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2D conjugated metal–organic frameworks (2D c‐MOFs) are emerging as electroactive materials for chemiresistive sensors, but selective sensing with fast response/recovery is a challenge. Phthalocyanine‐based Ni2[MPc(NH)8] 2D c‐MOF films are presented as active layers for polarity‐selective chemiresisitors toward water and volatile organic compounds (VOCs). Surface‐hydrophobic modification by grafting aliphatic alkyl chains on 2D c‐MOF films decreases diffused analytes into the MOF backbone, resulting in a considerably accelerated recovery progress (from ca. 50 to ca. 10 s) during humidity sensing. Toward VOCs, the sensors deliver a polarity‐selective response among alcohols but no signal for low‐polarity aprotic hydrocarbons. The octadecyltrimethoxysilane‐modified Ni2[MPc(NH)8] based sensor displays high‐performance methanol sensing with fast response (36 s)/recovery (13 s) and a detection limit as low as 10 ppm, surpassing reported room‐temperature chemiresistors. [ABSTRACT FROM AUTHOR]

Producing renewable biofuels from biomass is a promising way to meet future energy demand. Here, we demonstrated a lignin to diesel route via dimerization of the lignin oil followed by hydrodeoxygenation. The lignin oil undergoes C−C bond dehydrogenative coupling over Au/CdS photocatalyst under visible light irradiation, co‐generating diesel precursors and hydrogen. The Au nanoparticles loaded on CdS can effectively restrain the recombination of photogenerated electrons and holes, thus improving the efficiency of the dimerization reaction. About 2.4 mmol gcatal−1 h−1 dimers and 1.6 mmol gcatal−1 h−1 H2 were generated over Au/CdS, which is about 12 and 6.5 times over CdS, respectively. The diesel precursors are finally converted into C16–C18 cycloalkanes or aromatics via hydrodeoxygenation reaction using Pd/C or porous CoMoS catalyst, respectively. The conversion of pine sawdust to diesel was performed to demonstrate the feasibility of the lignin‐to‐diesel route. [ABSTRACT FROM AUTHOR]

Deep‐penetration fluorescence imaging in the second near‐infrared (NIR‐II) window heralds a new era of clinical surgery, in which high‐resolution vascular/lymphatic anatomy and detailed cancerous tissues can be visualized in real time. Described here is a series of polymethine‐based semiconducting polymers with intrinsic emission maxima in the NIR‐IIa (1300–1400 nm) window and absorption maxima ranging from 1082 to 1290 nm. These polymers were prepared as semiconducting polymer dots (Pdots) in aqueous solutions with fluorescence quantum yields of 0.05–0.18 %, and they demonstrate promising applications in noninvasive through‐skull brain imaging in live mice with remarkable spatial resolution as well as signal‐to‐background contrast. This study offers a platform for future design of NIR‐IIa or even NIR‐IIb emitting Pdots. [ABSTRACT FROM AUTHOR]

Fluorescence probes in the NIR‐IIa region show drastically improved imaging owing to the reduced photon scattering and autofluorescence in biological tissues. Now, NIR‐IIa polymer dots (Pdots) are developed with a dual fluorescence enhancement mechanism. First, the aggregation induced emission of phenothiazine was used to reduce the nonradiative decay pathways of the polymers in condensed states. Second, fluorescence quenching was minimized by different levels of steric hindrance to further boost the fluorescence. The resulting Pdots displayed a fluorescence QY of ca. 1.7 % in aqueous solution, suggesting an enhancement of ca. 21 times in comparison with the original polymer in tetrahydrofuran (THF) solution. Small‐animal imaging by using the NIR‐IIa Pdots exhibited a remarkable improvement in penetration depth and signal to background ratio, as confirmed by through‐skull and through‐scalp fluorescent imaging of the cerebral vasculature of live mice. [ABSTRACT FROM AUTHOR]

Two- and three-dimensional metallosupramolecules shaped like a Star of David were synthesized by the self-assembly of a tetratopic pyridyl ligand with a 180° diplatinum(II) motif and PdII ions, respectively. In contrast to other strategies, such as template-directed synthesis and stepwise self-assembly, this design enables the formation of 2D and 3D structures in one step and high yield. The structures were characterized by both one-dimensional (1H, 13C, 31P) and two-dimensional (COSY, NOESY, DOSY) NMR spectroscopy, ESI-MS, ion-mobility mass spectrometry (IM-MS), AFM, and TEM. The stabilities of the 2D and 3D structures were measured and compared by gradient tandem mass spectrometry (gMS2). The high stability of the 3D Star of David was correlated to its high density of coordination sites (DOCS). [ABSTRACT FROM AUTHOR]

α-Fluorocarbanions are key intermediates in nucleophilic fluoroalkylation reactions. Although frequently discussed, the origin of the fluorine effect on the reactivity of α-fluorinated CH acids has remained largely unexplored. We have now investigated the kinetics of a series of reactions of α-substituted carbanions with reference electrophiles to elucidate the effects of α-F, α-Cl, and α-OMe substituents on the nucleophilic reactivities of carbanions. [ABSTRACT FROM AUTHOR]

The research leading to the results published in this manuscript was also supported by the project CALIPSOplus under Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020. This corrigendum corrects an omission from the Acknowledgement section. Corrigendum: Surface-Modified Phthalocyanine-Based Two-Dimensional Conjugated Metal-Organic Framework Films for Polarity-Selective Chemiresistive Sensing. [Extracted from the article]

Enantiomers of 2, 6‐diaminotriptycene (R, R‐1 and S, S‐1) are split by chiral‐phase HPLC and their absolute configurations are identified by single‐crystal X‐ray diffraction technology. Using the enantiomers as monomers, a couple of chiral porous polyimides (R‐FTPI and S‐FTPI) are prepared by polycondensation reactions and display good heat stability, high BET surface area and good solubility in organic solvents. Moreover, both of R‐FTPI and S‐FTPI can be cast into robust, free‐standing films suitable for enantioselective separation with symmetrical chiral selectivity. [ABSTRACT FROM AUTHOR]

In the molecular optimizations of non‐fullerene acceptors (NFAs), extending the central core can tune the energy levels, reduce nonradiative energy loss, enhance the intramolecular (donor‐acceptor and acceptor‐acceptor) packing, facilitate the charge transport, and improve device performance. In this study, a new strategy was employed to synthesize acceptors featuring conjugation‐extended electron‐deficient cores. Among these, the acceptor CH‐BBQ, embedded with benzobisthiadiazole, exhibited an optimal fibrillar network morphology, enhanced crystallinity, and improved charge generation/transport in blend films, leading to a power conversion efficiency of 18.94 % for CH‐BBQ‐based ternary organic solar cells (OSCs; 18.19 % for binary OSCs) owing to its delicate structure design and electronic configuration tuning. Both experimental and theoretical approaches were used to systematically investigate the influence of the central electron‐deficient core on the properties of the acceptor and device performance. The electron‐deficient core modulation paves a new pathway in the molecular engineering of NFAs, propelling relevant research forward. [ABSTRACT FROM AUTHOR]

The precise control over hierarchical self‐assembly of superstructures relying on the elaboration of multiple noncovalent interactions between basic building blocks is both elusive and highly desirable. We herein report a terpyridine‐based metallo‐cage T with a tetrahedral motif and utilized it as an efficient building block for the controlled hierarchical self‐assembly of superstructures in response to different halide ions. Initially, the hierarchical superstructure of metallo‐cage T adopted a hexagonal close‐packed structure. By adding Cl−/Br− or I−, drastically different hierarchical superstructures with highly‐tight hexagonal packing or graphite‐like packing arrangements, respectively, have been achieved. These unusual halide‐ion‐triggered hierarchical structural changes resulted in quite distinct intermolecular channels, which provided new insights into the mechanism of three‐dimensional supramolecular aggregation and crystal growth based on macromolecular construction. In addition, the chiral induction of the metallo‐cage T can be realized with the addition of chiral anions, which stereoselectively generated either PPPP‐ or MMMM‐type enantiomers. [ABSTRACT FROM AUTHOR]

The aryl‐to‐vinyl nickel 1,4‐migration (1,4‐Ni migration) reaction has been reported for the first time. The generated alkenyl Ni species undergo a reductive coupling reaction with unactivated brominated alkanes affording a series of trisubstituted olefins. This tandem reaction exhibits mild conditions, a broad substrate scope, high regioselectivity, and excellent Z/E stereoselectivity. A series of controlled experiments have shown that the critical 1,4‐Ni migration process is reversible. In addition, the alkenyl nickel intermediates obtained after migration are highly Z/E stereoselective and do not undergo Z/E isomerization. The obtained trace isomerization products are caused by the instability of the product. [ABSTRACT FROM AUTHOR]

A correction to the article "The Nucleophilicity of Persistent α-Monofluoromethide Anions," by Z. Zhang et al, published in a previous isssue is presented.

Nanofluidic reverse electrodialysis provides an attractive way to harvest osmotic energy. However, most attention was paid to monotonous membrane structure optimization to promote selective ion transport, while the role of external fields and relevant mechanisms are rarely explored. Here, we demonstrate a Kevlar‐toughened tungsten disulfide (WS2) composite membrane with bioinspired serosa‐mimetic structures as an efficient osmotic energy generator coupling light. As a result, the output power could be up to 16.43 W m−2 under irradiation, outperforming traditional two‐dimensional (2D) membranes. Both the experiment and simulation uncover that the generated photothermal and photoelectronic effects could synergistically promote the confined ion transport process. In addition, this membrane also possesses great anti‐fouling properties, endowing its practical application. This work paves new avenues for sustainable power generation by coupling solar energy. [ABSTRACT FROM AUTHOR]

Construction of supramolecular structures with internal functionalities is a promising approach to build enzyme‐like cavities. The endo‐functionalized [Pd12L24] and [Pd2L4] coordination cages represent the most successful systems in this regard. However, these systems mainly contain one type of endo‐moiety. We herein provide a solution for the controlled endo‐functionalization of [Pd2L4] cages. Site‐selective introduction of the endo‐functional group was achieved through the formation of heteroleptic [Pd2(LA)2(LB)(LC)] cages. Using two orthogonal steric control elements is the key for the selective formation of the hetero‐assemblies. We demonstrated the construction of two hetero‐cages with a single internal functional group as well as a hetero‐cage with two distinct endohedral functionalities. The endo‐functionalized hetero‐cages bound sulfonate guests with fast‐exchange dynamics. This strategy provides a new solution for the controlled endo‐functionalization of supramolecular cavities. [ABSTRACT FROM AUTHOR]

Halogenation of terminal of acceptors has been shown to give dramatic improvements in power conversion efficiencies (PCEs) of organic solar cells (OSCs). Similar significant results could be expected from the halogenation of the central units of state‐of‐the‐art Y‐series acceptors. Herein, a pair of acceptors, termed CH6 and CH4, featuring a conjugation‐extended phenazine central unit with and without fluorination, have been synthesized. The fluorinated CH6 has enhanced molecular interactions and crystallinity, superior fibrillar network morphology and improved charge generation and transport in blend films, thus affording a higher PCE of 18.33 % for CH6‐based binary OSCs compared to 16.49 % for the non‐fluorinated CH4. The new central site offers further opportunities for structural optimization of Y‐series molecules to afford better‐performed OSCs and reveals the effectiveness of fluorination on central units. [ABSTRACT FROM AUTHOR]

Organic solvent nanofiltration (OSN) has become increasingly important in petrochemical and pharmaceutical industries, demanding superior and robust membranes. Herein, we report advanced OSN processes by designing three‐dimensional covalent organic framework (3D COF) membranes through moderated interfacial crystallization. Nanoporous supports work as the moderator allowing the crystallization of 3D COF membranes. The 3D COF features sub‐nanometer and anti‐swelling channels, affording a sharp selectivity to fine targets with an exceptionally high and stable methanol permeance. Thus‐synthesized membrane exhibits a record stability against high‐concentration feeds and long‐term operation for ≈1000 h. Moreover, we unambiguously demonstrate that our membrane holds excellent practicality in purifying active pharmaceutical ingredients from organic liquids. This work reveals the great potential of distinctive 3D COFs in producing prominent OSN membranes for industrial applications. [ABSTRACT FROM AUTHOR]

The ability to construct complex molecular architectures with precise control is critical for realizing molecule‐based materials and functions. Using the assembly of a 60‐metal complex of ErIII with histidine as an example, we demonstrate the rational assembly of otherwise synthetically elusive polynuclear lanthanide hydroxide clusters directed by the combined set of I− and CO32− as templates. We succeeded in the stepwise transformation starting from Er12 to Er60 by way of two key intermediates Er34 and Er48. The Er12, Er34, and Er48 core motifs represent respectively 1/6, 1/2, and 3/4 of the complete sodalite cage of Er60. This work, representing a rare example of rationally constructing high‐nuclearity lanthanide clusters guided by judiciously chosen templates, is expected to stimulate more future efforts for the controllable synthesis of complex molecular or supramolecular architectures with unprecedented structural sophistication and possibly useful properties. [ABSTRACT FROM AUTHOR]

The trifluoromethanide anion is the postulated key intermediate in nucleophilic trifluoromethylation reactions. However, for more than six decades, the trifluoromethanide anion was widely believed to exist only as a short-lived transient species in the condensed phase. It has now been prepared in bulk for the first time in THF solution. The trifluoromethanide anion with the [K(18-crown-6)]+ cation was unequivocally characterized by low-temperature 19F and 13C NMR spectroscopy. Its intermediacy in nucleophilic trifluoromethylation reactions was directly evident by its reaction chemistry with various electrophilic substrates. Variable-temperature NMR spectroscopy, along with quantum mechanical calculations, support the persistence of the trifluoromethanide anion. [ABSTRACT FROM AUTHOR]

Here, we describe a fluorination strategy for semiconducting polymers for the development of highly bright second near‐infrared region (NIR‐II) probes. Tetrafluorination yielded a fluorescence QY of 3.2 % for the polymer dots (Pdots), over a 3‐fold enhancement compared to non‐fluorinated counterparts. The fluorescence enhancement was attributable to a nanoscale fluorous effect in the Pdots that maintained the molecular planarity and minimized the structure distortion between the excited state and ground state, thus reducing the nonradiative relaxations. By performing through‐skull and through‐scalp imaging of the brain vasculature of live mice, we quantitatively analyzed the vascular morphology of transgenic brain tumors in terms of the vessel lengths, vessel branches, and vessel symmetry, which showed statistically significant differences from the wild type animals. The bright NIR‐II Pdots obtained through fluorination chemistry provide insightful information for precise diagnosis of the malignancy of the brain tumor. [ABSTRACT FROM AUTHOR]

Traditional methods for analyzing organophosphorus pesticide chlorpyrifos, usually require the tedious sample pretreatment and sophisticated bio‐interfaces, leading to the difficulty for real‐time analysis. Herein, we use palladium single‐atom (PdSA)/TiO2 as a photocatalytic sensing platform to directly detect chlorpyrifos with high sensitivity and selectivity. PdSA/TiO2, prepared by an in situ photocatalytic reduction of PdCl42− on the TiO2, shows much higher photocatalytic activity (10 mol g−1 h−1) for hydrogen evolution reaction than Pd nanoparticles (1.95 mol g−1 h−1), and excellent stability. In the presence of chlorpyrifos, the photocatalytic activity of PdSA/TiO2 decreases. Through this inhibition effect the platform can realize a detection limit for chlorpyrifos of 0.01 ng mL−1, much lower than the maximum residue limit (10 ppb) permitted by the U.S. Environmental Protection Agency. [ABSTRACT FROM AUTHOR]

Anion Template, Clusters, Lanthanides, Polynuclear, Self-Assembly In their Research Article (e202205385), Min Feng, Zhiping Zheng, and co-workers developed a stepwise synthesis of a high-nuclearity sodalite cage-like cluster B Er b SB B 60 b sb , guided by judiciously selected anions. Keywords: Anion Template; Clusters; Lanthanides; Polynuclear; Self-Assembly EN Anion Template Clusters Lanthanides Polynuclear Self-Assembly 1 1 1 08/11/22 20220815 NES 220815 B The rational synthesis b of high-nuclearity lanthanide clusters remains challenging. [Extracted from the article]

Selective oxidative cleavage of a C-C bond offers a straightforward method to functionalize organic skeletons. Reported herein is the oxidative C-C bond cleavage of ketone for C-N bond formation over a cuprous oxide catalyst with molecular oxygen as the oxidant. A wide range of ketones and amines are converted into cyclic imides with moderate to excellent yields. In-depth studies show that both α-C-H and β-C-H bonds adjacent to the carbonyl groups are indispensable for the C-C bond cleavage. DFT calculations indicate the reaction is initiated with the oxidation of the α-C-H bond. Amines lower the activation energy of the C-C bond cleavage, and thus promote the reaction. New insight into the C-C bond cleavage mechanism is presented. [ABSTRACT FROM AUTHOR]

The ability to construct complex molecular architectures with precise control is critical for realizing molecule‐based materials and functions. Using the assembly of a 60‐metal complex of ErIII with histidine as an example, we demonstrate the rational assembly of otherwise synthetically elusive polynuclear lanthanide hydroxide clusters directed by the combined set of I− and CO32− as templates. We succeeded in the stepwise transformation starting from Er12 to Er60 by way of two key intermediates Er34 and Er48. The Er12, Er34, and Er48 core motifs represent respectively 1/6, 1/2, and 3/4 of the complete sodalite cage of Er60. This work, representing a rare example of rationally constructing high‐nuclearity lanthanide clusters guided by judiciously chosen templates, is expected to stimulate more future efforts for the controllable synthesis of complex molecular or supramolecular architectures with unprecedented structural sophistication and possibly useful properties. [ABSTRACT FROM AUTHOR]

Making chains: An efficient method has been developed for the synthesis of previously unknown enantiopure difluorinated β‐amino sulfinic and sulfonic acids from (R)‐N‐tert‐butanesulfinyl imines (1) and difluoromethyl 2‐pyridyl sulfone (2). The present protocol is expected to be suitable for constructing difluorinated peptidosulfonamides of biological interest. [ABSTRACT FROM AUTHOR]