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The effects of in situ generated interfacial oxygen vacancies on the catalytic efficiency of copper–cobalt (CuCo) supported on colored TiO2 nanoparticles were studied. These catalysts were synthesized via a solid-state approach and tested for their hydrogen generation efficacy during ammonia borane (AB) hydrolysis. The formation of in situ oxygen vacancies at the metal–TiO2 interface is proposed. The in situ oxygen vacancies were studied by analyzing the rutile Raman band at 440 cm−1, and the change in the intensity of the Raman band was related to the concentration of the generated oxygen vacancies. We conclude that white TiO2 serves as a better support than reduced colored TiO2. [ABSTRACT FROM AUTHOR]

NHC-[60]fullereborane (NHC-BH2-C60H) has been synthesized, isolated in pure form, and characterized. The reaction of C60 with NHC–borane produced NHC-BH2-C60H as the first air-stable and separatable fullerene–borane compound. The formation of a N-heterocyclic carbene stabilized this borane complex of C60, and the structure of the complex was unambiguously determined throughsingle-crystal X-ray analysis. This fullerene–borane complex exhibited remarkable stability and promising electrochemical properties. [ABSTRACT FROM AUTHOR]

The objective of this study is to evaluate the effectiveness of various computational methods in reproducing the experimental heats of formation of boron hydrides using the atomization energy approach. The results have demonstrated that the empirical dispersion combined with the BJ damping function provided too large intramolecular dispersion energies, thereby compromising the accuracy of the outcomes produced by the DFT-D3 methods. Additionally, the CCSD(T) method has reproduced the experimental values only when combined with a basis set optimized for an accurate description of the core-valence correlation effect. Furthermore, the number of multicenter bonds present in the molecules under examination has also reflected their stability, as indicated by the heats of formation. Finally, a five-center two electron (5c–2e) bond has emerged in B5H9, by applying the intrinsic bond orbital (IBO) method. [ABSTRACT FROM AUTHOR]

The development of ammonium nitrate (AN)/ammonia borane (AB) as a green propellant is crucial for their applicability in different engines. This study investigates the release patterns of small products, particularly nitrogen‐containing molecules, during the initial pyrolysis of AN/AB at low and high pressures using ReaxFF MD simulations. Compared with pure AN, the addition of AB gives the hybrid system enhanced reactivity, leading to faster decomposition and higher energy release. The results show that the consumption of AN in the S13 system (AB with a mass ratio of 12.6 %) is accelerated at 1.47 MPa. NO2 and NO are produced through HNO3 and NO3. At 6.89 MPa, AN exhibits the fastest decomposition rate in the S15 system. The high pressure enhances more reactions of NO with free radicals such as NH and accelerates the release of N2. As the percentage content of AB increases to 15.3 %, more H2O while more NO2 is generated. The effect of AB on the generation of radicals such as H2 and H, is analyzed. AB not only promotes the initial pyrolysis of AN but also accelerates the conversion of intermediates. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: We reviewed works on radical borylation reactions since 2020 from two aspects. 1. Borylation from alkyl or aryl radicals: This approach involves the generation of alkyl or aryl radicals from various precursors such as halides and carboxylic acids, followed by their reaction with diboron reagents to form boron esters. 2. Borylation from boron‐centered radicals: This approach involves generating boron‐centered radicals, which then react with substrates to achieve borylation. Key Scientists: [ABSTRACT FROM AUTHOR]

Comprehensive Summary: We reviewed works on radical borylation reactions since 2020 from two aspects. 1. Borylation from alkyl or aryl radicals: This approach involves the generation of alkyl or aryl radicals from various precursors such as halides and carboxylic acids, followed by their reaction with diboron reagents to form boron esters. 2. Borylation from boron‐centered radicals: This approach involves generating boron‐centered radicals, which then react with substrates to achieve borylation. Key Scientists: [ABSTRACT FROM AUTHOR]

Studies on the synthesis of graphene oxide by the Hummers method and the synthesis of reduced graphene oxide by the chemical reduction method are gradually increasing due to the increasing use of researchers in the study of graphene oxide and reduced graphene oxide. In this study, a different approach to the synthesis of graphene oxide and reduced graphene oxide was discussed. In the study, a cyclic approach in hummers and the chemical reduction method are discussed. In the cyclic approach, it was aimed to evaluate the performance of chemicals by using sodium boron hydride at the chemical reduction stage. In the first stage, graphene oxide was synthesized from graphite using the modified hummers method. The synthesized graphene oxide was reduced by sodium boron hydride cycle. Graphene oxide synthesized by the Hummers method and reduction by sodium boron hydrate formed the first cycle for this study. This process was repeated 4 times to create a loop, taking into account the differences between the loops. The quality criteria determined for graphene oxide and reduced graphene oxide with the cyclic approach are the ratio of D peak intensity to G peak intensity (D/G), surface area measurement (YA-m²/g/), average particle size (PB-nm) and zeta, respectively. potential (ZP-mv) and atomic ratio of carbon to oxygen (C/O) were selected. The improvement rates from the quality criteria selected in the cyclical approach were - 20.69% with RGO-B2 for D/G, -10.15% with GO-B3 for C/O, 63.72% with RGO-B4 for PB, 3.93% with GO-B2 for ZP and 599.06% with GO-B3 for YA. [ABSTRACT FROM AUTHOR]

Herein, we present the preparation of a series of electronically and/or sterically distinct borenium‐type species based on a simple 2‐arylpyridine scaffold. Corresponding arylpyridine was firstly subjected to electrophilic borylation (BBr3/i‐Pr2NEt) and formed BBr2 chelate was reduced with LiAlH4 to yield arylpyridine boron dihydride. Elimination of one hydride led to Lewis acidic borenium‐like products. Four methods of hydride elimination were evaluated and influence of counterions on reactivity, Lewis acidic and luminescent properties was assessed both experimentally and computationally. Arylpyridine chelates featuring weakly coordinating counterions exhibit fluorescent properties upon UV irradiation. Several general trends were inferred to modulate emission wavelength and fluorescence quantum yield. Based on our observations, we have devised and prepared borenium‐type fluorophores with yellow‐green fluorescence and quantum yields up to 93 %. [ABSTRACT FROM AUTHOR]

The utilization of hydrogen in safety conditions is crucial for the development of a hydrogen-based economy. Among all methodologies, solid-state hydrogen release from ammonia borane through thermal stimuli is very promising due to the high theoretical hydrogen release. Generally, carbonaceous or inorganic matrices have been used to tune the reactivity of ammonia borane. Nevertheless, these solutions lack chemical tunability, and they do not allow one to properly tune the complex chemical pathway of hydrogen release from ammonia borane. In this study, we investigated the effect of a bioderived multifunctional polymeric matrix on hydrogen release from ammonia borane, reaching pure hydrogen release of 1.2 wt.% at 94 °C. We also describe new chemical pathways involving the formation of anchored intermediates, namely BxNy species. [ABSTRACT FROM AUTHOR]

Borane‐catalyzed one‐pot tandem cyclization/hydrosilylation of levulinic acid and other γ‐keto acids with hydrazines for selective access to hexahydropyridazines and tetrahydropyridazin‐3(2H)‐ones has been developed. The combination of B(C6F5)3 and Et3SiH allows for synthesis of various hexahydropyridazines and tetrahydropyridazin‐3(2H)‐ones in 67–97% yields with tolerance towards various functional groups and easy scale‐up. This reaction can be rendered enantioselective by using a chiral borane catalyst generated in situ from HB(C6F5)2 and a binaphthyl‐based chiral diene and PhMe2SiH, affording the target products in 70–92% yields with up to >99% ee. The judicious choice of borane catalyst and hydrosilane reductant proves to be critical for catalysis. Mechanistic investigations elucidate the catalytic pathway. [ABSTRACT FROM AUTHOR]

In this study, a novel method for the alkoxylation of ketones has been developed, employing sulfuric acid and N‐heterocyclic carbene boranes (NHC−boranes). The ketones are reduced using NHC−borane (diMe‐Imd‐BH3) and subsequently alkoxylate with sulfuric acid in alcohol solvents. Due to the stability of NHC−borane in the presence of both moisture and air, this reaction emerges as an effective and accessible approach for organic synthesis. [ABSTRACT FROM AUTHOR]

While azides do not react with simple alkenes except under harsh conditions, a diboron alkene analogue, the doubly cyclic alkyl(amino)carbene (CAAC)‐stabilized dicyanodiborene 1, reacts spontaneously with organic azides (7–10 equiv.) at room temperature to yield two equivalents of stable CAAC‐imino(cyano)boranes (2‐R). NMR‐spectroscopic monitoring of the reaction mixtures shows the initial formation of a 1 : 1 mixture of 2‐R and a relatively long‐lived intermediate (Int), which in the presence of excess azide is converted into a second equivalent of 2‐R. In the absence of excess azide, however, Int decomposes to 3, the product of an intramolecular C−H activation by a putative dicoordinate borylene intermediate "(CAAC)B(CN)". Mechanistic insights from trapping experiments, NMR‐spectroscopic and high‐resolution mass spectrometry data, as well as DFT computations reveal that Int is the terminal borylene end‐on‐dinitrogen adduct [(CAAC)B(CN)(η1‐N2)]. The formation of the iminoboranes 2‐R from diborene 1 and RN3 proceeds via an azide‐diborene Huisgen‐type [3+2] cycloaddition reaction, followed by a retro‐[3+2] cycloaddition, yielding 2‐R and [(CAAC)B(CN)(η1‐N2)]. The latter then undergoes either N2 extrusion and intramolecular C−H activation to generate 3, or a Staudinger‐type reaction with a second equivalent of azide to generate a second equivalent of the iminoborane 2‐R. [ABSTRACT FROM AUTHOR]

Using first-principles calculations, we explore the potentials of boron hydride (BH) for hydrogen (H 2) storage. Lithium (Li) and potassium (K) dopants enhance the H 2 storage capabilities of BH. The binding energies of Li, and K are found as −2.65 and −1.69 eV, respectively, indicating a strong binding. Ab initio molecular dynamic (AIMD) simulations at 400 K provide insights into the thermal stability of Li-, and K-doped BH. Notably, H 2 molecule adsorptions on metal-decorated BH result in substantial binding energies of −0.45 and −0.29 eV/H 2 for Li, and K, respectively. Under layered adsorption, the BH–4Li (BH–4K) accommodates up to 38H 2 (34H 2) molecules, boasting an impressive gravimetric density of 26.46 (16.57) wt.%. Even a single layer of H 2 over BH–4Li, and BH–4K corresponds to 11.70 wt% and 7.56 wt%, respectively. Adsorption mechanism of H 2 could be tuned under the influence of stress and strain. Additionally, thermodynamic analysis based on Langmuir model is employed to elucidate the H 2 storage capabilities under practical conditions of temperature and pressure. [Display omitted] • Boron Hydride Monolayer (BH-ML) has been investigated as H 2 storage materials •Selected light metals (Li, and K) were used to decorate the BH-ML •Stabilities of dopants on BH-ML were confirmed •Li, and K-doped BH-ML resulted into tremendously high H 2 storage •Thermodynamic analysis further verified the practical H 2 storage applications [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A greener and more convenient alternative to traditional methods for the generation of thiyl radical as hydrogen atom transfer (HAT) catalyst is developed, using molecular oxygen to oxidize thiol without the need for chemical initiators or light irradiation. The thiol/oxygen catalysis enables selective and efficient difunctionalization of borane. [ABSTRACT FROM AUTHOR]

This Short Review summarizes the synthesis and applications of triarylboranes (BAr3), including both homoleptic and heteroleptic species, with a focus on the modification of their electronic and structural properties via the introduction of meta -substituents with respect to the B atoms to their Ar groups. This approach constitutes a complementary alternative to conventional strategies for the design of BAr3 , which are usually based on a modification of their ortho - and/or para -substituents. An initial analysis revealed that CH3 and F are the most common meta -substituents in hitherto reported BAr3 (apart from the H atom). Thus, an extensive exploration of other substituents, e.g., heavier halogens, longer or functionalized alkyl groups, and aryl groups, will increase our knowledge of the structure and reactivity of BAr3 and eventually lead to a range of new applications. 1 Introduction 2 Scope of this Review 2.1 The Electronic and Steric Influence of meta -Substituents 2.2 Molecular Transformations Mediated by meta -Substituted Boranes 2.3 Other Examples of meta -Functionalization of BAr3 3 Conclusions and Perspectives [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A greener and more convenient alternative to traditional methods for the generation of thiyl radical as hydrogen atom transfer (HAT) catalyst is developed, using molecular oxygen to oxidize thiol without the need for chemical initiators or light irradiation. The thiol/oxygen catalysis enables selective and efficient difunctionalization of borane. [ABSTRACT FROM AUTHOR]

A stable dialkylphosphinyl radical reacted with bromoboranes to afford the corresponding phosphinoboranes accompanied with a bromophosphine under neutral condition at room temperature. The obtained phosphinoboranes have almost planar structures and have an effective P–B dative π-bond. The formation of phosphinoboranes would proceed via coordination-induced bromine abstraction from bromoboranes as a pivotal step, which was supported by the computational study. [ABSTRACT FROM AUTHOR]

The possible aromatic conjugation between 3D and 2D aromatic units is in the focus since the synthesis of benzocarborane. It has been showed that in the 3D aromatic icosahedral 1,2‐dicarba‐closo‐dodecaborane systems fused with 2D aromatic rings a global 3D/2D aromaticity does not exist. Despite this fact during the last years several studies proposed interactions between 2D and 3D moieties. Herein, while tuning the size and the effective charge of the (car)borane systems, we demonstrate that global aromatic character can be excluded in any investigated cases, and the detectable conjugative properties can be explained the effect of the well‐known negative hyperconjugation. [ABSTRACT FROM AUTHOR]

Transition‐metal‐catalyzed enantioselective transformations of aryl/aryl carbene are inherently challenging due to the difficulty in distinguishing between two arene rings in the reaction process thus remain largely less explored. The few successful examples reported so far, without exception, have all been catalyzed by Rh(II)‐complexes. Herein, we describe our successful development of a novel cationic Rh(I)/chiral diene catalytic system capable of efficient enantioselective B−H and O−H insertions with diaryl diazomethanes, allowing the access to a broad range of gem‐diarylmethine boranes and gem‐diarylmethine ethers in good yields with high enantioselectivities. Notably, previously unattainable asymmetric diarylcarbene insertion into the O−H bond was achieved for the first time. A remarkable feature of this newly designed Rh(I)/diene catalyst bearing two ortho‐amidophenyl substitutents is that it can distinguish between two arene rings of the diaryl carbene through a stereochemically selective control of π–π stacking interactions. DFT calculations indicate that the rotation‐restricted conformation of Rh(I)/diene complex played an important role in the highly enantioselective carbene transformations. This work provides an interesting and unprecedented stereocontrol mode in diaryl metal carbene transformations. [ABSTRACT FROM AUTHOR]

The small, lipophilic tetrafluoroborate anion is ubiquitous in the imidazol(in)ium and iminium precursors to N‐heterocyclic carbenes (NHCs), including cyclic (alkyl)(amino)carbenes (CAACs). Its symmetrical distribution of charge over four highly electronegative fluorine atoms confers high stability, attenuating basicity while shielding the boron center. Here we report that this inertness does not withstand the nucleophilicity of free carbenes, when combined with a polarizing lithium cation. Reaction of CAAC ⋅ HBF4 salts with LiN(SiMe3)2, a protocol widely used to liberate free CAACs, generates zwitterionic CAAC‐BF3 adducts within minutes at 80 °C, or hours at room temperature, even for bulky N‐diisopropylphenyl (DIPP) CAACs. Imidazol(in)ium tetrafluoroborates likewise form NHC‐BF3 adducts in excellent yields. [ABSTRACT FROM AUTHOR]

Herein we describe an efficient methodology for metal‐free hydroborative cleavage of lactones and esters with HBPin (Pin=pinacol) to the corresponding alcohol derivatives using ammonia borane as a pre‐catalyst. The reactions proceed under mild conditions, can be performed in a solvent‐free manner, and do not require an inert atmosphere. Combined experimental and computational mechanistic studies suggest a novel mechanism that involves μ‐aminodiboranes as catalytically active species. [ABSTRACT FROM AUTHOR]

A unique bifunctional catalyst comprised of acid site containing, hierarchical ZSM‐5 (contains acid sites) supported RuCo bimetal, was synthesized using a facile incipient wetness impregnation method. The synergistic interaction between zeolite acid sites and bimetals of this bifunctional material significantly improves its performance as a catalyst of hydrogen producing, dehydrogenation of ammonia borane. [ABSTRACT FROM AUTHOR]

We present a series of borane‐tethered cyclic (alkyl)(amino)carbene (cAAC)‐copper complexes, including a borane‐capped Cu(I) hydride. This hydride is unusually hydridic and reacts rapidly with both CO2 and 2,6‐dimethylphenol at room temperature. Its reactivity is distinct from variants without a tethered borane, and the underlying principles governing the enhanced hydricity were evaluated experimentally and theoretically. These stoichiometric results were extended to catalytic CO2 hydrogenation, and the borane‐tethered (intramolecular) system exhibits ~3‐fold enhancement relative to an intermolecular system. [ABSTRACT FROM AUTHOR]

Indolines are common motifs within pharamceuticals and natural products. Boron catalysis enables the chemoselective allylation of indoles to give allylic indolines in excellent diastereoselectivity. Mechanistic studies revealed in situ formation of the allylic borane, allylation of the imine tautomer of the indole and B–N/B–H transborylation for catalytic turnover. [ABSTRACT FROM AUTHOR]

An excellent turnover frequency of 1072 min−1 toward H 2 production from ammonia borane hydrolysis is achieved on V doping Ru/Ti 2.5 V 0.5 C 2 catalyst. The enhancive interaction between two active centers of Ru* and Ti 2.5 V 0.5 C 2 * via the doped V atoms is responsible for activation of ammonia borane and water molecules on Ru/Ti 2.5 V 0.5 C 2 catalyst, respectively. [Display omitted] • The doped V atom enhances the electron-feeding effect of support on Ru. • The dissociation energy at both active centers is reduced by the doped V atom. • The V-doped catalyst shows a turnover frequency of 1072 min−1. Designing and constructing the active center of Ru-based catalysts is the key to efficient hydrolysis of ammonia borane (NH 3 BH 3 , AB) for hydrogen production. Herein, V-doped Ru/Ti 2.5 V 0.5 C 2 dual-active center catalysts were synthesized, showing excellent catalytic ability for AB hydrolysis. The corresponding turnover frequency value was 1072 min−1 at 298 K, and the hydrolysis rate r B of AB was 235 × 103 mL·min−1·g Ru –1. X-ray photoelectron spectroscopy results indicated that the interaction between V-doped Ti 3 C 2 and catalytic metal Ru transfers electrons from Ti to Ru, resulting in electron-rich Ru species. According to density functional theory calculations, the activation energy and reaction dissociation energy of the reactants AB and H 2 O on V-doped catalysts were lower than those of Ru/Ti 3 C 2 , thus optimizing the catalytic kinetics of AB hydrolysis. The modification strategy of V-doped Ti 3 C 2 provides a new pathway for the development of high-performance catalysts for AB hydrolysis. [ABSTRACT FROM AUTHOR]

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The ubiquitous chemistry of benzene led us to explore ways to stabilise analogous borozene, by capping them with appropriate groups. The mismatch in overlap of ring‐cap fragment molecular orbitals in [(HB)2B6H6]2− is overcome by replacing the two BH caps with higher congeners of boron. We calculated the relative energies of all the polyhedral structural candidates for [(HE)2B6H6]2− (E=Al−Tl) and found hexagonal bipyramid (HBP) to be more stable with Al−H caps. A global minimum search also gives HBP as the most stable structure for [Al2B6H8]2−. The capped B6H6 ring in [(HAl)2B6H6]2− has aromaticity comparable to that of benzene. [ABSTRACT FROM AUTHOR]

Ammonia borane (AB), with high hydrogen density and stability under ambient conditions, readily releases hydrogen via catalyzed hydrolysis. However, ammonia, a byproduct of hydrogen release, limits its utilization. Citric acid, a safe and cost-effective acid catalyst, for the acid catalyst of AB hydrolysis was investigated in this study to mitigate ammonia emissions while enhancing hydrogen release. Maximal hydrogen release (3 eq.H 2) and ammonia emission suppression (<0.5 ppm) were achieved using a 2-mol/L AB aqueous solution adding into citric acid powder (molar ratio of AB: citric acid = 1:1). In contrast, the amount of hydrogen release at other concentrations and/or using the mixing method was below 2.7 mol/mol AB within several hours. Ammonia re-released even after hydrogen release in the case of high AB concentration (e.g. >4 mol/L AB aqueous solution with citric acid powder (molar ratio of AB: citric acid = 1:1)) in the solution because of formation of borate ester (1:2 borate–diol molar ratio) via mono-ammonium citrate (a borate-ester precursor), which was revealed by the solution NMR. These results reveal a cost-effective and simple on-way method for hydrogen release with suppressed impurities. Furthermore, understanding impurity generation mechanisms can contribute to utilizing AB-derived hydrogen. [Display omitted] • H 2 and NH 3 release from citric acid-catalyzed AB hydrolysis was evaluated by continuous measurement. • The theoretical maximum H 2 release and NH 3 suppression were achieved. • NH 3 release from ammonia borane was started after 5 h from the start of reaction. • The delayed NH 3 release was caused by the formation of borate ester. [ABSTRACT FROM AUTHOR]

Interface engineering is widely used to enhance the efficiency and stability of photodetectors (PDs). Although fluorine-containing materials are ideal for interface modification, they are seldom used at the NiOx/perovskite interface. This paper reports on the use of Tris(pentafluorophenyl)borane (BCF) and 2,3,5,6-tetrafluoro-7,7,8,8- tetracyanoquinodimethane (F4-TCNQ)-modified NiOx HTL to achieve high-efficiency and high-stability PDs. This study shows that BCF and F4-TCNQ interact to provide better doping ability, form Lewis adducts with Pb2+, and enhance the crystallinity of their perovskites. Interaction with nickel oxide optimizes the Ni3+/Ni2+ ratio, thus improving conductivity and charge transport capability. The F4-TCNQ:BCF modification effectively reduces interface defects, improves carrier mobility, and enhances both the performance and stability of PDs in ambient air. The detector achieves a maximum EQE value of 89.4%, a dark current density of 1.51 × 10−10A cm−2, a detectivity of 6.33 × 1013 Jones, and a LDR of 133.4 dB. Additionally, the interfacially modified device maintains over 90% of its initial performance after one month of storage in ambient air. Our results highlight the importance of F4-TCNQ:BCF interface modification and provide a reference for the further research and development of perovskite devices. [ABSTRACT FROM AUTHOR]

The formation of molecular-based functional materials is a key step towards the development of technologies at the nanoscale. Recently, it has been shown that after oxidation of closo-[B10H10]2− anions, an induced aggregation of two cluster units is achieved, retaining their parent B10 backbones as persistent building blocks. Such characterization provides an interesting scenario to further understand relevant factors leading to aggregation in a minimal structure involving two units. Here, we explore the interaction between closo-[B10H10]2− units in two isomers, namely, iso- and trans-[B20H18]2−, involving different intercluster contacts based on B–B and B–H interactions, respectively. Our results show that the inherent spherical aromatic characteristics of the parent closo-[B10H10]2− cluster are persistent in both iso- and trans-[B20H18]2− isomers as an interplay between the spherical aromatic properties from both B10 motifs, leading to an overlap of the shielding regions from shielding cone properties, ascribed as a dual spherical–spherical aromatic cluster. From 11B-NMR features, it came out that trans-[B20H18]2− involves larger differences in comparison to closo-[B10H10]2−, owing to the variation of the B10–B10 backbone provided by the intercluster B-interaction, thus resulting in a more effective aggregation connecting such building units, towards boron-based cluster materials. [ABSTRACT FROM AUTHOR]

The adducts 2M,R of general formula trans‐[(L)M{R2P(CH2)2PR2}2{N2B(C6F5)3}] (L=ø or N2, M=Mo or W, R=Et or Ph), formed from Lewis acid‐base pairing of B(C6F5)3 to a dinitrogen ligand of zero‐valent group 6 bis(phosphine) complexes trans‐[M{R2P(CH2)2PR2}2(N2)2] are shown to react with dihydrogen to afford hepta‐coordinated bis(hydride) complexes [M(H)2{R2P(CH2)2PR2}{N2B(C6F5)3}] 3M,R which feature the rare ability to activate both dinitrogen and dihydrogen at a single metal center, except in the case where M=Mo and R=Ph for which fast precipitation of insoluble [Mo(H)4(dppe)2] (dppe=1,2‐bis(diphenylphosphino)ethane) occurs. The frustrated Lewis pair (FLP)‐related reactivity of the B−N linkage in compounds 3W,R was explored and led to distal N functionalization without involvement of the hydride ligands. It is shown in one example that the resulting bis(hydride) diazenido compounds may also be obtained through a sequence involving first FLP‐type N‐functionalization followed by oxidative addition of H2. Those oily compounds were found to have limited stability in solution or in their isolated states. Finally, treatment of 3W,Et with the Lewis base N,N‐dimethylaminopyridine (DMAP) affords the simple but unknown bis(hydride)‐dinitrogen species [W(H)2(depe)2(N2)] 11Et (depe=1,2‐bis(diethylphosphino)ethane) which direct, selective formation from trans‐[W(N2)2(depe)2] is not possible. [ABSTRACT FROM AUTHOR]

The aim of this investigation was to explore the possibility to perform an asymmetric reduction, utilising a CBS‐type catalyst, of prochiral aryl methyl ketones under electrochemical conditions to generate the needed BH3 upon oxidation of NaBH4 with in situ generated I2 in the anode compartment. Therefore, various electrochemical parameters were optimised to conduct the desired formation of the chiral secondary alcohols in high to quantitative yields with a high stereochemical induction, although the catalyst loading had to be chosen relatively high to concur with the racemic reduction of the ketones by the electrogenerated BH3. [ABSTRACT FROM AUTHOR]

This work investigated in‐situ synthesis of porous silica‐nickel‐ruthenium composite catalysts for hydrolysis of ammonia borane. The precursors were prepared with an anionic surfactant, sodium dodecyl sulfate (SDS), to form porous structure in the precursor particles, and the precursors was treated in aqueous solution including sodium borohydride and ammonia borane for in‐situ process to parallelly activate and use the catalysts for hydrolysis of ammonia borane. The result of TEM and nitrogen sorption measurements suggested that the primary particle size of the in‐situ synthesized catalysts decrease with increasing the amount of SDS and sodium chloride as the additive for controlling the primary particle size probably because of the effect of sodium ions to inhibit nuclei growth of the primary particles. From the EDS analyses, the composition of active nickel and ruthenium contents increased with increasing the amount of SDS and sodium chloride except for the highest amount of SDS probably because of adsorption of the metal cations with the excess amount of the surfactant anion to decrease the amount of the metal cations including the catalyst. The in‐situ synthesized catalyst including small size primary particles and high nickel and ruthenium content tended to exhibit high activity for hydrolysis of ammonia borane. [ABSTRACT FROM AUTHOR]

Molecules with chiral boron atoms have been scarcely studied due to limited synthetic access. Herein, we report a new method for their synthesis via asymmetric insertion of arydiazoacetates into the B–H bonds of prochiral carbene–boranes NHC–BH2R. The reaction is catalyzed by the rhodium(I) complex with the chiral diene ligand tBu2-TFB, which can be conveniently prepared by diastereoselective coordination of the racemic diene with (S-Salox)Rh(CO)2. The target boranes were typically obtained in 75–90% yields with 90–95% ee. [ABSTRACT FROM AUTHOR]

The limited analgesic efficiency of magnesium restricts its application in pain management. Here, we report boron hydride (BH) with ion currents rectification activity that can enhance the analgesic efficiency of magnesium without the risks of drug tolerance or addiction. We synthesize MgB2, comprising hexagonal boron sheets alternating with Mg2+. In pathological environment, Mg2+ is exchanged by H+, forming two‐dimensional borophene‐analogue BH sheets. BH interacts with the charged cations via cation‐pi interaction, leading to dynamic modulation of sodium and potassium ion currents around neurons. Additionally, released Mg2+ competes Ca2+ to inhibit its influx and neuronal excitation. In vitro cultured dorsal root neurons show a remarkable increase in threshold potential from the normal −35.9 mV to −5.9 mV after the addition of MgB2, indicating potent analgesic effect. In three typical pain models, including CFA‐induced inflammatory pain, CINP‐ or CCI‐induced neuropathic pain, MgB2 exhibits analgesic efficiency approximately 2.23, 3.20, and 2.0 times higher than clinical MgSO4, respectively, and even about 1.04, 1.66, and 1.95 times higher than morphine, respectively. The development of magnesium based intermetallic compounds holds promise in addressing the non‐opioid medical need for pain relief. [ABSTRACT FROM AUTHOR]

Hydrolysis of ammonia borane (NH3BH3, AB) involves multiple undefined steps and complex adsorption and activation, so single or dual sites are not enough to rapidly achieve the multi‐step catalytic processes. Designing multi‐site catalysts is necessary to enhance the catalytic performance of AB hydrolysis reactions but revealing the matching reaction mechanisms of AB hydrolysis is a great challenge. In this work, we propose to construct RuPt−Ti multi‐site catalysts to clarify the multi‐site tandem activation mechanism of AB hydrolysis. Experimental and theoretical studies reveal that the multi‐site tandem mode can respectively promote the activation of NH3BH3 and H2O molecules on the Ru and Pt sites as well as facilitate the fast transfer of *H and the desorption of H2 on Ti sites at the same time. RuPt−Ti multi‐site catalysts exhibit the highest turnover frequency (TOF) of 1293 min−1 for AB hydrolysis reaction, outperforming the single‐site Ru, dual‐site RuPt and Ru−Ti catalysts. This study proposes a multi‐site tandem concept for accelerating the dehydrogenation of hydrogen storage material, aiming to contribute to the development of cleaner, low‐carbon, and high‐performance hydrogen production systems. [ABSTRACT FROM AUTHOR]

Xanthene‐backbone FLPs featuring secondary borane functions −B(ArX)H (where ArX=C6F5 (ArF) or C6Cl5 (ArCl)) have been targeted through reactions of the dihydroboranes Me2S ⋅ BArXH2 with [4,5‐xanth(PR2)Li]2 (R=Ph, iPr), and investigated in the synthesis of related cationic systems via hydride abstraction. The reactivity of these systems (both cationic and charge neutral) with ammonia have been probed, with a view to probing the potential for proton shuttling via N−H bond 'activation.' We find that in the case of four‐coordinate boron systems (cationic or change neutral), the N−H linkage remains intact, supported by a NH⋅⋅⋅P hydrogen bond which is worth up to 17 kcal mol−1 thermodynamically, and enabled by planarization of the flexible xanthene scaffold. For cationic three coordinate systems, N‐to‐P proton transfer is viable, driven by the ability of the boron centre to stabilise the [NH2]− conjugate base through N‐to‐B π bonding. This proton transfer can be shown to be reversible in the presence of excess ammonia, depending on the nature of the B‐bound ArX group. It is viable in the case of C6F5 substituents, but is prevented by the more sterically encumbering and secondary donor‐stabilising capabilities of the C6Cl5 substituent. [ABSTRACT FROM AUTHOR]

Despite the paramount importance of the Suzuki–Miyaura coupling (SMC) in academia and industry, and the great promise of iron to offer sustainable catalysis, iron‐catalyzed SMC involving sp3‐hybridized partners is still in its infancy. We herein report the development of a versatile, well‐defined electron‐deficient anilido‐aldimine iron(II) catalyst. This catalyst effectively performed C(sp3)−C(sp2) and C(sp3)−C(sp3) SMC of alkyl halide electrophiles and (hetero)aryl boronic ester and alkyl borane nucleophiles respectively, in the presence of a lithium amide base. These couplings operated under mild reaction conditions and displayed wide functional group compatibility including various medicinally relevant N‐, O‐ and S‐based heterocycles. They also tolerated primary, secondary and tertiary alkyl halides (Br, Cl, I), electron‐neutral, ‐rich and ‐poor boronic esters and primary and secondary alkyl boranes. Our methodology could be directly and efficiently applied to synthesize key intermediates relevant to pharmaceuticals and a potential drug candidate. For C(sp3)−C(sp2) couplings, radical probe experiments militated in favor of a carbon‐centered radical derived from the electrophile. At the same time, reactions run with a pre‐formed activated boron nucleophile coupled to competition experiments supported the involvement of neutral, rather than an anionic, (hetero)aryl boronic ester in the key transmetalation step. [ABSTRACT FROM AUTHOR]

The synthesis of the phosphorus‐capped heptaphenylsilsesquioxane T7Ph7P is reported. We show that, unlike previous examples, it readily forms Lewis acid‐base adducts with boranes of different steric demand and the FeCO4 fragment. All complexes were characterized by multinuclear NMR and IR spectroscopy in solution and the solid state. The molecular structures of the adducts with BPh3 and B(C6F5)3 were determined from XRD suitable single crystals. The relative conformation of the Ph and C6F5 rings in T7Ph7P−B(C6F5)3 suggests favorable π‐interactions, stabilizing the adducts to such a degree that attempts to activate H2 or CO2 were unsuccessful. [ABSTRACT FROM AUTHOR]

This study focuses on the synthesis of H‐ and MeO‐ functionalized alkali metal hypersilyl borates. Consequently, two distinct silanides were used as polysilane frameworks for our chemical manipulations. Tris(silyl)silanide (1) and tris(trimethoxysilyl)silanide (2) react in the same manner with the BH3 ⋅ SMe2 complex to obtain two new alkali metal hypersilyl borates [(R3Si)3SiBH3M (M=alkali metal; R=H, (3), R=MeO, (4 a–c))] in good to excellent yields. NMR spectroscopy for all compounds and single‐crystal X‐ray crystallography for 3 and 4 a, b enabled a clear structural characterization. Single crystal X‐ray analysis of 3 showed a dimeric structure, where two THF‐molecules and three hydrides from the BH3‐group contribute to the coordination sphere of the lithium atom. Interestingly, crystals suitable for X‐ray analysis of 4 a and 4 b showed a solvent‐free cluster formation, due to the coordination of the MeO groups. Both species form coordination polymers with different coordination modes depending on the nature of the alkali metal. Attempted hydride abstraction reactions of 3 and 4 with various reagents under the formation of the free boranes proceeded unselectively. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Herein, we present a method for the homogeneous hydrogenation of nitroarenes to produce anilines using low catalyst loading (1 mo%) of copper N‐heterocyclic carbene complexes as the catalyst and ammonia borane as the source of hydrogen. A wide range of nitroarenes, featuring diverse functional groups, were selectively transformed into their corresponding primary aromatic amines with high yields. This process can be readily scaled up and exhibits compatibility with various sensitive functional groups, including halogen, trifluoromethyl, aminomethyl, alkenyl, cyano, ester, amide, and hydroxyl. Notably, this catalytic methodology finds application in the synthesis of essential drug compounds. Mechanistic investigations suggest that the in‐situ‐generated Cu‐H species may serve as active intermediates, with reduction pathways involving species such as azobenzene, 1,2‐diphenylhydrazine, nitrosobenzene, and N‐phenylhydroxylamine. [ABSTRACT FROM AUTHOR]

B(C6F5)3 and the corresponding anion [B(C6F5)4]− are ubiquitous in main group and transition metal chemistry. Known derivatives are generally limited to the incorporation of electron donating substituents. Herein we describe electrophilic fluorination and dearomatization of such species using XeF2 in the presence of BF3 or Lewis acidic cations. In this fashion the anions [HB(C6F5)3]−, [B(C6F5)4]− and [(C6F5)3BC≡NB(C6F5)3]−, are converted to [FB(C6F7)3]−, [B(C6F7)4]−, and [(C6F7)3BC≡NB(C6F7)3]−, respectively. Similarly, the borane adducts (L)B(C6F7)3 (L=MeCN, OPEt3) are produced. These rare examples of electrophilic attack of electron deficient rings proceed as [XeF][BF4] acts as a frustrated Lewis pair effecting fluorination and dearomatization of C6F5 rings. [ABSTRACT FROM AUTHOR]

Borane catalysis has emerged as a powerful technology in epoxide polymerization. Still, the structure‐activity correlations for these catalysts are not fully understood to date, especially regarding compounds with nonionic backbones. Thus, in this work, 13 different borane catalysts of this respective type are described and investigated for their epoxide oligomerization and polymerization performance, using propylene oxide (PO), 1‐butylene oxide (BO) and allyl glycidyl ether (AGE) as monomers. Structurally, special emphasis is put on catalysts with different linker lengths and linker flexibilities as well as the introduction of more than two borane functionalities. Importantly, this screening is conducted both under typical polymerization conditions as well as under the chain transfer agent (CTA)‐rich conditions relevant for large‐scale production. It is found that suitable preorganization of the borane groups, such as present in biphenyl derivatives, offers a simple route to high‐performing catalysts and quantitative monomer conversion of the investigated epoxides. Furthermore, it is demonstrated that a diborane‐catalyzed oligomerization can be kept active over weeks, whereby repeated addition of monomer batches (14 steps) constantly results in full conversion and well‐defined oligoethers, underlining the practical potential of this method. The absence of co‐initiating counter ions is suggested as an inherent advantage of nonionic catalysts. [ABSTRACT FROM AUTHOR]

This paper introduces a confinement approach to enhance solid-state hydrogen storage by designing a nano-tubular and nano-fibrous structured boron-based storage medium. We detail the preparation of the confinement matrix, emphasizing its nanotubular and microfibrous structures provided by activated halloysite and sepiolite clays to achieve suitable confinement for ammonia borane (NH 3 BH 3 , AB). The thermolysis characteristics are thoroughly investigated in a lab-scale hydrogen reactor, elucidating the activation effects (thermal, acid, and both thermal-acid) on confinement and hydrogen generation performance. The resulting composite exhibits improved thermal stability and controlled hydrogen desorption characteristics, offering great promise for safe and efficient hydrogen storage applications. This research underscores the potential of tailored nanomaterials in advancing hydrogen storage technologies, with significant implications for clean energy solutions and the sustainable transportation sector. AB confined in acid-activated nano-tubular clay has shown improved hydrogen generation features at 120 °C, resulting in the highest improvement in H 2 equivalent per AB mole (98 %) and the initial hydrogen generation rate (233 %) while minimizing induction time up to 90 %. [Display omitted] • Tubular and fiber structured clays were used as ammonia borane scaffolds medium. • Halloysite and sepiolite clays were activated by thermal, acidic and combined method. • NH 3 BH 3 based nanocarriers were prepared via modified infiltration-confinement method. • Hydrogen production performance of composites were tested at 120 °C. • Acid activated composites showed the highest performance. [ABSTRACT FROM AUTHOR]

Reactivity of (triphosphine)MoIV‐nitrido complex generated by N2 splitting, toward boranes is reported. The simple adduct Mo≡N→BH3 is observed with BH3.SMe2 while 1,2 addition is evidenced with 9‐BBN leading to H−Mo=NBR2. A second addition of BH3.SMe2 is facile and forms an unprecedented complex featuring two bridging H between two B and the Mo centers. Addition of PMe3 or BH3.SMe2 promotes reductive elimination and N−H bond formation. The full sequence of functionalization at Mo≡N obtained after N2 splitting is therefore evidenced in this work. [ABSTRACT FROM AUTHOR]

The formylation of N-methylaniline (1a) with CO2 and ammonia borane, NH3·BH3 (AB) produced selectively N-methyl-N-phenylformamide (3a) in the presence of the halide imidazolium salts ([IL]X). In contrast, a mixture of two products, formylated 3a and methylated 2a (N,N-dimethylaniline), was obtained in the presence of non-halide imidazolium salts, containing BF4−, PF6− or OS (octyl sulfate) anions. Reactions of other primary and secondary amines with AB and CO2 carried out in the presence of halide salt, [dbim]Cl (dbim = 1,3-dibutyl imidazolium cation) selectively lead to the formation of formamides as the only products. The effect of ionic liquids on the selectivity of amine formylation was explained by their ability to stabilize different forms of boron formates. In the presence of halide salts, the reaction of AB with CO2 results in the formation of BH(OCHO)2 which is responsible for the formylation of amines to formamides. In contrast, the formation of a mixture of boron formates, BHn(OCHO)3−n (n = 1, 2), in the presence of non-halogenated imidazolium salts results in the production of a mixture of formylated and methylated amine derivatives. [ABSTRACT FROM AUTHOR]

The review reports on investigations and studies that have contributed in the last 20 years (2003–2023) to the clarification of the mechanisms governing the chemical vapor generation (CVG) of hydrides and other volatile metallic species using aqueous phase derivatization with tetrahydridoborate (1-)(THB) and amine boranes, which is widely used in determination and speciation analysis of trace elements by atomic optical and mass spectrometry. The discussion begins with the early investigations leading to definition of the mechanism of hydrolysis of aqueous THB and that of reaction conditions. The new knowledge represents important achievements for the clarification of controversial aspects that plagued CVG for more than 35 years and stimulated further studies which are discussed in detail. They concern with the mechanism of hydrolysis of amine boranes, the mechanism of interferences, the role played by chemical additives and the definition of more general reaction models for CVG, which are valid for both analytical and non-analytical reaction conditions. The latest developments and the analytical applications of the new knowledge to trace element analysis are discussed. [ABSTRACT FROM AUTHOR]

The restructuring reactions of three siloxane copolymers: poly(Me2SiO-co-HMeSiO), poly(PhMeSiO-co-HMeSiO) and poly(3,3,3-F3PrMeSiO-co-HMeSiO) in the presence of B(C6F5)3 (TPFPB) were investigated. The studied restructuring reactions are the result of the hydride transfer process between two silicon atoms, which is mediated by TPFPB. B(C6F5)3. Initially, the restructuring process produces high molecular weight, branched siloxane copolymers. These copolymers are soluble and capable of forming thin layers. Continuing this reaction leads to cross-linking of the siloxane polymer and the formation of an insoluble gel. The same restructuring process allows the resulting films to be converted into hard coatings after solvent evaporation. The restructuring process of siloxane copolymers was compared with the previously studied restructuring of polyhydromethylsiloxane homopolymer. Although the mechanism of branching and cross-linking is similar, diorganosiloxane units play an important role in the restructuring process as well as influence the properties of the obtained coatings. [ABSTRACT FROM AUTHOR]

Starting from two different cyano‐functionalized organoboranes, we demonstrate that 1,3‐dipolar [3+2] azide‐nitrile cycloaddition can serve to generate libraries of alkyl‐tetrazole‐functionalized compounds capable of intramolecular N→B‐Lewis adduct formation. Due to the relatively low basicity of tetrazoles, structures can be generated that exhibit weak and labile N→B‐coordination. The reaction furnishes 1‐ and 2‐alkylated regio‐isomers that exhibit different effective Lewis‐acidities at the boron centers, and vary in their optical absorption and fluorescence properties. Indeed, we identified derivatives capable of selectively binding cyanide over fluoride, as confirmed by 11B NMR. This finding demonstrates the potentialities of this synthetic strategy to systematically fine‐tune the properties of lead structures that are of interest as chemical sensors. [ABSTRACT FROM AUTHOR]