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Difluoroboryl complexes obtained from N-acyl hydrazones upon brief treatment with boron trifluoride and allylic silane serve as efficient acceptors of alkyl radicals. The reaction of the boryl chelates with carboxylic acids in the presence of an acridine-type photocatalyst leading to N-acyl hydrazides is described. The efficiency of addition at the C═N bond of the chelates is determined by the formation of a nitrogen-centered radical stabilized by the boron-containing heterocyclic ring.

Different types of high‐yield, easily scalable syntheses for cyano(fluoro)borates Kt[BFn(CN)4−n] (n=0–2) (Kt=cation), which are versatile building blocks for materials applications and chemical synthesis, have been developed. Tetrafluoroborates react with trimethylsilyl cyanide in the presence of metal‐free Brønsted or Lewis acid catalysts under unprecedentedly mild conditions to give tricyanofluoroborates or tetracyanoborates. Analogously, pentafluoroethyltrifluoroborates are converted into pentafluoroethyltricyanoborates. Boron trifluoride etherate, alkali metal salts, and trimethylsilyl cyanide selectively yield dicyanodifluoroborates or tricyanofluoroborates. Fluorination of cyanohydridoborates is the third reaction type that includes direct fluorination with, for example, elemental fluorine, stepwise halogenation/fluorination reactions, and electrochemical fluorination (ECF) according to the Simons process. In addition, fluorination of [BH(CN)2{OC(O)Et}]− to result in [BF(CN)2{OC(O)Et}]− is described., Three different convenient synthetic routes towards cyano(fluoro)borates, which are versatile building blocks, especially for room temperature ionic liquids, have been developed using easily accessible starting materials.

Boron dipyrrins (Bodipy) are unique complexes occupying an intermediate position between classical coordination and organometallic compounds. The enormous interest of researchers from all over the world to the compounds of this class has by now provided an endless stream of publications that requires generalization. Existing reviews and original publications do not fully cover the structural diversity of Bodipy and their possible applications in engineering, medicine, analytical chemistry, optics, photonics, etc. In this paper, w e present the results, mainly of our own research, which for the first time allowed us to establish the physicochemical principles of the formation of Bodipy (the reasons for the low rates of complexation of ligands with boron trifluoride), changes in the spectral and photophysical properties of alkylated Bodipy complexes with the separation of contributions from universal and specific solvation, and examples of functionalization of inorganic and organic polymer materials based on Bodipy of different structures. Examples of the current team’s Bodipy research in different practical areas are presented.

The cyclization of a series of nonheterocyclic allenyl aryl ketones was examined using boron trifluoride etherate and indium triflate to mediate the reaction. Yields with BF3 were low in most instances due mainly to competitive destruction of the substrates. With In(OTf)3, there was less decomposition, and the yields of the cyclized product were much higher, but only for substrates with electron-donating substituents. Cyclization did not occur without those substituents. A computational study using the ωB97X-D/6-311+G(2d,p)//ωB97X-D/6-31+G(d,p) method confirmed better stability of the σ-complexed substrate by indium(III) and that meta-substituents on the phenyl ring of the substrate significantly influenced the activation barrier of the cyclization, whereas the effect of para-substituents was almost negligible. The computational results supported the idea that the cyclization is a 4π-electrocyclization and not a 5-endo-dig ring closure as had been proposed in the literature.

The boron–transition-metal triple-bond complexes FB≡MF2 (M= Ir, Os, Re, W, Ta) were trapped in excess solid neon and argon through metal atom reactions with boron trifluoride and identified by matrix isolation infrared spectroscopy and quantum chemical calculations. The FB≡MF2 molecule features very high 11B–F stretching frequencies at 1586.6 cm–1 (Ir), 1526.6 cm–1 (Os), 1505.5 cm–1 (Re), and 1453.2 cm–1 (W), respectively. The very high strength of B≡M bonds with triple-bonding character is confirmed by EDA-NOCV calculations and the active molecular orbital and NBO analysis. The experimental observation of FB stabilization by heavy transition-metal atoms with triple bonds opens the door to design new boron–transition-metal complexes.

A previously unknown carbofunctional (trimethoxysilyl)propyl derivative of the 2-mercaptobenzoxazole, C6H4NOCS(CH2)3Si(OMe)3, containing a tetracoordinated silicon atom was synthesized by nucleophilic substitution of the chlorine atom in the (3-chloropropyl)-trimethoxysilane with the benzoxazol-2-ylsulfanyl group. The reaction of 2-[(trimethoxysilyl)propylsulfanyl]benzoxazole or –benzothiazole with boron trifluoride etherate led to a previously unknown hydrolytically unstable Si-fluoropropyl derivatives of 2-mercaptobenzoxazole or 2-mercaptobenzothiazole, C6H4N(Y)CS(CH2)3SiF3 (Y = O, S). By transesterification of 2-[(trimethoxysilyl)-propylsulfanyl]benzoxazole by tris(2-hydroxyethyl)amine, a new silatranylpropyl derivative of 2-mercaptobenzoxazole containing an intramolecular coordination bond N→Si and a pentacoordinated silicon atom, C6H4NOCS(CH2)3Si(OCH2CH2)3N, was obtained.

A procedure for simulating gas-dynamic and thermal conditions during the conversion in a radiofrequency induction (RFI) plasma reactor has been developed. The model includes a turbulent flow of a mixture of ideal viscous compressible gases, taking into account inductive heating of the gas through heat conduction, convection, and radiation, considering the effect of the electromagnetic field force on the plasma motion. The formation of powder particles agrees with the results of thermodynamic calculations; the distribution of particles in the flow is described by the diffusion mechanism. The results of the simulation of the conversion of volatile boron chloride and boron fluoride in an RFI plasma torch with vortex-stabilized flow are presented.

Boron trifluoride–etherate (BF3·OEt2) in 2,2,2‐trifluoroethanol (TFE) was found to be a highly efficient promoter system for the intramolecular alkyne–aldehyde metathesis of o-(3-arylpropargyloxy)benzaldehydes. The reaction produces the corresponding 3-aroyl-2H-chromenes in excellent yields under metal-free conditions.

The energy of combination of crystalline boron in gaseous fluorine was measured in a bomb calorimeter. The experimental data combined with reasonable estimates of all known errors may be expressed by the equation: B(c)+3/2F2(g)=BF3(g),ΔHf298°=-271.03±0.51kcal mol-1 This result is compared with other recent work on and related to the heat of formation of boron trifluoride.

Owing to their facile synthesis and desirable optical properties, β-diketones (bdks) are attractive scaffolds for the production of new mechanochromic luminescent (ML) materials. However, ML-active bdk dyes that can access full color luminescent states (i.e., red, green, and blue) have yet to be realized. To synthesize such a set of bdk emitters, two strategies were used to red-shift the emission: substitution with varying donor and acceptor groups; and coordination of BF2 to the β-diketonate moiety. Additionally, 3,4,5-trimethoxy-substituted phenyl rings were used to disrupt the molecular packing to promote ML and enable aggregation-induced emission (AIE). Here, a series of trimethoxy-substituted bdks were prepared via Claisen condensation, each para-substituted with either F, I, or CN groups. Their boronated complexes were synthesized via reaction with boron trifluoride diethyl etherate. Optimized geometries generated from density functional theory calculations indicated that the dye para-substituted me...

A facile, efficient and general synthesis of a broad range of structurally variant alkoxymethylphosphonium tetrafluoroborates (2a–e) is described. The reaction involves the triphenylphosphination of bis-alkoxy methanes in the presence of ethereal boron trifluoride at room temperature. Application of these new salts to carbon homologation of aldehydes is also studied.

A practical method for the direct preparation of diphenylmethyl (DPM) esters from 2-diphenylmethoxypyridine is described. The reaction was readily performed in the presence of a catalytic amount of boron trifluoride-diethyl etherate at room temperature. Using this reaction protocol, various carboxylic acids were converted to DPM esters with high yields. This method is highly effective for the protection of carboxylic acids and the synthesis of DPM esters, and offers a promising approach for facile esterification of a variety of carboxylic acids.

A simple protocol using cationic acetylacetonate palladium complexes with mono-/bidentate phosphine ligands activated with BF 3 ·OEt 2 as in situ -formed catalyst for polymerization of endo/exo mixture of 5-methoxycarbonylnorbornene (activity up to 1.1·10 4 g mol − 1 h − 1 ) or 5-phenylnorbornene (7.2·10 5 g mol − 1 h − 1 ), and norbornene (3.3·10 8 g mol − 1 h − 1 ) have been developed. It was observed that the ligands nature strongly influence the catalytic activity. The catalyst system Pd(II)/BF 3 ·OEt 2 was also active for the copolymerization of norbornene with 5-methoxycarbonylnorbornene. DFT calculations of isomers upon single insertion of 5-methoxycarbonylnorbornene into Pd H bond and NMR/FTIR studies for pre-catalyst activation mechanism were performed.

Boron trifluoride-mediated transformation of tetrahydrofuran to corresponding N-aryl-substituted pyrrolidines is conducted under mild reaction conditions, providing a practical synthetic method with reasonable yields. Computational studies confirmed the reaction mechanism involving a fast Lewis acid-assisted ring-opening step, followed by the 7-membered intermediate formation and a ringclosing process as the rate-determining step.

Two new pyrrolylquinoline-substituted heteroaromatic-containing compounds bearing a central boron bridge have been prepared by a short, high-yielding sequence consisting of Suzuki-coupling of 8-bromoquinoline and N-Boc 2-pyrroleboronic acid, thermolytic tert-butyloxycarbonyl deprotection, and subsequent boron chelation (either using boron trifluoride or triphenylborane). Both derivatives display longer wavelength absorption maxima (λabsmax) than a previously reported indolopyridine-BPh2 analogue, in agreement with the smaller HOMO-LUMO energy gap predicted by DFT quantum chemical calculations. Both of the pyrrolylquinoline-boron chelates display weak emission (quantum yields 0.3–0.9%) and the BPh2 complex displays a very broad, long-wavelength emission (λemmax = 715 nm, MeCN), which may be due to dimer emission and results in a large pseudo-Stokes’ shift (7753 cm−1) for this compound.

Brookhart-type catalytic systems based on zero-valent nickel complexes Ni(COD)2 and Ni(COD)L [where COD is cyclooctadiene and L is bis-2,6-diisopropylphenyl-diazabutadiene (DPP-DAB) or N,N′-bis-2,6- diisopropylphenyl-bis-iminoacenaphthene (DPP-BIAN)] activated with Lewis acids such as methylaluminoxane (MAO) and boron trifluoride etherate BF3·OEt2 were investigated via electron spin resonance (ESR) spectrometry, revealing that presence of diimine ligand results in Lewis acids, formally oxidating Ni(0) to Ni(I). An oxidation mechanism is proposed.

A simple and solvent-free protocol using cationic acetylacetonate palladium complexes with mono-/bidentate phosphine ligands activated with BF3·OEt2 as in situ-formed catalyst for hydroamination of vinylarenes with arylamines have been developed. Excellent catalytic activities were obtained using [Pd(acac)(PPh3)2][BF4]/BF3·OEt2/i-PrOH catalyst system with the addition of a small amount of palladium (0.2–0.05 mol%) to the reaction mixture. Furthermore, the novel unexpected diphosphine-bridged palladium complexes have been prepared and characterized: [Pd(acac)(dpppt)]2[BF4]2 and [Pd(acac)(dpph)]2[BF4]2 (dpppt – 1,5-bis(diphenylphosphino)pentane, dpph – 1,6-bis(diphenylphosphino)hexane)

A series of O,O-chelated boron complexes was prepared through a four-component Ugi reaction followed by complexation of the resulting 1,3-dicarbonyl compounds with boron trifluoride diethyl etherate. The optical properties of these novel luminophores were investigated by UV/Vis spectroscopy and spectrofluorometry, revealing pronounced aggregation-induced emission (AIE) features.

A series of weakly emissive, exited state intramolecular proton transfer active tetrahydrodibenzo[a,i]phenanthridin-5-yl)phenols were efficiently synthesized using 2-tetralone and substituted salicylaldehydes. These dyes were smoothly coordinated with boron trifluoride diethyletherate resulting in π-conjugated and rigid tetracoordinated boron-phenanthridine complexes. The complexes were highly emissive in solution and solid states with large Stokes shift values ranging from 6190 to 10410 cm−1 and moderate fluorescence quantum yields. A systematic photophysical and solvatochromism studies revealed that the intramolecular charge transfer process was more effective in borophenanthridines than with others, which was supported by DFT study. Further, the electrochemical studies testified the high electron-accepting ability of these boron complexes.

The electropolymerization of a ruthenium(II) 2,6-di(quinolin-8-yl)pyridine complex with two pendant bithienyl-groups is investigated in detail. The associated redox potentials enable mild anodic electropolymerization without the need for boron trifluoride diethyl etherate (BFEE), which promotes undesired side reactions. Continuous film growth in the presence of acid or alternative electrolytes is achieved even for large cycle numbers (500), as detailed by the evolution of the peak current densities and the cathodic charge upon re-reduction of the film. The latter analysis permits a complementary analysis, particularly in the case of distorted CVs caused by charge transport limitations within the film. Notably, electropolymerization can also be performed potentiostatically at low anodic (over-)potentials even at prolonged reaction times, which leads to films with enhanced electrochemical properties. A high film porosity of spherical-like agglomeration networks is confirmed by SEM investigations, whereby higher control is found under slower and/or milder electropolymerization conditions. The films show the preserved electrochemical and optical properties of the Ru sensitizer, i.e., a defined and stable redox process, strong UV-vis absorption up to 600 nm, emission in the NIR range, and effective electrochemical switching promoted by the quaterthiophene bridge.

The functionalized 1-ethoxycarbonylmethyl-3-methylimidazolium tetrafluoroborate ([EAMIM]BF4) ionic liquid and the polyvinyl pyrrolidone protected Cu microparticles were synthesized and characterized. The tribological properties were investigated by a four-ball tribometer and the friction mechanisms are also discussed. The results demonstrate both the [EAMIM]BF4 ionic liquid and Cu microparticles possess the excellent tribological behaviors that can remarkably improve the friction-reduction and anti-wear properties of sunflower seed oil. Moreover, the tribochemical reaction film, which consists of copper, copper oxide, iron oxide, iron boride and boron trifluoride etc., was formed on the worn surface. The synergistic lubricating effect was produced and a tribological model of Cu microparticles and [EAMIM]BF4 ionic liquid in the sunflower seed oil was established to explain the lubricating mechanisms.

Lithium 4,4-dimethoxy-1-(perfluoroalkyl)pentane-1,3-dionates react with BF3•Et2O to give 2-methoxy-2-methyl-5-(perfluoroalkyl)furan-3(2H)-ones in high yields.

Enriched boron-10 and its related compounds have great application prospects, especially in the nuclear industry. The chemical exchange rectification method is one of the most important ways to separate the 10B and 11B isotope. However, a real-time monitoring method is needed because this separation process is difficult to characterize. Infrared spectroscopy was applied in the separation device to realize the online determination of the boron isotope ratio in boron trifluoride (BF3). The possibility of determining the isotope ratio via the 2&nu, 3 band was explored. A correction factor was introduced to eliminate the difference between the ratio of peak areas and the true value of the boron isotope ratio. It was experimentally found that the influences of pressure and temperature could be ignored. The results showed that the infrared method has enough precision and stability for real-time, in situ determination of the boron isotope ratio. The instability point of the isotope ratio can be detected with the assistance of the online determination method and provides a reference for the production of boron isotope.

The enantioselective oxyarylation of (E)-6-aryl-1-silyloxylhex-3-ene was achieved using a lactate-based chiral hypervalent iodine(III) reagent in the presence of boron trifluoride diethyl etherate. The silyl ether promotes the oxidative cyclization, and enhances the enantioselectivity. In addition, the corresponding aminoarylation was achieved.

Three complexes with boron trifluoride (BF3) as the Lewis acid and different Lewis bases were synthesized and used as electrolyte additives in Li[Ni1/3Mn1/3Co1/3]O2/graphite and Li[Ni0.42Mn0.42Co0.16]O2/graphite pouch cells. Lewis acid-base adducts with a boron-oxygen (B O) bond were trimethyl phosphate boron trifluoride (TMP-BF) and triphenyl phosphine oxide boron trifluoride (TPPO-BF). These were compared to pyridine boron trifluoride (PBF) which has a boron-nitrogen (B N) bond. The experimental results showed that cells with PBF had the least voltage drop during storage at 4.2 V, 4.4 V and 4.7 V at 40 °C and the best capacity retention during long-term cycling at 55 °C compared to cells with the other additives. Charge-hold-discharge cycling combined with simultaneous electrochemical impedance spectroscopy measurements showed that impedance growth in TMP-BF and TPPO-BF containing cells was faster than cells containing 2%PBF, suggesting that PBF is useful for impedance control at high voltages (>4.4 V). XPS analysis of the SEI films highlighted a specific reactivity of the PBF-derived SEI species that apparently hinders the degradation of both LiPF6 and solvent during formation and charge-hold-discharge cycling. The modified SEI films may explain the improved impedance, the smaller voltage drop during storage and the improved capacity retention during cycling of cells containing the PBF additive.

In this study, the synthesis of boron dipyrromethene dyes containing mono, bis-2-naphthyloxyhexyloxy and 4-(benzyloxy)phenoxyhexyloxy groups has been reported. Boron dipyrromethene dyes were synthesized from the mono, bis-benzaldehyde derivatives with 2,4-dimethylpyrrole in dichloromethane in the presence of trifluoroacetic, 2,3-dichloro-5,6-dicyano-p-benzoquinon, triethyl amine and boron trifluoride diethyl etherate, respectively. Electrochemical characterization of boron dipyrromethene dyes were carried out with voltammetric measurements. Electrochemical studies show that boron dipyrromethene dyes containing mono, bis-2-naphthyloxyhexyloxy and 4-(benzyloxy)phenoxyhexyloxy groups have reversible one reduction potentials unlike irreversible one oxidation potentials. Graphical Abstract ᅟ.

The ring-opening of cyclopropane-1,1-dicarboxylates with vicinal donor aryl groups by boronic acids and potassium organotrifluoroborates under metal-free conditions has been developed. The reaction utilizes trifluoroacetic acid or boron trifluoride as promoters.

A novel boron–silicon–alkynyl hybrid copolymer (BSD) was synthesized by condensation polymerization of 1,3-diethynylbenzene with dichloromethylsilane and boron trifluoride etherate. Fourier transform infrared and 1H-, 13C-, and 29Si-nuclear magnetic resonance spectroscopies were used to confirm the structures of the copolymers. Thermogravimetric analysis and differential scanning calorimetry showed that the polymer exhibited excellent heat resistance and thermo-oxidative stabilities under nitrogen and air. The cure cross-linking reaction mechanisms of the BSD were related to Diels–Alder intermolecular cyclization involving two C≡C bonds and hydrosilylation reaction between Si–H and C≡C bonds. The [Formula: see text] of the BSD was above 591°C and 530°C under nitrogen and air, respectively. The residues at 1000°C were above 88% under nitrogen and 25% in air. X-ray diffraction was used to study the formation of ceramics. The precursor for ceramics (β-SiC, α-SiC, and B4C) was formed at 1600°C under an argon atmosphere. The thermo-oxidative stabilities of the copolymers were attributed to the existing organic groups of alkynyl and inorganic elements of silicon and boron.

A boron trifluoride–methanol complex demonstrated remarkable deprotection selectivity against commonly used amino-protecting groups in the deacetylation of acetanilides and high sensitivity to the steric hindrance of substrates. The scope and limitations of the reaction were explored.

Substituted morpholines have been efficiently synthesised in good yields from nitrogen tethered alkanol-epoxide mediated by boron trifluoride etherate. The methodology has been used for the total synthesis of (±)-viloxazine.

A method was proposed to determine boron trifluoride in boron trifluoride complex using fluoride ion selective electrode(ISE). Hydroxide was chosen to mask aluminum for the determination of 0.01—0.1 mol/L of fluoride. The simulation indicated that the permissible aluminum masked at a certain pH value was limited and hardly related to F-concentration and boric acid. It is better to control pH value below 11.5 and the aluminum concentration within 0.025 mol/L to minimize the interference of hydroxide to the fluoride ISE. The decomposition conditions of boron trifluoride by aluminum chloride were investigated. It is found that the F-detection ratio will approach 1.0 if the Al/F molar ratio is 0.3—0.7 and aluminum concentration is no more than 0.02 mol/L when heated at 80 °C for 10 min. In one word, hydroxide is quite fit to mask aluminum for samples which contain high content of fluoride and aluminum and the BF3 content can be successfully determined by this method.

Isothermal microcalorimetry can be used in conjunction with electrochemical measurements to study solid-electrolyte interphase (SEI) formation reactions as they occur in a Li-ion cell. The heat flow was measured in wound cells that contained no electrolyte additives and in cells prepared with four additives that are known to produce an SEI at the negative electrode surface: vinylene carbonate (VC), fluoroethylene carbonate (FEC), pyridine boron trifluoride (PBF), and prop-1-ene-1,3-sultone (PES). For VC, two distinct features in the differential capacity (dQ/dV vs. Q) plot that align with overlapping peaks in the heat flow plot do not agree with a simple one-electron reduction followed by anionic polymerization. For FEC, three distinct differential capacity and calorimetric peaks are observed. Heat flow measurements at multiple PBF concentrations show that PBF reduction does not significantly affect the reduction of EC at higher cell voltage. The total heat flow during SEI formation in PBF- and PES-containing cells match the calculated energies in recently published reaction pathways. It is concluded that IMC may be used to study the underlying chemistry of SEI formation, especially when paired with computational studies.

Ultrapure highly crystalline magnesium fluoride (MgF2) nanowires with high aspect ratios were successfully synthesized by utilizing ammonium boron trifluoride (NH3BF3) as a precursor material for the first time. Our results reveal that when the vapors of NH3BF3 react with magnesium chloride (MgCl2), a perfect crystalline MgF2 phase can be obtained on a large scale. The MgCl2 utilized in this study plays a crucial role in nanowire growth and morphology control, resulting in ultrapure and highly crystalline MgF2 nanowires. The prepared nanowires have an average diameter of 60 nm and lengths up to tens of micrometers. Property studies indicate that the MgF2 nanowires are completely transparent in nature as confirmed by UV-Vis spectroscopy. We believe that these nanowires provide promising building blocks for the future optical nanodevices.

This paper reports a novel method of boron doped titania nanotube arrays preparation by electrochemical anodization in electrolyte containing boron precursor – boron trifluoride diethyl etherate (BF 3 C 4 H 10 O), simultaneously acting as an anodizing agent. A pure, ordered TiO 2 nanotubes array, as a reference sample, was also prepared in solution containing a standard etching compound: ammonium fluoride. The doped and pure titania were characterized by scanning electron microscopy, UV–vis spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, photoluminescence emission spectroscopy and by means of electrochemical methods. The B-doping decidedly shifts the absorption edge of TiO 2 nanotubes towards the visible light region and significantly inhibits the radiative recombination processes. Despite the fact that the doped sample is characterized by 4.6 lower real surface area when compared to pure titania, it leads to the decomposition of methylene blue in 93%, that is over 2.3 times higher than the degradation efficiency exhibited by the undoped material. The formation rate of hydroxyl radicals ( OH) upon illumination significantly favours boron doped titania as a photocatalytic material. Moreover, the simple doping of TiO 2 nanotubes array results in the enhancement of generated photocurrent from 120 μA/cm 2 to 350 μA/cm 2 registered for undoped and doped electrode, respectively.

Some (tetrahydroimidazo[1,5-a]pyridin-3-yl)phenols were reacted with boron trifluoride diethyl etherate and the resulting BF2-functionalized compounds were fully characterized both in solution using 1H, 13C, 11B, 19F NMR spectroscopy and in the solid state (infrared, fluorescence, X-ray). When excited with UV light these boron difluoride derivatives show in dichloromethane solution an intense fluorescence emission in the UV region, with λmax of emission varying from 357 to 390 nm. Good absolute quantum yields are recorded for most of the compounds. In the solid state, they are characterized by a strong blue emission (388–435 nm), with high absolute quantum yields (up to 0.68) and x,y color coordinates (CIE 1931) close to those expected for standard blue. Time-Dependent Density Functional Theory (TD-DFT) calculations were used to define the nature of the electronic transitions and excited states involved in the fluorescence process.

Covalent functionalization is a way to tune the electrochemical properties of hexagonal boron nitride (h-BN) monolayers. The wide band gap insulator h-BN may become metallic conductor upon functionalization with strong oxidants, such as fluorosulfonyl radicals ($\cdot$OSO$_2$F), as known since 1978 [N. Bartlett et al., J. Chem. Soc. Chem. Comm. {\bf 5}, 200 (1978)], with electrical conductivity of 1.5 S/cm [C. Shen et al., J. Solid State Chem. {\bf 147}, 74 (1999)] that greatly surpasses commercial cathode material Li$_{x}$CoO$_{2}$ while retaining excellent ionic conductivity. Functionalized boron nitrides (FBN-s) have great potential for cathode applications in energy storage devices, for example in solid state batteries. While fluorosulfonyl functionalization is unlikely to result in rechargeable cathodes, similarly to graphene fluoride (CF$_x$), some other FBN-s discussed here may do. In the present work, fluorene, oxygen and combined oxygen and boron trifluoride functionalizations are studied, on the basis of band structure calculations. Due to the open surfaces of FBN-s, fast ionic diffusion with Li, Na and Mg ions is possible, enabling batteries with voltages of 2.1-5.6 V, theoretical energy densities of 800-1200 Wh/kg and fast charge and discharge., Comment: submitted for publication

A focus of the semiconductor industry on advanced devices and equipment is expected, but many fabs are also at full capacity with legacy node technology. This results in hundreds of older generation ion implanter tools still being used for semiconductor manufacturing processing. The expectation for better yields and lower cost of ownership is always important no matter the technology node. Fluoride gases, including BF 3 , have a long history of poor ion source life performance due to tungsten transport from halogen cycling inside the arc chamber. This paper will demonstrate the advantages of mixing only hydrogen (H 2 ) with enriched 11Boron Trifluoride to increase source life on an Applied Materials (Varian) E-500 ion implant tool. The use of a single subatmospheric cylinder to provide this benefit, makes converting from pure 11Boron Trifluoride to the Entegris 11Boron Trifluoride mixture simple, easy to maintain, and safe.

An efficient approach for the double acetylation of 5,11-dihexyl-6,12-di(hetero)aryl-substituted 5,11-dihydroindolo[3,2-b]carbazoles with acetic anhydride in the presence of boron trifluoride etherate has been developed, thus affording the corresponding 2,8-diacetyl derivatives in good yields. A similar acylation has been shown to occur by the reaction of anhydrides of other carboxylic acids. Oxidation of the obtained 2,8-diacetyl derivatives with selenium dioxide takes place on heating or under microwave irradiation, thus resulting in the formation of the corresponding 2,8-diglyoxals. The latter proved to react with aromatic o-diamines to afford new indolo[3,2-b]carbazoles bearing quinoxalinyl fragments at C-2 and C-8. Major optical properties of quinoxaline-containing indolo[3,2-b]carbazoles have been measured.

A simple and efficient one-pot preparation of α-ketoacetals from substituted acetophenones and triethylorthoformate in the presence of H2SeO3 and BF3·Et2O as catalyst has been developed. The desired products are obtained in good yields by a simple protocol involving neat and mild reaction conditions. The present methodology provides an attractive alternative method for the preparation of α-ketoacetal derivatives.

The reactions of boron trifluoride with the organostannylene RSnCl {R = 4-tBu-2,6-[P(O)(OiPr)2]2C6H2} and the organosilane RSiMe3 provided the corresponding 1:1 and 1:2 complexes, respectively, through the formation of P=OB interactions. In the former reaction, even with excess BF3·OEt2, no SnB complexation involving the lone electron pair at the tin(II) center was observed. The experimental results are supported by DFT calculations.

Oxazoles and aryl sulfides are chemical entities that are found in many natural products and biologically and pharmaceutically active molecules. It is therefore highly desirable to develop an efficient and practical approach to the synthesis of arylsulfanyl-substituted oxazolines. We developed a simple and efficient method for boron-catalyzed sequential arylsulfanylation and oxygenation of N-allylamides. The protocol uses readily available 1-(arylsulfanyl)pyrrolidine-2,5-diones as the arylsulfanylation reagents and inexpensive boron trifluoride etherate as the catalyst; no ligands or additives are required, and it is not necessary to purge the reaction vessel of air. The method therefore provides an efficient and practical strategy for the synthesis of arylsulfanyl-substituted heterocycles.

A series of novel electrolyte additives based on Lewis acid/base adducts has been designed and successfully synthesized. The synthesis is very simple: a pyridine derivative is mixed with boron trifluoride dissolved in diethyl ether to yield a solid crystalline product. The effect of Pyridine-Boron Trifluoride (PBF) and its derivatives have been thoroughly evaluated in Li[Ni1/3Mn1/3Co1/3]O2/graphite and Li[Ni0.42Mn0.42Co0.16]O2/graphite pouch cells. Evaluation experiments, including high voltage storage, gas production, electrochemical impedance spectroscopy measurements, ultra high precision cycling and long-term cycling were carried out on cells containing the novel additives. The results were compared to baseline experiments on cells with well-known additives such as vinylene carbonate (VC), prop-1-ene sultone (PES), methylene methane disulfonate (MMDS), tris(-trimethyl-silyl)-phosphite (TTSPi) and triallyl phosphate (TAP). The PBF additives are competitive with all known additives in NMC/graphite cells, which, combined with their low cost and facile synthesis, suggest this series of novel additives will be useful in high-voltage/high-temperature lithium ion battery applications. The PBF additives yield cells which show excellent capacity retention and maintain low impedance during high voltage cycling, in contrast to cells containing VC.

A ring-opening coupling reaction of D–A cyclopropenes and nitriles is described for the facile synthesis of γ-amino ketones. The co-catalytic system combining copper(I) and boron trifluoride would be inspiring because it disfavors the [3 + 2] cycloaddition to turn the selectivity over the Ritter process.

Composites based on ultradispersed polytetrafluoroethylene and intercalated graphite oxide compounds with dodecahydro-closo-dodecaborates and methods of their fabrication have been developed. The fabricated composites have been characterized using XRD analysis, and optical microscopy. These composites are distinguished with completeness of their combustion, since the combustion products comprise gaseous boron fluorine-containing compounds of boron, boron trifluoride (BF3), and boron oxyfluoride ((BOF)3). Besides, these composites are characterized with increased energy capacity as compared to purely oxygen-containing compounds, since the heat of formation of boron fluorine-containing compounds is higher than that of boron oxide. Introduction of ultradispersed polytetrafluoroethylene imparts composites with hydrophobicity, thus improving their functioning properties.

Six new bis-β-diketones (RCOCH2CO-C7H7N-COCH2COR) were synthesized from 3,5-diacetyl-2,6-dimethylpyridine via Claisen condensation with the corresponding esters, and then reacted with boron trifluoride etherate to afford difluoroboron bis-β-diketonate derivatives. Their spectroscopic properties were investigated by UV–vis, FTIR, 1H NMR and fluorescence spectroscopic techniques. It was found that these boron complexes exhibited violet or blue fluorescence emission at 422–445 nm and possessed high extinction coefficients. The results indicate that the extending π-conjugation can increase the fluorescence intensity and quantum yield for these boron complexes. Especially, the compound 2b displayed the stronger fluorescence intensity and the highest fluorescence quantum yield (Φu = 0.94) in these boron compounds. However, compounds 2c and 2d had the lower fluorescence intensity and quantum yield as a result of the heavy atom effect of the chlorine atom in the molecules.

Although methods of boron isotopes separation were intensively pursued about 60 years, the chemical exchange distillation is the only method that has been applied in industrial scale production of 10B. The present anisole BF3 system suffers from the drawbacks like high melting point, relatively low separation coefficient and instability under reaction conditions, which demand a continuous search for more effective and efficient donors for boron isotope separation. A series of fluoro-substituted anisole derivatives were screened in this paper, among which 2,4-difluoro anisole exhibited good properties compared with anisole. Studies on the boron trifluoride and 2,4-difluoro anisole adduct, its thermodynamic and physical properties related to large-scale isotopic separation is reported. The results showed that 2,4-difluoro anisole is better than anisole in separation coefficient, freezing point and stability under pyrolysis conditions, which suggest a further detailed investigations on boron trifluoride and 2,4-difluoro anisole adduct.

A widely used Lewis acid BF3·Et2O was shown to be capable of acting as an efficient fluorinating agent in an intramolecular aminofluorination reaction of homoallylic amines to provide 3-fluoropyrrolidines mediated by a commercially available hypervalent iodine(III) reagent PhIO at room temperature. A mechanism involving a carbocation intermediate was proposed on the basis of several experimental evidence.

The lithiation of 2-picoline (1a) and 2,3-lutidine (1b) in diethyl ether has been investigated with and without prior complexation with BF3. The reactions of the BF3 adduct of these moieties (2a and 2b) with lithium diisopropylamide (LDA) and subsequent trapping with benzaldehyde or dimethyl disulfide gave products corresponding to exclusive lithiation at the α-methyl carbon. The yields obtained with these reactions were far superior to that obtained with the lithiation of uncomplexed 1a and 1b. The dilithiation of 2a and 2b has also been investigated and a convenient and efficient synthesis of the diiodo derivatives of 1,2-bis(pyridin-2-yl)ethane has been provided.

The catalytic characteristics of the individual complex Ni(PPh3)2(C2H4) and Ni(PPh3)nCl (n = 2 or 3) and those of systems based on these complexes in combination with Bronsted and Lewis acids in ethylene and propylene oligomerization have been determined. A correlation between the BF3 · OEt2 solution storage time and the catalytic properties of the nickel systems has been established for the reactions of the lower alkenes. The observed increase in the turnover frequency and turnover number of the catalyst is due to the increase in the Brorsted acid concentration as a result of irreversible conversions of BF3 · OEt2 caused by its interaction with impurity water in the solvent. The formation of the Ni(PPh3)2(C2H4)-BF3 · OEt2 catalytic system in the presence of a substrate dramatically extends the system’s service life. The interaction of the nickel precursors with boron trifluoride etherate has been investigated using a complex of physical methods, and the main reactions yielding catalytically active species have been revealed.