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Metal‐Organic frameworks (MOFs) have the advantages of high porosity, angstrom‐scale pore size, and unique structure. In this work, a kind of MOFs, UiO‐66 and its derivatives (including aminated UiO‐66‐(NH2)2 and sulfonated UiO‐66‐(NH‐SAG)2), were constructed on the inner surface of solid‐state nanopores for ultra‐selective proton transport. UiO‐66 and UiO‐66‐(NH2)2 nanocrystal particles were in‐situ grown at the orifice of glass nanopores firstly, which were used to investigate the ionic current responses in LiCl and HCl solutions when the monovalent anions (Cl−) were unchanged. Compared with UiO‐66‐modifed nanopores, the aminated MOFs modification (UiO‐66‐(NH2)2) can improve the proton selectivity obviously. However, when the UiO‐66‐(NH‐SAG)2 nanopore is prepared by further post‐modification with sulfo‐acetic acid, lithium ions can hardly pass through the channel, and the interaction between protons and sulfonic acid groups can promote the transport of protons, thus achieving ultra‐high selectivity to protons. This work provides a new way to achieve sub‐nanochannels with high selectivity, which can widely be used in ion separation, sensing and energy conversion. [ABSTRACT FROM AUTHOR]

The reactivity of diazadiphosphapentalene 1 towards various substrates was investigated. Reaction of 1 with ammonia-borane resulted in transfer hydrogenolysis concomitantly with the cleavage of a P-N bond. By treatment of 1 with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), oxidation took place at one of the phosphorus atoms of 1, and a PV/PIII mixed-valence derivative was isolated. At the same time, it was demonstrated that only one of the phosphorus atoms in 1 behaves as an electron donor for electrophiles and Lewis acids. The former afforded an intramolecularly coordinated phosphine-phosphenium species, whereas the latter demonstrates the ligand property of 1. UV irradiation induced rearrangement of 1 into another example of another diazadiphosphapentalene. [ABSTRACT FROM AUTHOR]

Solid‐state glass nanopipettes provide a promising confined space that offers several advantages such as controllable size, simple preparation, low cost, good mechanical stability, and good thermal stability. These advantages make them an ideal choice for various applications such as biosensors, DNA sequencing, and drug delivery. In this review, we first delve into the functionalized nanopipettes for sensing various analytes and the methods used to develop detection means with them. Next, we provide an in‐depth overview of the advanced functionalization methodologies of nanopipettes based on diversified chemical kinetics. After that, we present the latest state‐of‐the‐art achievements and potential applications in detecting a wide range of targets, including ions, molecules, biological macromolecules, and single cells. We examine the various challenges that arise when working with these targets, as well as the innovative solutions developed to overcome them. The final section offers an in‐depth overview of the current development status, newest trends, and application prospects of sensors. Overall, this review provides a comprehensive and detailed analysis of the current state‐of‐the‐art functionalized nanopipette perception sensing and development of detection means and offers valuable insights into the prospects for this exciting field. [ABSTRACT FROM AUTHOR]

Oxidative addition of the C−O bond in L2PhB: (L=oxazol-2-ylidene) to an AlI center induced ring expansion of an oxazol-2-ylidene ring, affording a unique organoboron species formally involving either an Al, N, O mixed heterocyclic carbene or anionic (amino)(boryl)carbene fragment. [ABSTRACT FROM AUTHOR]

The palladacycle-catalyzed asymmetric PH addition of 4- oxo-enamides has been developed, which provides efficient access to phosphinocarboxamides and their analogues. Solvent-mediated reversal of stereoselectivity ( ee from +96 % to −92 %) was observed, and the underlying mechanism that allows facile access to both enantiomers of the product by judicious choice of solvents is revealed. [ABSTRACT FROM AUTHOR]

The syntheses of a zwitterionic base-stabilized digermadistannacyclobutadiene and tetragermacyclobutadiene supported by amidinates and low-valent germanium amidinate substituents are described. The reaction of the amidinate GeI dimer, [LGe:]2 ( 1, L=PhC(N tBu)2), with two equivalents of the amidinate tin(II) chloride, [LSnCl] ( 2), and KC8 in tetrahydrofuran (THF) at room temperature afforded a mixture of the zwitterionic base-stabilized digermadistannacyclobutadiene, [L2Ge2Sn2L′2] ( 3; L′=LGe:), and the bis(amidinate) tin(II) compound, [L2Sn:] ( 4). Compound 3 can also be prepared by the reaction of 1 with [LArSnCl] ( 5, LAr= tBuC(NAr)2, Ar=2,6- iPr2C6H3) in THF at room temperature. Moreover, the reaction of 1 with the 'onio-substituent transfer' reagent [4-NMe2-C5H4NSiMe3]OTf ( 8) in THF and 4-( N, N-dimethylamino)pyridine (DMAP) at room temperature afforded a mixture of the zwitterionic base-stabilized tetragermacyclobutadiene, [L4Ge6] ( 9), the amidinium triflate, [PhC(NH tBu)2]OTf ( 10), and Me3SiSiMe3 ( 11). X-ray structural data and theoretical studies show conclusively that compounds 3 and 9 have a planar and rhombic charge-separated structure. They are also nonaromatic. [ABSTRACT FROM AUTHOR]

The synthesis and reactivity of a silyliumylidene cation stabilized by an amidinate ligand and 4-dimethylaminopyridine (DMAP) are described. The reaction of the amidinate silicon(I) dimer [ LSi:]2 ( 1; L=PhC(N tBu)2) with one equivalent of N-trimethylsilyl-4-dimethylaminopyridinium triflate [4-NMe2C5H4NSiMe3]OTf and two equivalents of DMAP in THF afforded [ LSi(DMAP)]OTf ( 2). The ambiphilic character of 2 is demonstrated from its reactivity. Treatment of 2 with 1 in THF afforded the disilylenylsilylium triflate [ L′2( L)Si]OTf ( 3; L′= LSi:) with the displacement of DMAP. The reaction of 2 with [K{HB( iBu)3}] and elemental sulfur in THF afforded the silylsilylene [ LSiSi(H){(N tBu)2C(H)Ph}] ( 4) and the base-stabilized silanethionium triflate [ LSi(S)DMAP]OTf ( 5), respectively. Compounds 2, 3, and 5 have been characterized by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Polymorphism control of metal‐organic frameworks is highly desired for elucidating structure‐property relationships, but remains an empirical process and is usually done in a trial‐and‐error approach. We adopted the rarely used actinide cation Th4+ and a ditopic linker to construct a series of thorium‐organic frameworks (TOFs) with a range of polymorphs. The extraordinary coordination versatility of Th4+ cations and clusters, coupled with synthetic modulation, gives five distinct phases, wherein the highest degree of interpenetration (threefold) and porosity (75.9 %) of TOFs have been achieved. Notably, the O atom on the capping site of the nine‐coordinated Th4+ cation can function as a bridging unit to interconnect neighboring secondary building units (SBUs), affording topologies that are undocumented for other tetravalent‐metal‐containing MOFs. Furthermore, for the first time HCOOH has been demonstrated as a bridging unit of SBUs to further induce structural complexity. The resulting TOFs exhibit considerably different adsorption behaviors toward organic dyes, thus suggesting that TOFs represent an exceptional and promising platform for structure‐property relationship study. [ABSTRACT FROM AUTHOR]

Effective capture of radioactive iodine is of paramount importance for the safe and long‐term storage of fission products in the nuclear fuel cycle. Herein, a series of functionalized Th‐UiO‐66 MOFs was employed as a model to investigate the effects of substituents on iodine adsorption in both solution and vapor states. Sorption studies revealed that the electro‐donating amino group exhibits the most positive role on increasing the removal rate of iodine from cyclohexane and the uptake capacity of iodine vapor. Particularly, the disubstituted Th‐UiO‐66‐(NH2)2 can effectively remove 91.9 % of iodine (300 mg L−1) from cyclohexane and capture 969 mg g−1 iodine vapor, significantly higher than 59.6 % and 334 mg g−1 of untagged Th‐UiO‐66, respectively. In addition, the substituent effect on the radiolytic stability of MOFs was for the first time investigated, leading to the unearthing of one of the most radioresistant MOFs Th‐UiO‐66‐NH2 reported to date. [ABSTRACT FROM AUTHOR]

Silver nanowires (AgNWs) have been extensively studied as promising nanomaterials in optics, next‐generation flexible electronics, and energy‐related fields, but the stability and the properties at single‐nanowire level still need to be investigated carefully. We have successfully prepared single palladium@silver nanowire electrodes (Pd@AgNWEs) by using a laser‐assisted pulling method, followed by a galvanic replacement reaction (GRR). The results show that the chemical stability of AgNWs can be improved greatly by coating a small amount of Pd, and the Pd@AgNWEs exhibit superior electrocatalytic performance in methanol oxidation. This work can give us a new insight to investigate the performance of devices/catalysts at the single‐particle/nanowire level that will benefit research in flexible electronics and energy‐related fields. [ABSTRACT FROM AUTHOR]

Synthetic challenges have significantly slowed the development of the catalytic asymmetric hydroarsination reaction despite it being a highly attractive C−As bond formation methodology. In addition, there is a poor understanding of the main reaction steps in such reactions which limit further development in the field. Herein, key intermediates of the hydroarsination reaction catalyzed by a PCP NiII‐Cl pincer complex are presented upon investigating the reaction with DFT calculations, conductivity measurements, NMR spectroscopy, and catalytic screening. The novel Ni–Cl–As interaction proposed was then contrasted against known NiII‐catalyzed hydrophosphination reactions to highlight dissimilarities between them even though P and As share a close group relationship. Lastly, the asymmetric hydroarsination of nitroolefins was further developed to furnish a library of chiral organoarsines in up to 99 % yield and 80 % ee under mild conditions (−20 °C to RT) between 5 to 210 mins. [ABSTRACT FROM AUTHOR]

This communication reports novel luminescent rhenium(I)–polypyridine complexes appended with a perylene diimide (PDI) or benzoperylene monoimide (BPMI) moiety through a non‐conjugated linker. The photophysical and photochemical properties originating from the interactions of the metal polypyridine and perylene units were exploited to afford new cellular reagents with thiol‐sensing capability and excellent photocytotoxic activity. [ABSTRACT FROM AUTHOR]

Understanding the electrocatalytic activity at single nanoparticles/nanoclusters level is extremely important. In this work, a method for the electro‐deposition of single Pt–Pd nanoparticles (NPs) is described using a single nanopore electrode as a template. The electro‐deposition process was investigated carefully and the results show that the process is controlled by diffusion and electro‐crystallization process, simultaneously, and the glass sheath property around the nanopore has a large impact on the formation of single Pt–Pd NPs due to the "edge effect". The prepared single Pt–Pd NPs exhibit excellent electrocatalytic activity in the methanol oxidation reaction, which can be used to screen electrocatalysts with high efficiency for utility in the energy field. Living on the edge: Single Pt–Pd nanoparticle (NPs) electrode was fabricated by an electro‐deposition method using a single nanopore electrode as a template, which was controlled by the "edge effect." The prepared single Pt–Pd NPs exhibit excellent electrocatalytic activity towards methanol oxidation reaction, which can be used to screen electrocatalysts with high efficiency for utility in the energy field. [ABSTRACT FROM AUTHOR]

Mechanochemistry is emerging as a powerful solvent-free approach to chemical synthesis, having been applied to metal oxides, pharmaceutical materials, organic compounds and to a lesser extent, coordination complex synthesis. Notably, examples of applications of mechanochemical methodologies in the synthesis of main-group compounds are few and far between. Herein, we demonstrate that ball milling enabled the solvent-free synthesis of a range of phosphazane frameworks with a broad substrate scope, yielding seven new acyclic and macrocyclic species. The strength of this methodology is highlighted by a fast, selective and high-conversion product generation from poorly soluble starting materials, thereby demonstrating mechanochemistry as a real alternative to solution-based methods in synthetic main-group chemistry. [ABSTRACT FROM AUTHOR]

The first asymmetric phospha-Michael addition of diarylphosphines to N-enoyl phthalimides has been developed in the presence of a chiral palladacycle catalyst. A library of free chiral tertiary phosphine adducts were directly obtained with excellent yields and enantioselectivities. Products can be subsequently functionalized to afford β-phosphinoamides, the direct preparation of which from cinnamides has been notoriously challenging. [ABSTRACT FROM AUTHOR]

Keywords: metal coordination; metal-organic frameworks; modulator; polymorphism; thorium EN metal coordination metal-organic frameworks modulator polymorphism thorium 17504 17504 1 12/22/21 20211215 NES 211215 B The extraordinary coordination versatility b of the Th SP 4+ sp cation and the unexpected bridging role of formate allows polymorphism control of thorium-organic frameworks (TOFs) with five distinct phases, wherein the highest degree of porosity and interpenetration for TOFs have been achieved. Front Cover: Unveiling the Unique Roles of Metal Coordination and Modulator in the Polymorphism Control of Metal-Organic Frameworks (Chem. Eur. J. 70/2021) Metal coordination, metal-organic frameworks, modulator, polymorphism, thorium. [Extracted from the article]

Palladium and platinum complexes containing a sulfur-functionalised N-heterocyclic carbene (S-NHC) chelate ligand have been synthesised. The absolute conformations of these novel organometallic S-NHC chelates were determined by X-ray structural analyses and solution-phase 2D 1H-1H ROESY NMR spectroscopy. The structural studies revealed that the phenyl substituents on the stereogenic carbon atoms invariably take up the axial positions on the Pd-C-S coordination plane to afford a skewed five-membered ring structure. All of the chiral complexes are structurally rigid and stereochemically locked in a chiral ring conformation that is either ( Rs, S, R)-λ or ( Ss, R, R)-δ in both the solid state and solution. [ABSTRACT FROM AUTHOR]

In intermolecular Heck reactions of styrene and vinylarenes, the aryl and vinyl groups routinely insert at the β position. However, selective insertion at the α position has been very rare. Herein, we provide a missing piece in the palette of Heck reaction, which gave >20:1 α selectivity. The key to our success is a new ferrocene 1,1′-bisphosphane (dnpf) that carries 1-naphthyl groups. Our mechanistic studies revealed that the high α selectivity is partly attributable to the steric effect of dnpf. The rigid and bulky 1-naphthyl groups of dnpf sterically disfavor β insertion. [ABSTRACT FROM AUTHOR]

Cover Feature: Boosting the Iodine Adsorption and Radioresistance of Th-UiO-66 MOFs via Aromatic Substitution (Chem. Eur. J. 4/2021) Keywords: iodine; metal-organic frameworks; radioresistance; substituent effects; thorium EN iodine metal-organic frameworks radioresistance substituent effects thorium 1162 1162 1 01/20/21 20210118 NES 210118 B Effective capture of radioactive iodine b is of paramount importance for the safe and long-term storage of fission products in the nuclear fuel cycle. Iodine, metal-organic frameworks, radioresistance, substituent effects, thorium. [Extracted from the article]

Mechanochemistry is emerging as a powerful solvent ‐ free approach to chemical synthesis. Examples of mechanochemical methodologies in the synthesis of main ‐ group compounds are few and far between. It is shown that ball ‐ milling enables the solvent ‐ free synthesis of a range of phosphazane frameworks with a broad substrate scope, yielding new acyclic and macrocyclic species. Fast, selective and high ‐ yielding product generation from poorly soluble starting materials demonstrates the potential of mechanochemistry as a powerful alternative to solution ‐ based methods in synthetic main ‐ group chemistry. More information can be found in the Full Paper by F. García et al. on page 11279. [ABSTRACT FROM AUTHOR]