibrium (Li + 1/2 H2 ⇌ LiH) governing formation and decomposition process of LiH at Li anode. We believe that the unusual understanding provided by this study will draw forth more insightful efforts to realize efficient Li protection and the ultimate applications of "holy grail" LMBs. [ABSTRACT FROM AUTHOR]

Herein, we reported a simple, fast, and quantitative theoretical descriptor ΔGC‐O that allows accurate predictions of a wide range of spontaneously blinking rhodamines. ΔGC‐O denotes the Gibbs free energy differences between the closed and open forms of rhodamines and has a good linear relationship with experimental pKcycl values. This correlation affords an effective guide for the quantitative designs of spontaneously blinking rhodamines and eliminates trial‐and‐error. We have validated the predictive power of ΔGC‐O via the development of two spontaneously blinking rhodamines of different colors and enhanced brightness. We also demonstrated their super‐resolution imaging utilities in dynamic live‐cell imaging. We expect that ΔGC‐O will greatly facilitate the efficient creations of spontaneously blinking fluorophores and aid the advancements of super‐resolution bioimaging techniques. [ABSTRACT FROM AUTHOR]