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A new concept for the synthesis of dialkyl chloronium cations [R−Cl−R]+ is described (R=CH3, CH2CF3), that allows the formation of fluorinated derivatives. By utilizing the xenonium salt [XeOTeF5][M(OTeF5)n] (M=Sb, n=6; M=Al, n=4) chlorine atoms of chloroalkanes or the deactivated chlorofluoroalkane CH2ClCF3 are oxidized and removed as ClOTeF5 leading to the isolation of the corresponding chloronium salt. Since the resulting highly electrophilic cation [Cl(CH2CF3)2]+ is able to alkylate weak nucleophiles, this compound can be utilized for the introduction of a fluorinated alkyl group to those. In addition, the fluorinated alkyl chloronium cation displays a high hydride ion affinity, enabling the activation of linear hydrocarbons by hydride abstraction even at low temperatures ultimately leading to the formation of branched carbocations. [ABSTRACT FROM AUTHOR]

A practical and efficient trifluoromethylation of readily available and bench stable N‐Thiophthalimides and N‐Thioimides with Ruppert‐Prakash reagent (TMS‐CF3) is described. The reaction proceeds at room temperature and only requires NaOAc as the mild promoter to prepare a series of trifluoromethyl thioethers in good to excellent yields. Both aryl and alkyl derivates are well trifluoromethylated under transition‐metal‐free reaction conditions. Moreover, the reaction features with scale‐up synthesis and late‐stage modification of bioactive molecule. [ABSTRACT FROM AUTHOR]

The structure of cis‐ or trans‐bridged [GeF5]− anionic chains have been investigated [Mallouk et al. (1984). Inorg. Chem.23, 3160–3166] showing the first crystal structures of μ‐F‐bridged pentafluorogermanates. Herein, we report the second crystal structure of trans‐pentafluorogermanate anions present in the crystal structure of sodium trans‐pentafluorogermanate(IV) bis(hydrogen fluoride), Na[GeF5]·2HF. The crystal structure [orthorhombic Pca21, a = 12.3786 (3), b = 7.2189 (2), c = 11.4969 (3) Å and Z = 8] is built up from infinite chains of trans‐linked [GeF6]2− octahedra, extending along the b axis and spanning a network of pentagonal bipyramidal distorted Na‐centred polyhedra. These [NaF7] polyhedra are linked in a trans‐edge fashion via hydrogen fluoride molecules, in analogy to already known sodium hydrogen fluorides and potassium hydrogen fluorides. [ABSTRACT FROM AUTHOR]

The reactivity of carbamoyl radicals, generated in situ from sodium oxamate salts, has been investigated in the context of radical carbofluorination reactions of olefins and α‐fluoroolefins, respectively. Both transformations are catalyzed by silver salts and required the presence of potassium persulfate (K2S2O8) and SelectfluorTM as a radicophilic fluorine source. The reported methods provide a direct access to β‐fluoroamides and β,β‐difluoroamides. [ABSTRACT FROM AUTHOR]

The fluoroalkoxy groups (ORf) are widely used motifs in pharmaceutical and agrochemical fields due to their unique physicochemical properties including higher lipophilicity and increased metabolic stability. Thus, the high value of ORf‐containing derivatives has stimulated the development of fluoroalkoxylation reactions. In this review, we highlight the recent progress of various trifluoroalkoxylating reagents and their applications in organic synthesis in the past five years. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The development of switchable solvent‐free multicomponent reactions to build high‐value‐added products is an important demand for organic synthesis. Herein, we detailed the successful implementation of a switchable strategy for the construction of diverse 4‐fluoroalkyl‐1,4‐dihydropyrimidines and 4‐fluoroalkyl‐pyrimidines via a solvent/additive‐free [3 + 2 + 1] annulation, starting from readily available enamines, trifluoroacetaldehyde hydrate or 1‐ethoxy‐2,2‐difluoroethanol and amidines hydrochloride. This reaction conforms to the concept of green synthesis, and provides a new avenue to access valuable fluorinated heterocycles. [ABSTRACT FROM AUTHOR]

Herein we report a general access to silver(i) perfluoroalcoholates, their structure in the solid state and in solution, and their use as transfer reagents. The silver(i) perfluoroalcoholates are prepared by the reaction of AgF with the corresponding perfluorinated carbonyl compounds in acetonitrile and are stable for a prolonged time at −18 °C. X‐ray analysis of single crystals of perfluoroalcoholate species showed that two Ag(i) centers are bridged by the alcoholate ligands. In acetonitrile solution, Ag[OCF3] forms different structures as indicated by IR spectroscopy. Furthermore, the silver(i) perfluoroalcoholates can be used as easy‐to‐handle transfer reagents for the synthesis of Cu[OCF3], Cu[OC2F5], [PPh4][Au(CF3)3(OCF3)], and fluorinated alkyl ethers. [ABSTRACT FROM AUTHOR]

Anhydrous hydrogen fluoride (AHF), a critical raw material for industries such as aluminum, pharmaceuticals, and petroleum, has traditionally been sourced from fluorite--a non-renewable mineral. The unsustainable reliance on fluorite has catalyzed the search for alternative AHF production methods. A promising substitute is fluorosilicic acid (FSA), a byproduct of the phosphate fertilizer industry previously deemed waste. Transforming fluorosilicic acid into AHF not only yields a valuable resource but also addresses the environmental and economic challenges associated with waste management. The innovative practice of producing AHF from fluorosilicic acid signals a shift towards sustainable chemical production by capitalizing on waste, potentially diminishing reliance on fluorite and reducing the industry's environmental impact. This review thoroughly dissects the AHF synthesis process from fluorosilicic acid. Despite the acknowledged importance of fluorinated compounds in numerous industrial applications, research on their synthesis from fluorosilicic acid is limited and fragmented. This review seeks to amalgamate this scattered information by closely scrutinizing diverse industrial processing methods. Additionally, it explores the current and future landscape, economic feasibility, and strategies to navigate the obstacles inherent in synthesizing AHF from fluorosilicic acid. It also assesses the environmental impact of these methods, thereby contributing to the dialogue in this emerging field. The primary aim of this manuscript is to foster further research and promote the industrial uptake of this sustainable process. Highlighting the challenges and proposing potential improvements, the review supports the responsible reuse of waste and advocates for advancements in industrial practices. [ABSTRACT FROM AUTHOR]

Given the profound effect of fluorine‐containing groups in improving the chemical, physical, and biological properties of the parent compound, the fluorine‐containing groups were receiving increasing attention in the medicinal, pharmaceutical, agricultural, and material sciences. Unlike well‐developed trifluoromethylation and difluoromethylation reactions, the efficient and mild methods for rapid introduction of CF2Me are still underdeveloped, despite their important applications in pharmaceuticals and agrochemicals. This concept describes recent progress in difluoroethylation functionalization. [ABSTRACT FROM AUTHOR]

Owing to its unique physical properties, fluorine is often used to open up new reaction channels. In this report, we establish a cooperation of [5,5]‐rearrangement and fluorine‐assisted temporary dearomatization for arene multi‐functionalization. Specifically, the [5,5]‐rearrangement of fluoroaryl sulfoxides with β,γ‐unsaturated nitriles generates an intriguing dearomatized sulfonium species which is short‐lived but exhibits unusually high electrophilicity and thus can be instantly trapped by nucleophiles and dienes at a remarkably low temperature (−95 °C) to produce four types of valuable multi‐functionalized benzenes, respectively, involving appealing processes of defluorination, desulfurization, and sulfur shift. Mechanistic studies indicate that the use of fluorine on arenes not only circumvents the generally inevitable [3,3]‐rearrangement but also impedes the undesired rearomatization process, thus provides a precious space for constructing and elaborating the temporarily dearomatized fluorinated sulfonium species. [ABSTRACT FROM AUTHOR]

Owing to its unique physical properties, fluorine is often used to open up new reaction channels. In this report, we establish a cooperation of [5,5]‐rearrangement and fluorine‐assisted temporary dearomatization for arene multi‐functionalization. Specifically, the [5,5]‐rearrangement of fluoroaryl sulfoxides with β,γ‐unsaturated nitriles generates an intriguing dearomatized sulfonium species which is short‐lived but exhibits unusually high electrophilicity and thus can be instantly trapped by nucleophiles and dienes at a remarkably low temperature (−95 °C) to produce four types of valuable multi‐functionalized benzenes, respectively, involving appealing processes of defluorination, desulfurization, and sulfur shift. Mechanistic studies indicate that the use of fluorine on arenes not only circumvents the generally inevitable [3,3]‐rearrangement but also impedes the undesired rearomatization process, thus provides a precious space for constructing and elaborating the temporarily dearomatized fluorinated sulfonium species. [ABSTRACT FROM AUTHOR]

The NMR technique is among the most powerful analytical methods for molecular structural elucidation, process monitoring, and mechanistic investigations; however, the direct analysis of complex real‐world samples is often hampered by crowded NMR spectra that are difficult to interpret. The combination of fluorine chemistry and supramolecular interactions leads to a unique detection method named recognition‐enabled chromatographic (REC) 19F NMR, where interactions between analytes and 19F‐labeled probes are transduced into chromatogram‐like 19F NMR signals of discrete chemical shifts. In this account, we summarize our endeavor to develop novel 19F‐labeled probes tailored for separation‐free multicomponent analysis. The strategies to achieve chiral discrimination, sensitivity enhancement, and automated analyte identification will be covered. The account will also provide a detailed discussion of the underlying principles for the design of molecular probes for REC 19F NMR where appropriate. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The trifluoromethoxy functional group has received increasing attention in recent years due to its distinctive properties such as good metabolic stability, appropriate lipophilicity and special electrical properties. Thus, the development of new reagents and new strategies of direct trifluoromethoxylation are attracting the enthusiasm of many fluorine chemical workers. At present, nucleophilic and radical trifluoromethoxylating reagents have made major breakthroughs, greatly promoting the development of trifluoromethoxy chemistry. This review is mainly divided into two parts: nucleophilic and radical types, focusing on the development history, characteristics and applications of various trifluoromethoxylating reagents. [ABSTRACT FROM AUTHOR]

Here, we report a general approach to the synthesis of the difluoroalkyl bicycloalkanes (CF2‐BCAs), as structural surrogates of aryl ketones and ethers. The chemistry is driven by a dihydrobenzoacridine photocatalyst, that engages in a catalytic electron‐donor acceptor (EDA) complex, or directly reduces the fluorinated substrate. These two convergent manifolds lead to the generation of the R‐CF2 radical, that reacts with the [1.1.1]‐ or [3.1.1.]‐propellane. The method is extremely general, and extendable to complex bioactive molecules (30 examples, up to 87 % yield). The structural features of the CF2‐BCP hybrid bioisostere were investigated by single crystal X‐ray. Finally, we synthesised a CF2‐BCP analogue of a Leukotriene A4 hydrolase inhibitor, replacing the original aryl ether motif. In silico docking studies indicated that this new analogue maintains the same arrangement within the enzyme pocket, profiling the use of the CF2‐BCA hybrid bioisostere in medicinal chemistry settings. [ABSTRACT FROM AUTHOR]

Here, we report a general approach to the synthesis of the difluoroalkyl bicycloalkanes (CF2‐BCAs), as structural surrogates of aryl ketones and ethers. The chemistry is driven by a dihydrobenzoacridine photocatalyst, that engages in a catalytic electron‐donor acceptor (EDA) complex, or directly reduces the fluorinated substrate. These two convergent manifolds lead to the generation of the R‐CF2 radical, that reacts with the [1.1.1]‐ or [3.1.1.]‐propellane. The method is extremely general, and extendable to complex bioactive molecules (30 examples, up to 87 % yield). The structural features of the CF2‐BCP hybrid bioisostere were investigated by single crystal X‐ray. Finally, we synthesised a CF2‐BCP analogue of a Leukotriene A4 hydrolase inhibitor, replacing the original aryl ether motif. In silico docking studies indicated that this new analogue maintains the same arrangement within the enzyme pocket, profiling the use of the CF2‐BCA hybrid bioisostere in medicinal chemistry settings. [ABSTRACT FROM AUTHOR]

The pentafluoroorthotellurate group (teflate, OTeF5) is able to form species, for which only the fluoride analogues are known. Despite nickel fluorides being widely investigated, nickel teflates have remained elusive for decades. By reaction of [NiCl4]2− and neat ClOTeF5, we have synthesized the homoleptic [Ni(OTeF5)4]2− anion, which presents a distorted tetrahedral structure, unlike the polymeric [NiF4]2−. This high‐spin complex has allowed the study of the electronic properties of the teflate group, which can be classified as a weak/medium‐field ligand, and therefore behaves as the fluoride analogue also in ligand‐field terms. The teflate ligands in [NEt4]2[Ni(OTeF5)4] are easily substituted, as shown by the formation of [Ni(NCMe)6][OTeF5]2 by dissolving it in acetonitrile. Nevertheless, careful reactions with other conventional ligands have enabled the crystallization of nickel teflate complexes with different coordination geometries, i.e. [NEt4]2[trans‐Ni(OEt2)2(OTeF5)4] or [NEt4][Ni(bpyMe2)(OTeF5)3]. [ABSTRACT FROM AUTHOR]

Summary: Fluorine, as the most electronegative element, provides the highest electrode potential when it undergoes redox reactions. Moreover, fluoride ion is intrinsically an excellent charge carrier in both electrolytes and electrode structures owing to its small size, low atomic weight, and good ionic mobility. Hence, batteries based on fluorine electrochemistry, the so‐called fluoride ion batteries (FIBs), have recently been deemed as an alternative next‐generation high energy density battery system. This article reviews the recent progress in FIBs based on liquid electrolytes. The mechanisms, advantages, and drawbacks of FIBs are discussed. In the end, the perspective illuminating the research directions for further development is presented. [ABSTRACT FROM AUTHOR]

Preparation and characterization of the dimeric Lewis superacid [Al(OTeF5)3]2 and various solvent adducts is presented. The latter range from thermally stable adducts to highly reactive, weakly bound species. DFT calculations on the ligand affinity of these Lewis acids were performed in order to rank their remaining Lewis acidity. An experimental proof of the Lewis acidity is provided by the reaction of solvent‐adducts of Al(OTeF5)3 with [PPh4][SbF6] and OPEt3, respectively. Furthermore, their reactivity towards chloride and pentafluoroorthotellurate salts as well as (CH3)3SiCl and (CH3)3SiF is shown. This includes the formation of the dianion [Al(OTeF5)5]2−. [ABSTRACT FROM AUTHOR]

A simple and convenient eosin Y-catalyzed procedure has been developed to effect metal-free, visible-light mediated chlorotrifluoromethylation of terminal alkenes with CF3SO2Cl. Several substrates with terminal alkenes including an aromatic heterocycle reacted smoothly to afford various chlorotrifluoromethylated compounds in good to excellent yields. [ABSTRACT FROM AUTHOR]

An approach for the distal construction of a C(sp3)−SCF2R bond on aliphatic alcohols enabled by 1,5‐hydrogen‐atom transfer (HAT) was developed. In the presence of a hypervalent iodine (PIDA) and readily available ArSO2SCF2R reagents, this transition metal‐free approach allowed the remote functionalization of a broad variety of alcohols with emergent and high added‐value SCF2R moieties (R=H, F, CO2Et and PO(OEt)2) under blue light irradiation. [ABSTRACT FROM AUTHOR]

A systematic study of halogenate(I/III) anions with polyatomic ligands is presented. The bis(perfluoro‐tert‐butoxy) halogenates(I) [X(OC4F9)2]−, X=Cl, Br, I, of chlorine, bromine, and iodine are prepared as their tetraethylammonium salts and characterized with IR, Raman, and NMR spectroscopic methods, as well as single‐crystal X‐ray diffraction analyses. Spectroscopical data are supported by quantum‐chemical calculations. Additionally, the bonding situation of the species in question are analyzed and discussed. Furthermore, the oxidation to the corresponding halogenate(III) derivatives was studied. For [Br(OC4F9)2]−, oxidation with elemental fluorine gave [BrF2(OC4F9)2]−. Iodide was directly oxidized by ClOC4F9 to the IIII species [I(OC4F9)4]−, which is a surprisingly inert anion that might be used as a weakly coordinating anion (WCA) in the future. For [Cl(OC4F9)2]−, the decomposition products of the synthetic approaches towards a chlorine(III) system were analyzed. [ABSTRACT FROM AUTHOR]

Porous materials are important for various energy‐related technologies such as catalysis and separation. While porous organic cage compounds are a rather recent addition to the field of porous materials, these discrete nanocavities have since emerged as a versatile functional‐materials platform, facilitated by the solubility of the materials in common organic solvents. In contrast to other frameworks, organic cages are assembled first from modular building blocks in solution and then packed in the solid‐state in a next step. In this minireview, we highlight examples of porous organic cages with focus on how the intrinsic nanopore can be controlled and utilized, especially focusing on their synthesis and the gas sorption properties of smaller intrinsic pores of porous organic cage compounds, porous macrocycles, and other related compounds. [ABSTRACT FROM AUTHOR]

A chemical method for the treatment of harmful halogenated compounds that has recently become of interest is the reductive dehalogenation of carbon‐halogen bonds. In the case of a fluorine atom, this process is called hydrodefluorination. While many transition metal‐based approaches now exist to reductively defluorinate aromatic fluoroarenes, the cleavage of C−F bonds in aliphatic compounds is not so well‐developed. Here we propose a biocatalytic approach exploiting a promiscuous activity exhibited by transaminases (TAs). Hence, a series of α‐fluoroketones have been defluorinated with excellent conversions using Chromobacterium violaceum and Arthrobacter sp. TAs under mild conditions and in aqueous medium, using a stoichiometric amount of an amine (e. g. 2‐propylamine) as reagent and formally releasing its oxidized form (e. g. acetone), with ammonia and hydrogen fluoride as by‐products. It is also demonstrated that this process can be performed in a regio‐ or stereoselective fashion. [ABSTRACT FROM AUTHOR]

The regioselective 2,2,2‐trifluoroethoxylation at the C5 position of amides derived from the 8‐aminoquinoline has been developed. In the presence of PIDA, an unprecedented and undirected transition metal‐free transformation was achieved using the readily available and appealing 2,2,2‐trifluoroethanol as the fluorinated source. The selective distal 2,2,2‐trifluoroethoxylation of an array of amides was achieved in moderate to good yields (12 examples, up to 61 % yield). This approach provided efficient access to high‐value added fluorinated quinoline derivatives, key building blocks for bulk and fine chemical industry. [ABSTRACT FROM AUTHOR]

To create innovative materials, efficient control and engineering of pore sizes and their characteristics, crystallinity and stability is required. Eight hybrid Tri4Di6 imine cages with a tunable degree of fluorination and one fully fluorinated Tri4Di6 imine cage are investigated. Although the fluorinated and the non‐fluorinated building blocks used herein differ vastly in reactivity, it was possible to gain control over the outcome of the self‐assembly process, by carefully controlling the feed ratio. This represents the first hybrid material based on fluorinated/hydrogenated porous organic cages (POCs). These cages with unlimited miscibility in the solid state were obtained as highly crystalline samples after recrystallization and even showed retention of the crystal lattice, forming alloys. All mixtures and the fully fluorinated Tri4Di6 imine cage were analyzed by MALDI‐MS, single‐crystal XRD, powder XRD and in regard to thermal stability (TGA). [ABSTRACT FROM AUTHOR]

The coordination chemistry of KrF2 has been limited in contrast with that of XeF2, which exhibits a far richer coordination chemistry with main‐group and transition‐metal cations. In the present work, reactions of [XeF5][AsF6] with KrF2 in anhydrous HF solvent afforded [F5Xe(FKrF)AsF6] and [F5Xe(FKrF)2AsF6], the first mixed krypton/xenon compounds. X‐ray crystal structures and Raman spectra show the KrF2 ligands and [AsF6]− anions are F‐coordinated to the xenon atoms of the [XeF5]+ cations. Quantum‐chemical calculations are consistent with essentially noncovalent ligand−xenon bonds that may be described in terms of σ‐hole bonding. These complexes significantly extend the XeF2–KrF2 analogy and the limited chemistry of krypton by introducing a new class of coordination compound in which KrF2 functions as a ligand that coordinates to xenon(VI). The HF solvates, [F5Xe(FH)AsF6] and [F5Xe(FH)SbF6], are also characterized in this study and they provide rare examples of HF coordinated to xenon(VI). [ABSTRACT FROM AUTHOR]

The coordination chemistry of KrF2 has been limited in contrast with that of XeF2, which exhibits a far richer coordination chemistry with main‐group and transition‐metal cations. In the present work, reactions of [XeF5][AsF6] with KrF2 in anhydrous HF solvent afforded [F5Xe(FKrF)AsF6] and [F5Xe(FKrF)2AsF6], the first mixed krypton/xenon compounds. X‐ray crystal structures and Raman spectra show the KrF2 ligands and [AsF6]− anions are F‐coordinated to the xenon atoms of the [XeF5]+ cations. Quantum‐chemical calculations are consistent with essentially noncovalent ligand−xenon bonds that may be described in terms of σ‐hole bonding. These complexes significantly extend the XeF2–KrF2 analogy and the limited chemistry of krypton by introducing a new class of coordination compound in which KrF2 functions as a ligand that coordinates to xenon(VI). The HF solvates, [F5Xe(FH)AsF6] and [F5Xe(FH)SbF6], are also characterized in this study and they provide rare examples of HF coordinated to xenon(VI). [ABSTRACT FROM AUTHOR]

Fluorine‐based chemistry is widely used in commercial battery technology, from primary batteries consisting of Li/CFx to binders for electrodes in secondary lithium‐ion batteries. Fluorine‐based compounds are also formed during operation for both battery configurations as discharge products such as LiF or as components of the solid electrolyte interface (SEI) layers on electrodes. Herein, the fluorinated carbons or CFx detailing the commercialization of the first Li/CFx cells are discussed‐ the understanding of how performance is correlated to composition or x, the various methods to synthesize CFx compounds, the correlation between the nature of the CF bonds and electrochemical performance, the role of theoretical studies in such endeavors, the use of CFx in alternative battery chemistries and the wide range of techniques available to probe either CFx compounds individually or CFx compounds in devices under electrochemical conditions. A picture of the field from which future directions can be derived is provided. [ABSTRACT FROM AUTHOR]

Difluorochloronium(III) compounds were synthesized from the reaction of metal powders (Ru, Os, Ir, Au), metal fluorides (NbF5, SbF3, BiF5) or a metal chloride (TaCl5) with excess liquid chlorine trifluoride. The compounds ClF2[AuF4], ClF2[MF6] (M = Nb, Ta, Ru, Os, Ir, Sb, Bi) and ClF2[Ta2F11] were obtained in crystalline form and their crystal structures were determined by single‐crystal X‐ray diffraction. The ClF2+ cations in the investigated compounds are bent, containing two strong, short, mainly covalent Cl–F bonds and two sterically active, free valence electron pairs in a pseudo‐tetrahedral arrangement. The coordination around the Cl atom is extended by two highly ionic, long fluorine bridges to neighboring fluoridometallate anions, resulting in a total coordination number of six. The crystal structures vary among the ClF2+ compounds and range from molecular building blocks, such as dimeric (ClF2[AuF4])2 and (ClF2[Ta2F11])2, to chains, some of which being helical, as in ClF2[MF6], (M = Nb, Ta, Ru, Os, Ir, Sb, Bi). Quantum‐chemical solid‐state and gas‐phase calculations were carried out to elucidate the bonding within the ClF2+ cations and their interactions with the bridging F atoms. [ABSTRACT FROM AUTHOR]

This paper was written on the occasion of the 30th special Jubilee volume of Structural Chemistry journal in 2019. It offered us a unique opportunity to look at our common papers and achievements in the fields of thermochemistry and analytical chemistry with a special emphasis on fluorine-containing species. We have managed to build some new bridges between theory and experiment, and we look forward to building many more. [ABSTRACT FROM AUTHOR]

The TeF5 group is significantly underexplored as a highly fluorinated substituent on an organic framework, despite it being a larger congener of the acclaimed SF5 group. In fact, only one aryl‐TeF5 compound (phenyl‐TeF5) has been reported to date, synthesized using XeF2. Our recently developed mild TCICA/KF approach to oxidative fluorination provides an affordable and scalable alternative to XeF2. Using this method, we report a scope of extensively characterized aryl‐TeF5 compounds, along with the first SC‐XRD data on this compound class. The methodology was also extended to the synthesis and structural study of heretofore unknown aryl‐TeF4CF3 compounds. Additionally, preliminary reactivity studies unveiled some inconsistencies with previous literature regarding phenyl‐TeF5. Although our studies conclude that the arene‐based TeF5 (and TeF4CF3) group is not quite as robust as the SF5 group, we find that the TeF5 group is more stable than previously thought, thus opening a door to explore new applications of this motif. [ABSTRACT FROM AUTHOR]

A new chloronium‐containing salt, [Me2Cl][Al(OTeF5)4], was synthesized on multigram scale by means of a simple one‐pot procedure. The isolated product can be handled at room temperature and used as a strong electrophilic methylation agent. This is demonstrated by the methylation of the very weak bases P(CF3)3, PF3, MeI, and MeBr. [ABSTRACT FROM AUTHOR]

We report on the solid‐state structures of bis(nonafluoro‐tert‐butyl) peroxide [(F3C)3CO]2 and bis(undecafluoro‐2‐methyl‐2‐butyl) peroxide [(C2F5)(F3C)2CO]2. These peroxides were prepared from the corresponding hypofluorites and fluorinated silver wool. The solid‐state structures obtained after in situ crystallisation show unusual COOC dihedral angles of 180°, as well as elongated O−O bonds because of the bulky perfluorinated alkyl groups. The perfluorinated alkyl peroxides are insensitive to both impact (>40 J) and friction (>360 N), and resistant towards mineral acids (HX; X=F, Cl, Br) and elemental halogens (X2). Ferrocene is oxidized by [(F3C)3CO]2 to [FeIIICp2][OC(CF3)3]. Stretched planar peroxides: [(F3C)3CO]2 and [(C2F5)(F3C)2CO]2 were prepared from the corresponding hypofluorites and fluorinated silver wool. The solid‐state structures obtained after in situ crystallisation show unusual COOC dihedral angles of 180° as well as elongated O−O bonds because of the bulky perfluorinated alkyl groups. In addition, they are insensitive to both impact (>40 J) and friction (>360 N). [ABSTRACT FROM AUTHOR]

The pentafluoroorthotellurate (F5TeO–, teflato) group was transferred to two organonickel precursors resulting in the formation of [Ni(Hacac)2(OTeF5)2] and [Ni(iPrIm)2(OTeF5)2]. These complexes show completely different behavior in their stability against stronger coordinating agents, coordination arrangement, and their spin state. Interestingly, traces of water did not hydrolyze the teflato ligand, instead coordinating to the central nickel atom with formation of a dinuclear complex [{Ni(Hacac)(H2O)(OTeF5)(μ‐OTeF5)}2]. [ABSTRACT FROM AUTHOR]

Abstract: Because of the beneficial effect of a trifluoromethyl group on the biological properties of bioactive compounds on the one hand and the versatile synthetic potential of β-lactams on the other hand, 4-CF3-β-lactams comprises interesting entities for the preparation of a large variety of CF3-substituted nitrogen-containing target structures with promising biological characteristics. In this review, we present an overview of different building block approach-based routes toward the synthesis of 4-(trifluoromethyl)azetidin-2-ones and the application of the “β-lactam synthon method” for the synthesis of a diverse set of (a)cyclic CF3-substituted molecules by means of ring-opening and ring-transformation reactions.Graphical abstract: [ABSTRACT FROM AUTHOR]

α,α-Difluoro-benzyl phosphonates are currently the most popular class of phosphotyrosine mimetics. Structurally derived from the natural substrate phosphotyrosine, they constitute classical bioisosteres and have enabled the development of potent inhibitors of protein tyrosine phosphatases (PTP) and phosphotyrosine recognition sites such as SH2 domains. Being dianions bearing two negative charges, phosphonates, however, do not permeate membranes and thus are often inactive in cells and have not been a successful starting point toward therapeutics, yet. In this work, benzyl phosphonates were modified by replacing phosphorus-bound oxygen atoms with phosphorus-bound fluorine atoms. Surprisingly, mono- P-fluorophosphonates were fully stable under physiological conditions, thus enabling the investigation of their mode of action toward PTP. Three alternative scenarios were tested and mono- P-fluorophosphonates were identified as stable reversible PTP1B inhibitors, despite of the loss of one negative charge and the replacement of one oxygen atom as an H-bond donor by fluorine. In extending this replacement strategy, α,α-difluorobenzyl penta- P-fluorophosphates were synthesized and found to be novel phosphotyrosine mimetics with improved affinity to the phosphotyrosine binding site of PTP1B. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis and comprehensive characterization of tetrakis(pentafluoroethyl)germane. In addition to a complete NMR spectroscopic characterization, including the rarely used 73Ge NMR spectroscopy, Ge(C2F5)4 was studied by IR spectroscopy, mass spectrometry as well as X-ray diffraction analysis. A 73Ge NMR investigation as well as an X-ray diffraction study of the related germane Ge(CF3)4 are also included. [ABSTRACT FROM AUTHOR]

Molecular alkali tetrafluorido aurate ion pairs M[AuF4] (M=K, Rb, Cs) are produced by co‐deposition of IR laser‐ablated AuF3 and MF in solid neon under cryogenic conditions. This method also yields molecular AuF3 and its dimer Au2F6. The products are characterized by their Au–F stretching bands and high‐level quantum‐chemical calculations at the CCSD(T)/triple‐ζ level of theory. Structural changes in AuF4− associated with the coordination of the anion to different alkali cations are proven spectroscopically and discussed. [ABSTRACT FROM AUTHOR]

The potent oxidizer and highly shock-sensitive binary noble-gas oxide XeO3 interacts with CH3CN and CH3CH2CN to form O3XeNCCH3, O3Xe(NCCH3)2, O3XeNCCH2CH3, and O3Xe(NCCH2CH3)2. Their low-temperature single-crystal X-ray structures show that the xenon atoms are consistently coordinated to three donor atoms, which results in pseudo-octahedral environments around the xenon atoms. The adduct series provides the first examples of a neutral xenon oxide bound to nitrogen bases. Raman frequency shifts and Xe−N bond lengths are consistent with complex formation. Energy-minimized gas-phase geometries and vibrational frequencies were obtained for the model compounds O3Xe(NCCH3) n ( n=1-3) and O3Xe(NCCH3) n⋅[O3Xe(NCCH3)2]2 ( n=1, 2). Natural bond orbital (NBO), quantum theory of atoms in molecules (QTAIM), electron localization function (ELF), and molecular electrostatic potential surface (MEPS) analyses were carried out to further probe the nature of the bonding in these adducts. [ABSTRACT FROM AUTHOR]

Acetonitrile and [FXeOXe- - -FXeF][AsF6] react at −60 °C in anhydrous HF (aHF) to form the CH3CN adduct of the previously unknown [XeOXe]2+ cation. The low-temperature X-ray structure of [CH3CN- - -XeOXe- - -NCCH3][AsF6]2 exhibits a well-isolated adduct-cation that has among the shortest Xe−N distances obtained for an sp-hybridized nitrogen base adducted to xenon. The Raman spectrum was fully assigned by comparison with the calculated vibrational frequencies and with the aid of 18O-enrichment studies. Natural bond orbital (NBO), atoms in molecules (AIM), electron localization function (ELF), and molecular electrostatic potential surface (MEPS) analyses show that the Xe−O bonds are semi-ionic whereas the Xe−N bonds may be described as strong electrostatic (σ-hole) interactions. [ABSTRACT FROM AUTHOR]

Acetonitrile and the potent oxidative fluorinating agent XeF6 react at -40 °C in Freon-114 to form the highly energetic, shock-sensitive compounds F6XeNCCH3 (1) and F6Xe(NCCH3)2⋅CH3CN (2 ⋅CH3CN). Their low-temperature single-crystal X-ray structures show that the adducted XeF6 molecules of these compounds are the most isolated XeF6 moieties thus far encountered in the solid state and also provide the first examples of XeVI N bonds. The geometry of the XeF6 moiety in 1 is nearly identical to the calculated distorted octahedral (C3v) geometry of gas-phase XeF6. The C2v geometry of the XeF6moiety in 2 resembles the transition state proposed to account for the fluxionality of gas-phase XeF6. The energy-minimized gas-phase geometries and vibrational frequencies were calculated for 1 and 2, and their respective binding energies with CH3CN were determined. The Raman spectra of 1 and 2⋅CH3CN were assigned by comparison with their calculated vibrational frequencies and intensities. [ABSTRACT FROM AUTHOR]

Acetonitrile and the potent oxidative fluorinating agent XeF6 react at -40°C in Freon-114 to form the highly energetic, shock-sensitive compounds F6XeNCCH3 (1) and F6Xe(NCCH3)2-CH3CN (2-CH3CN). Their low-temperature single-crystal X-ray structures show that the adducted XeF6 molecules of these compounds are the most isolated XeF6 moieties thus far encountered in the solid state and also provide the first examples of XeVI-N bonds. The geometry of the XeF6 moiety in 1 is nearly identical to the calculated distorted octahedral (C3v) geometry of gas-phase XeF6. The C2v geometry of the XeF6 moiety in 2 resembles the transition state proposed to account for the fluxionality of gas-phase XeF6. The energy-minimized gas-phase geometries and vibrational frequencies were calculated for 1 and 2, and their respective binding energies with CH3CN were determined. The Raman spectra of 1 and 2-CH3CN were assigned by comparison with their calculated vibrational frequencies and intensities. [ABSTRACT FROM AUTHOR]

Building on our recent disclosure of catalysis at dinuclear PdI sites, we herein report the application of this concept to the realization of the first catalytic method to convert aryl iodides into the corresponding ArSeCF3 compounds. Highly efficient CSeCF3 coupling of a range of aryl iodides was achieved, enabled by an air-, moisture-, and thermally stable dinuclear PdI catalyst. The novel SeCF3-bridged dinuclear PdI complex 3 was isolated, studied for its catalytic competence and shown to be recoverable. Experimental and computational data are presented in support of dinuclear PdI catalysis. [ABSTRACT FROM AUTHOR]

New liquid crystals with very low viscosity, good mesophase behavior, and high reliability are necessary to achieve the breakthrough from flat computer monitors to large displays for television. Fluorine plays a decisive role not only because of the polarity it induces in organic molecules but also because of its low polarizability and weak propensity for ion solvation. In addition, subtle stereoelectronic effects in fluorine-containing liquid crystals influence material properties and allow these to be tuned to some extent to achieve the desired outcome. Some fairly sophisticated chemistry is required that is normally ruled out in the specialty chemicals industry because of cost. The television display market is now entering a phase of saturation. The broad availability of the internet has led to an ever increasing tendency for mobile products. Tablet PCs and smartphones require touch-panel functionality and low power consumption. New LCD modes with high-performance liquid crystals and additional components, such as polymerizable materials, can be used in such products. [ABSTRACT FROM AUTHOR]

The activation and functionalization of carbon-fluorine bonds can be considered as a major challenge in organometallic chemistry. The growing demand for means to introduce fluorine into new materials or into biologically active molecules has inspired the development of diverse synthetic strategies. Hydrodefluorination is regarded as a promising approach to access partially fluorinated building blocks from readily available perfluorinated bulk chemicals. We provide an overview of transition-metal-based complexes and catalysts that were developed to mediate hydrodefluorination reactions. Special emphasis will be placed on discussing the underlying mechanistic patterns and their impact on scope and selectivity. In addition, future requirements for further developing this field will be highlighted. [ABSTRACT FROM AUTHOR]

We report on Si nanopatterning through an on-chip self-assembled porous anodic alumina (PAA) masking layer using reactive ion etching based on fluorine chemistry. Three different gases/gas mixtures were investigated: pure SF6, SF6/O2, and SF6/CHF3. For the first time, a systematic investigation of the etch rate and process anisotropy was performed. It was found that in all cases, the etch rate through the PAA mask was 2 to 3 times lower than that on non-masked areas. With SF6, the etching process is, as expected, isotropic. By the addition of O2, the etch rate does not significantly change, while anisotropy is slightly improved. The lowest etch rate and the best anisotropy were obtained with the SF6/CHF3 gas mixture. The pattern of the hexagonally arranged pores of the alumina film is, in this case, perfectly transferred to the Si surface. This is possible both on large areas and on restricted pre-defined areas on the Si wafer. [ABSTRACT FROM AUTHOR]

A series of benzofused sultams and fluorinated benzenesulfonamides were synthesized in superacid HF/SbF5 from simple N-allylic derivatives. Almost all of these original compounds showed micromolar inhibitory activities against carbonic anhydrases I and II. The fluorinated derivatives inhibit better the tumor-associated isoforms IX and XII, and one of the tested compounds showed inhibition in the nanomolar range. [ABSTRACT FROM AUTHOR]

Adsorption, Fluorine chemistry, Materials, Porous organic cages, Supramolecular chemistry Porous organic cage compounds with their discrete nanocavities have emerged as a versatile functional-materials platform and we highlight examples of porous organic cages with focus on how the intrinsic nanopore can be controlled and utilized, in addition to the synthesis and the gas sorption properties of smaller intrinsic pores of porous organic cage compounds, porous macrocycles and other related compounds. Keywords: Adsorption; Fluorine chemistry; Materials; Porous organic cages; Supramolecular chemistry EN Adsorption Fluorine chemistry Materials Porous organic cages Supramolecular chemistry 5843 5843 1 11/24/21 20211122 NES 211122 B The Front Cover b shows the diverse library of porous organic compounds, designed and synthesized by scientists working in the field featured in our review article. [Extracted from the article]

Cage compounds, crystal structures, dynamic covalent chemistry, fluorine chemistry, materials Keywords: cage compounds; crystal structures; dynamic covalent chemistry; fluorine chemistry; materials EN cage compounds crystal structures dynamic covalent chemistry fluorine chemistry materials 8409 8409 1 06/12/21 20210610 NES 210610 B Eight hybrid Tri SP 4 sp Di SP 6 sp imine cages b with a tuneable degree of fluorination and one fully fluorinated Tri SP 4 sp Di SP 6 sp imine cage are formed by [4+6] dynamic imine condensation in solution. [Extracted from the article]

SiF was added into SiH-H to deposit polycrystalline silicon films at low temperatures around 400°C in a remote plasma enhanced chemical vapor deposition reactor. It was found out that the fluorine chemistry obtained from SiF addition had an influence on the chemical composition, crystallinity, and silicon dangling bond density of the film. The fluorine chemistry reduced the amount of hydrogen and oxygen incorporated into the film and also suppressed the formation of powders in the gas phase, which helped the crystallization at low temperatures. Effect of SiF concentration as well as the deposition temperature was also significant. [ABSTRACT FROM AUTHOR]