Review
Chemistry, Multidisciplinary
Shyam Basak, Laura Winfrey, Betty A. Kustiana, Rebecca L. Melen, Louis C. Morrill, Alexander P. Pulis
Summary: Boranes have the ability to mediate hydride abstraction from amino C-H bonds, resulting in the generation of reactive iminium hydridoborate salts that can participate in various stoichiometric and catalytic processes. These reactions include manipulation of amino scaffolds and the use of amine-based reagents for reactions such as transfer hydrogenation and alkylation.
CHEMICAL SOCIETY REVIEWS
(2021)
Article
Chemistry, Organic
Joseph P. Gillions, Salma A. Elsherbeni, Laura Winfrey, Lei Yun, Rebecca L. Melen, Louis C. Morrill, Alexander P. Pulis
Summary: C-H functionalization is an important area in synthetic methodology, and electron-deficient organoboranes have great potential in mediating hydride abstraction from alpha-amino C-H bonds. This review covers recent advances in organoborane-mediated hydride abstraction, focusing on their catalytic applications in alpha- or beta-functionalization, alpha,beta-difunctionalization, and amine dehydrogenation.
Article
Chemistry, Organic
Xia Zhao, Wen-Yan Tong, Xiaotai Wang
Summary: This study investigates the detailed workings of copper-catalyzed hydroarylation of alkenes with polyfluoroarenes, focusing on C-F bond functionalization. The results show that the regioselectivity of the reaction is influenced by a combination of orbital and dispersion interactions induced by the aryl alkene substrate. The mechanistic insights obtained from this study can have significant implications for the development of new transition metal-catalyzed hydroarylation and C-F functionalization reactions.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Xia Zhao, Wen-Yan Tong, Xiaotai Wang
Summary: This study investigates the detailed mechanism of CuH-catalyzed hydroarylation of alkenes with polyfluoroarenes involving C-F bond functionalization. The research reveals that the regioselectivity is determined by a combination of orbital and dispersion interactions induced by the aryl alkene substrate. Additionally, the benzyl ligand facilitates a cupratropic shift, allowing for nucleophilic aromatic substitution. Noncovalent interactions play a crucial role in the regioselectivity of C-F bond cleavage.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Jaume Rostoll-Berenguer, Maria Martin-Lopez, Gonzalo Blay, Jose R. Pedro, Carlos Vila
Summary: In this study, a visible-light photocatalytic radical addition reaction of dihydroquinoxalin-2-ones to trifluoromethyl ketones has been established using Ru(bpy)3Cl2 as a photocatalyst and HP Single Blue LED as the light source. The reaction allows for the synthesis of dihydroquinoxalin-2-ones bearing a trifluoromethyl-substituted tertiary alcohol moiety in moderate to good yields under mild conditions.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Guangshou Feng, Colton K. Ku, Jiaqi Zhao, Qiu Wang
Summary: This paper reports an unprecedented three-component aminofluorination of alkenes and 1,3-dienes, which can achieve the synthesis of fi-fluoroalkylamines using innovative copper-catalyzed electrophilic amination strategy and alkylamine precursors. The method features high regioselectivity and good tolerance of various functional groups, providing a direct entry to a broad range of fi-fluorinated alkylamines.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Organic
Zhongxue Fang, Yanmei Gong, Binbin Liu, Jin Zhang, Xinyue Han, Zhaohong Liu, Yongquan Ning
Summary: Herein, we report the pioneering Rh-catalyzed coupling reactions between a fluoroalkyl carbene and azides to access alpha-trifluoroethylated imines. Through the use of fluoroalkyl N-sulfonylhydrazones as fluoroalkyl diazo surrogates, two C-N bond formation products were obtained using TMSN3 as the N source. Additionally, the alpha-trifluoroethylated imine products were easily reduced to the corresponding N-trifluoroethylated anilines. Experimental results and theoretical calculations support a stepwise reaction pathway involving the formation of rhodium carbene, the addition of HN3, and C=N bond formation.
Article
Chemistry, Organic
Fengyun Gao, Yifei Guo, Mengmeng Sun, Yalan Wang, Changyan Yang, Yuqiang Wang, Kairong Wang, Wenjin Yan
Summary: A novel difluoromethylated ketimine building block was synthesized for the first time by condensation of thioisatin and difluoroethylamine, providing efficient access to enantioenriched products with difluoroethylamine units. Further transformation of the intermediate led to the generation of versatile functional blocks while retaining the enantiomeric excess at the difluoromethyl-bound carbon.
Article
Chemistry, Multidisciplinary
Daisuke Uraguchi, Kohsuke Kato, Takashi Ooi
Summary: An o-quinone methide (o-QM) with an overcrowded olefinic framework is introduced, showing dehydridation activity due to its enhanced zwitterionic character, especially under photoexcitation. Experimental analysis and density functional theory calculations provide mechanistic insights, revealing that the o-QM operates in dehydridative catalysis for the oxidation of benzylic secondary alcohols.
Article
Chemistry, Physical
Praphatsorn Plerdsranoy, Palmarin Dansirima, Torben R. Jensen, Rapee Utke
Summary: This study proposes the improvement of de/rehydrogenation kinetics and reversibility of the LiNH2-LiH system by substituting F for H in LiNH2. By combining LiNH2 with excess LiH and compaction, NH3 emission and degradation of hydrogen capacity can be prevented. The formation of LiNH(2-x)Fx achieved from F substitution significantly enhances kinetic properties, and good kinetics and reversibility are preserved even after multiple de/absorption cycles.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Multidisciplinary
Suguru Yoshida
Summary: We have developed selective methods for single C-F transformations of aromatic trifluoromethyl compounds, enabling us to prepare a broad range of organofluorines from simple benzotrifluorides through C-F and C-Si transformations. These methods include allylation using trityl cations, thiolation and azidation catalyzed by Yb(OTf)(3), as well as chlorination using trityl chloride. The resulting fluorosilyl group in these transformations can undergo further reactions such as protonation, halogenation, and Hiyama cross-coupling with C-Si cleavage. Additionally, benzyl fluorides can be synthesized through LiAlH4-reduction of the resulting fluorosilanes and further C-F transformations.
Article
Chemistry, Multidisciplinary
Pierre Fosse, Emmanuel Pfund, Thierry Lequeux
Summary: The synthesis of undescribed β-aminodifluoroethylsulfinates and their uses in the hydroaminodifluoroalkylation of alkenes were reported. This reaction was performed in the presence of a photocatalyst (4CzIPN, Ru complexes) and enabled the direct incorporation of a β-difluoroamine moiety into vinylic aryls, unactivated alkenes, and electron-rich or -deficient alkenes. The mechanism was studied, and the formation of a gem-difluoromethyl radical was observed after the selective oxidation of the sulfinate function.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Review
Chemistry, Multidisciplinary
Solene Morand, Philippe Jubault, Jean-Philippe Bouillon, Samuel Couve-Bonnaire
Summary: This review presents an overview of the syntheses of gem-heteroatom-substituted fluoroalkenes over the past decade, covering various common heteroatoms and their potential applications in mimicking important organic functions.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Jannik Gilmer, Michael Bolte, Alexander Virovets, Hans-Wolfram Lerner, Felipe Fantuzzi, Matthias Wagner
Summary: This study investigates the B-nucleophilic reaction and its mechanism. It is found that the reaction between B-nucleophilic 9H-9-borafluorene dianion and 9-chloro-9-silafluorene leads to the formation of silylborate salts, which further react with pyridine or chlorosilane to give different products. The proposed reaction mechanism is supported by DFT calculations. Moreover, the treatment of the resulting products with N-heterocyclic carbene IMe leads to the formation of silylene.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Richa Gupta, Dipendu Mandal, Amit K. Jaiswal, Rowan D. Young
Summary: This study presents a frustrated Lewis pair (FLP)-catalyzed monoselective C-F activation method for a range of aliphatic polyfluorocarbons with equivalent geminal and distal C-F positions, which can be further functionalized through various reactions.
Article
Chemistry, Multidisciplinary
Robin F. Weitkamp, Beate Neumann, Hans-Georg Stammler, Berthold Hoge
Summary: Deprotonation of phenol derivatives using tetraphosphazene bases allows for the preparation of salts with free phenolate anions and enables the selective synthesis of hydrogen bonded phenol-phenolate salts. This work demonstrates the capability of a phosphazenium phenolate salt to selectively activate the chemically inert greenhouse gas SF6 through a two-electron reduction process, resulting in the formation of phosphazenium pentafluorosulfanide ([SF5](-)) and fluoride salts.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Inorganic & Nuclear
Mira Kessler, Sven Porath, Hans-Georg Stammler, Berthold Hoge
Summary: The paper investigates the molecular structure of trimethylsilanes Si(CH3)(3)X with different substituents X and their electron withdrawing effects. It is found that the lengths of Si-C bonds are influenced by orbital hybridization and steric demand rather than electron withdrawing capability. Additionally, a method for generating trifluoropropyn-1-yllithium from HFO-1234yf and n-butyllithium is presented.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Natalia Tiessen, Mira Kessler, Beate Neumann, Hans-Georg Stammler, Berthold Hoge
Summary: The research findings suggest that the electronic structure of perfluoroalkylated silanides leads to their behavior as either a Lewis base or a Lewis amphoteric substance similar to silylenes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Natalia Tiessen, Nico Schwarze, Mira Kessler, Beate Neumann, Hans-Georg Stammler, Berthold Hoge
Summary: This study focused on investigating the Lewis amphoteric behavior of perfluoroalkyl siloxanes and their congener species, revealing the strong electron-withdrawing properties of pentafluoroethyl substituents. The synthesis of corresponding silanol and characterization of dimeric triorganosilanolate provided evidence for the Lewis amphoteric character of the monomeric anion.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Review
Chemistry, Multidisciplinary
Robin F. Weitkamp, Beate Neumann, Hans-Georg Stammler, Berthold Hoge
Summary: The renaissance of Bronsted superbases is based on their ability to undergo various chemical transformations under mild conditions. Four major factors can be adjusted to tune their basicity selectively, including the nature of the basic center, electron donation by substituents, charge delocalization, and energy gain by hydrogen bonding. The appearance of neutral electron-rich phosphine and phosphazene bases in literature over the past decades has made them indispensable as auxiliary bases in deprotonation processes. Their applications in catalysis and coordination chemistry have also gained widespread interest.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Natalia Tiessen, Mira Kessler, Beate Neumann, Hans-Georg Stammler, Berthold Hoge
Summary: This paper introduces an anion based on Group 14 element that is capable of oxidative additions towards C-F bonds, leading to the isolation of non-chelated tetraorganofluorosilicate salts.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Oleg O. Shyshkov, Alexander A. Kolomeitsev, Berthold Hoge, Enno Lork, Axel Haupt, Mira Kessler, Gerd-Volker Roeschenthaler
Summary: Phosphoranides are hypervalent species that can serve as model compounds for intermediates or transition states in nucleophilic substitution reactions. This study reports the syntheses and properties of stable trifluoromethylphosphoranide salts, and investigates their reactivity towards electrophiles. The structures and dynamics of these compounds are determined using X-ray crystallography and NMR spectroscopy.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Inorganic & Nuclear
Natalia Tiessen, Nico Schwarze, Hans-Georg Stammler, Beate Neumann, Berthold Hoge
Summary: A convenient synthesis method for tris(pentafluoroethyl)silylchalcogenolate salts was presented and fully characterized. The reactivity of these species towards selected metal halide complexes was investigated for the first time, leading to the isolation and characterization of metal complexes.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Inorganic & Nuclear
Mira Kessler, Hans-Georg Stammler, Beate Neumann, Gerd-Volker Roeschenthaler, Berthold Hoge
Summary: By replacing two fluorine atoms with electron withdrawing pentafluoroethyl groups in metal tetrafluorophosphanides, the stability of these compounds was enhanced and various silver complexes were synthesized, including the first homoleptic phosphoranidometal complex with an [AgX3](2-) ion structural motif.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Inorganic & Nuclear
Mira Kessler, Lukas Hartmann, Hans-Georg Stammler, Beate Neumann, Gerd-Volker Roeschenthaler, Berthold Hoge
Summary: In this study, the free [P(C2F5)2F(2)]- ion and its ligand properties in transition metal complex chemistry are investigated. The transfer effects and fluorinating abilities of the ion on other metal complexes are explored.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Sven Porath, Mira Kessler, Beate Neumann, Hans-Georg Stammler, Berthold Hoge
Summary: In this study, the synthesis method of a novel tetrakis(pentafluoroethyl)indate and its characteristics in different cations were reported. These indates are the first isolated perfluoroalkylindium compounds that are fully characterized by NMR spectroscopy, mass spectrometry, elemental analysis, and X-ray diffraction analysis.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Polymer Science
Christian Alter, Robin F. Weitkamp, Berthold Hoge
Summary: Novel acrylate polymers functionalized with tetrafluorophenyl phosphonic acid groups were synthesized. The free acid functions were liberated through ester cleavage and subsequent hydrolysis. The obtained polymers were characterized by NMR and IR spectroscopy. The ion exchange capacity and proton conductivity were determined to be 2.8 mmol/g and 6.84 x 10(-6) Scm(-1) at 120 degrees C, respectively.
JOURNAL OF APPLIED POLYMER SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Mira Kessler, Michael Kapiza, Stammler Hans-Georg, Beate Neumann, Roeschenthaler Gerd-Volker, Berthold Hoge
Summary: Phosphoranides with three phosphorus carbon bonds are rare in the literature. We synthesized these compounds using tris(pentafluoroethyl)phosphane, P(C2F5)(3), and cyanobis(pentafluoroethyl)phosphane, P(C2F5)(2)(CN), with electron withdrawing pentafluoroethyl groups. Metal fluorides MF (M=Ag, Cs) add to P(C2F5)(3) to yield M[P(C2F5)(3)F] salts, which subsequently undergo C2F4 loss to form M[P(C2F5)(2)F-2]. The cesium salt decomposes quickly at room temperature, while the silver salt decomposes slowly over several days. Ag[P(C2F5)(3)F] reacts with 2,2'-bipyridine to give [Ag(bipy){P(C2F5)(3)F}] for structural characterization. With P(C2F5)(2)(CN), AgF substitutes the cyano group instead of forming phosphoranides. However, [K(18-crown-6)]F adds to P(C2F5)(2)(CN) to yield [K(18-crown-6)][P(C2F5)(2)(CN)F], which can undergo substituent exchange to form [K(18-crown-6)][P(C2F5)(2)F-2] and possibly [K(18-crown-6)][P(C2F5)(2)(CN)(2)]. The equilibrium between the latter and [K(18-crown-6)]CN and P(C2F5)(2)(CN) favors the phosphane and cyanide salt.
Article
Chemistry, Physical
Lukas Eickhoff, Mira Kessler, Christopher Stubbs, Jakob Derksen, Martina Viefhues, Dario Anselmetti, Matthew I. I. Gibson, Berthold Hoge, Thomas Koop
Summary: This study explores the relationship between the molecular size of poly(vinyl alcohol) (PVA) and its ice nucleation activity. The experiments show that the ice nucleation activity of shorter PVA chains significantly decreases with a decrease in molar mass. The results support the view that PVA polymers and oligomers act as heterogeneous ice nucleators.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Inorganic & Nuclear
Mira Kessler, Lukas Hartmann, Hans-Georg Stammler, Beate Neumann, Gerd-Volker Roeschenthaler, Berthold Hoge
Summary: This contribution focuses on the free [P(C2F5)2F(2)]- ion and its ligand properties in transition metal complex chemistry. The weak interaction between the cation and anion allows the ion to meet pseudo-gas-phase conditions. Efficient transfer of the P(C2F5)2F(2) moiety is demonstrated through ligand substitution and transmetalation reactions.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Xianda Wu, Minghong Chen, Shuiyun Zheng, Fu-Sheng He, Jie Wu
Summary: Here, we report a new method for synthesizing sulfilimines through an iron-catalyzed reaction between sulfenamides and 2,2,2-trifluor-diazoethane. This protocol features operational simplicity, mild conditions, and can be conducted in open air, providing a facile approach to trifloromethylated sulfilimines in moderate to good yields.
JOURNAL OF FLUORINE CHEMISTRY
(2024)
Article
Chemistry, Inorganic & Nuclear
Ita Hajdin, Romana Pajkert, Haibo Mei, Jianlin Han, Gerd-Volker Roeschenthaler
Summary: A catalyst- and solvent-free 1,3-dipolar cycloaddition reaction using a bench-stable diazo reagent has been developed to obtain a series of novel 3H-pyrazoles bearing difluoromethyl phosphonate unit in moderate-to-excellent yields. This method provides an efficient and easy route to synthesize valuable compounds.
JOURNAL OF FLUORINE CHEMISTRY
(2024)
