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The alkylation of 3‐/4‐bromo‐ and ‐iodopyridine with methyl triflate smoothly affords the corresponding N‐methylpyridinium triflate salts. An anion exchange with NaI or [PPh4]Y (Y=Cl, Br, I) yields the corresponding halide salts. Most of them could be structurally characterized and their strong halogen bonds were investigated. While the halogen atom of 4‐halogenopyridinium is susceptible to nucleophilic substitution, 3‐halogenopyridinium ions are far more stable against nucleophilic attacks. Due to the comparable interaction strength of halogen bonds and hydrogen bonds, the latter of which is widely used in chromatography, the potential of 3‐halogenopyridinium moieties for an application in chromatography is obvious and was successfully employed in affinity chromatography of different proteins. [ABSTRACT FROM AUTHOR]

The reaction of [Ga(C2F5)3(FSiMe3)] with chlorotrimethylsilane leads to the selective substitution of the α‐fluorine atoms by chlorine atoms and thus to the formation of [Ga(CCl2CF3)3(FSiMe3)]. The corresponding chlorogallate ion, [Ga(CCl2CF3)3Cl]−, could be isolated and structurally characterized as its tetraphenylphosphonium salt. The catalytic potential of [Ga(CCl2CF3)3(FSiMe3)] was demonstrated via the chlorodefluorination of Me3SiCF3, 2,2‐difluoropropane and [PPh4][Ga(C2F5)4]. [ABSTRACT FROM AUTHOR]

Although the adduct of aluminum trichloride with thionyl chloride has been reported, no thionyl chloride adduct of a main group element Lewis acid or organometallic compound has been structurally characterized. In this communication we present the synthesis and reactivity of the structurally ascertained adduct of thionyl chloride with tris(pentafluoroethyl)gallane as a representative of a main group element Lewis acid. Gallium and indium compounds with electron withdrawing groups, e.g. the pentafluoroethyl ligand, display versatile properties. While gallates and indates, [MR4]−, behave as weakly coordinating anions, neutral gallanes and indanes, MR3, are strong Lewis acids. Salts with the tetrakis(pentafluoroethyl)gallate and ‐indate, [M(C2F5)4]− (M=Ga, In), have recently been studied in detail. In contrast to this, work on the syntheses of the free Lewis superacids M(C2F5)3 (M=Ga, In) is scarce and underdeveloped. The hydrates [M(C2F5)3(OH2)2] proved to be suitable starting materials, particularly due to their thermal stability. Herein we report on synthesis and characterization of reactive adducts, [M(C2F5)3D], with the weak donor molecules (D) SOCl2 and Me3SiF. The effective Lewis acidities of Ga(C2F5)3 and In(C2F5)3 were experimentally determined by the (modified) Gutmann‐Beckett method and their catalytic potential is showcased. [ABSTRACT FROM AUTHOR]

Bidentate and tetradentate chalcogen bonding host systems with SeCF3 functions as σ-hole donors in close proximity at the alkyne functions of 1,8-diethynylanthracene and its syn-dimer were prepared in quantitative yield by tin-selenium exchange reactions of the corresponding trimethylstannyl precursors with ClSeCF3. The bidentate system shows chalcogen bonding interactions with THF, but does not bind halide ions. The tetradentate system cooperatively chelates chloride, bromide and iodide ions with its four C≡C–SeCF3 units by rotating the four σ-holes towards the halide ion. The structures of these halide ion adducts were determined by X-ray diffraction. The hydrobromide and -iodide salts of the ethyl derivative of Schwesinger's phosphazene superbase served as halide salts with very weakly coordinating cations. [ABSTRACT FROM AUTHOR]

Poly(vinyl alcohol) (PVA) has ice binding and ice nucleating properties. Here, we explore the dependence of the molecular size of PVA on its ice nucleation activity. For this purpose, we studied ice nucleation in aqueous solutions of PVA samples with molar masses ranging from 370 to 145 000 g mol−1, with a particular focus on oligomer samples with low molar mass. The experiments employed a novel microfluidic setup that is a follow-up on the previous WeIzmann Supercooled Droplets Observation on a Microarray (WISDOM) design by Reicher et al. The modified setup introduced and characterized here, termed nanoliter Bielefeld Ice Nucleation ARraY (nanoBINARY), uses droplet microfluidics with droplets (96 ± 4) µm in diameter and a fluorinated continuous oil phase and surfactant. A comparison of homogeneous and heterogeneous ice nucleation data obtained with nanoBINARY to those obtained with WISDOM shows very good agreement, underpinning its ability to study low-temperature ice nucleators as well as homogeneous ice nucleation due to the low background of impurities. The experiments on aqueous PVA solutions revealed that the ice nucleation activity of shorter PVA chains strongly decreases with a decrease in molar mass. While the cumulative number of ice nucleating sites per mass nm of polymers with different molar masses is the same, it becomes smaller for oligomers and completely vanishes for dimer and monomer representatives such as 1,3-butanediol, propan-2-ol, and ethanol, most likely because these molecules become too small to effectively stabilize the critical ice embryo. Overall, our results are consistent with PVA polymers and oligomers acting as heterogeneous ice nucleators. [ABSTRACT FROM AUTHOR]

Tris(pentafluoroethyl)indane dihydrate, [In(C2F5)3(OH2)2], and the gallium analog, [Ga(C2F5)3(OH2)2], serve as transfer reagents for the In(C2F5)3 and Ga(C2F5)3 units, as illustrated by the preparation of salts of (pseudo)halogenotris(pentafluoroethyl)indate and ‐gallate anions, [M(C2F5)3)X]− (M=Ga, In; X=F, Cl, Br, I, CN, SCN). Due to the water tolerance and water solubility of [In(C2F5)3(OH2)2] and [Ga(C2F5)3(OH2)2], reactions can be performed in the presence of water or even in an aqueous medium. [ABSTRACT FROM AUTHOR]

The introduction of a number of unsaturated fluorinated and chlorinated substituents onto gallium and indium was investigated. Gallate, [GaR4]−, and indate, [InR4]−, anions with trifluorovinyl (CF=CF2), 1‐chloro‐2,2‐difluorovinyl (CCl=CF2), (E)‐pentafluoropropen‐1‐yl (E‐CF=CFCF3), 3,3,3‐trifluoropropynyl (C≡C−CF3) and dichloromethyl (CHCl2) substituents were synthesized and isolated as the respective tetraphenylphosphonium salts. The respective gallate and indate salts were characterized by various methods, including NMR spectroscopy, mass spectrometry and X‐ray diffraction analysis. The generation of the respective organyllithium reagents, required for the syntheses of the gallate and indates, was performed starting from commercially available materials. This series of novel gallate and indate salts extends the chemistry of electron withdrawing groups to gallium and indium compounds. [ABSTRACT FROM AUTHOR]

Novel acrylate polymers functionalized with tetrafluorophenyl phosphonic acid groups were prepared by free radical polymerization of phosphonic ester acrylate monomers. Liberation of the free acid functions was realized by ester cleavage with Me3SiBr and the subsequent hydrolysis with methanol. The obtained polymers were analyzed by NMR and IR spectroscopy. The ion exchange capacity of the phosphonic acid functionalized methacrylate polymer was determined to 2.8 mmol/g by titration with 0.1 M NaOH. The proton conductivity under anhydrous conditions was determined to 6.84 × 10−6 Scm−1 at 120°C by electrochemical impedance spectroscopy. [ABSTRACT FROM AUTHOR]

Compounds exhibiting main group elements in low oxidation states were found to mimic the reactivity of transition metal complexes. Like the latter, such main group species show a proclivity of changing their oxidation state as well as their coordination number by +2, therefore fulfilling the requirements for oxidative additions. Prominent examples of such main group compounds that undergo oxidative additions with organohalides R−X (R=alkyl, aryl, X=F, Cl, Br, I) are carbenes and their higher congeners. Aluminyl anions, which like carbenes and silylenes oxidatively add to strong σ‐bonds in R−X species, have been recently discovered. We present the first anion based upon a Group 14 element, namely the tris(pentafluoroethyl)silanide anion, [Si(C2F5)3]−, which is capable of oxidative additions towards C−F bonds. This enables the isolation of non‐chelated tetraorganofluorosilicate salts, which to the best of our knowledge had only been observed as reactive intermediates before. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Keywords: Anions; hypervalent compounds; P ligands; perfluoroalkyl groups; phosphoranides EN Anions hypervalent compounds P ligands perfluoroalkyl groups phosphoranides 1 1 1 07/28/23 20230701 NES 230701 B The cover image shows b two cyanofluorobis(pentafluoroethyl)phosphoranide anions, [P(C SB 2 sb F SB 5 sb ) SB 2 sb (CN)F] SP - sp , as spaceships. Anions, hypervalent compounds, P ligands, perfluoroalkyl groups, phosphoranides. [Extracted from the article]

Fluorine, Oxidative Addition, Perfluorosilicates, Silanide Anion, Silicon Frontispiece: Oxidative Additions of C-F Bonds to the Silanide Anion [Si(C2F5)3]- Keywords: Fluorine; Oxidative Addition; Perfluorosilicates; Silanide Anion; Silicon EN Fluorine Oxidative Addition Perfluorosilicates Silanide Anion Silicon 1 1 1 04/14/22 20220419 NES 220419 B Silicon b In their Research Article (e202116468), Berthold Hoge et al. report oxidative additions of [Si(C SB 2 sb F SB 5 sb ) SB 3 sb ] SP - sp to aryl- and alkenylfluorides, enabling the isolation of tetraorganofluorosilicate salts devoid of chelating ligands. [Extracted from the article]

Silicon In their Research Article (e202116468), Berthold Hoge et al. report oxidative additions of [Si(C2F5)3]− to aryl‐ and alkenylfluorides, enabling the isolation of tetraorganofluorosilicate salts devoid of chelating ligands. [ABSTRACT FROM AUTHOR]

Keywords: Fluor; Oxidative Addition; Perfluorosilicate; Silanid-Anion; Silicium DE Fluor Oxidative Addition Perfluorosilicate Silanid-Anion Silicium 1 1 1 04/12/22 20220419 NES 220419 B Silicium b In ihrem Forschungsartikel (e202116468) berichten Berthold Hoge et al. über oxidative Additionen von [Si(C SB 2 sb F SB 5 sb ) SB 3 sb ] SP - sp an Aryl- und Alkenylfluoride, welche die Isolierung von Tetraorganofluorosilicatsalzen frei von chelatisierende Liganden ermöglichen. Frontispiz: Oxidative Addition von C-F-Bindungen an das Silanid-Anion [Si(C2F5)3]-. [Extracted from the article]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Compounds exhibiting main group elements in low oxidation states were found to mimic the reactivity of transition metal complexes. Like the latter, such main group species show a proclivity of changing their oxidation state as well as their coordination number by +2, therefore fulfilling the requirements for oxidative additions. Prominent examples of such main group compounds that undergo oxidative additions with organohalides R−X (R=alkyl, aryl, X=F, Cl, Br, I) are carbenes and their higher congeners. Aluminyl anions, which like carbenes and silylenes oxidatively add to strong σ‐bonds in R−X species, have been recently discovered. We present the first anion based upon a Group 14 element, namely the tris(pentafluoroethyl)silanide anion, [Si(C2F5)3]−, which is capable of oxidative additions towards C−F bonds. This enables the isolation of non‐chelated tetraorganofluorosilicate salts, which to the best of our knowledge had only been observed as reactive intermediates before. [ABSTRACT FROM AUTHOR]

Verbindungen von Hauptgruppenelementen in niedrigen Oxidationsstufen sind in der Lage, die Reaktivität von Übergangsmetallkomplexen nachzuahmen. Wie Letztere neigen niedervalente Hauptgruppenelementverbindungen zur Änderung ihrer Oxidationsstufe und Koordinationszahl um +2, wodurch sie die wesentlichen Voraussetzungen für oxidative Additionen erfüllen. Prominente Beispiele für Hauptgruppenelementverbindungen, die mit Organohalogeniden R−X (R=Alkyl, Aryl, X=F, Cl, Br, I) oxidative Additionen eingehen, sind Carbene und ihre höheren Analoga. Kürzlich wurde auch über Aluminyl‐Anionen berichtet, die wie Carbene und Silylene starke σ‐Bindungen von R−X‐Spezies oxidativ addieren können. Hier stellen wir nun mit dem Tris(pentafluorethyl)silanid‐Anion, [Si(C2F5)3]−, das erste Anion aus der 14. Gruppe vor, welches C−F‐Bindungen im Sinne einer oxidativen Addition zu spalten vermag. Dies ermöglichte die Isolierung von nicht‐chelatierten Tetraorganofluorosilicat‐Salzen, die unseres Wissens bisher nur als reaktive Zwischenstufen nachgewiesen wurden. [ABSTRACT FROM AUTHOR]

Fluorine, Oxidative Addition, Perfluorosilicates, Silanide Anion, Silicon Frontispiece: Oxidative Additions of C-F Bonds to the Silanide Anion [Si(C2F5)3]- Keywords: Fluorine; Oxidative Addition; Perfluorosilicates; Silanide Anion; Silicon EN Fluorine Oxidative Addition Perfluorosilicates Silanide Anion Silicon 1 1 1 04/14/22 20220419 NES 220419 B Silicon b In their Research Article (e202116468), Berthold Hoge et al. report oxidative additions of [Si(C SB 2 sb F SB 5 sb ) SB 3 sb ] SP - sp to aryl- and alkenylfluorides, enabling the isolation of tetraorganofluorosilicate salts devoid of chelating ligands. [Extracted from the article]

Silicon In their Research Article (e202116468), Berthold Hoge et al. report oxidative additions of [Si(C2F5)3]− to aryl‐ and alkenylfluorides, enabling the isolation of tetraorganofluorosilicate salts devoid of chelating ligands. [ABSTRACT FROM AUTHOR]

Silicium In ihrem Forschungsartikel (e202116468) berichten Berthold Hoge et al. über oxidative Additionen von [Si(C2F5)3]− an Aryl‐ und Alkenylfluoride, welche die Isolierung von Tetraorganofluorosilicatsalzen frei von chelatisierende Liganden ermöglichen. [ABSTRACT FROM AUTHOR]

Keywords: Fluor; Oxidative Addition; Perfluorosilicate; Silanid-Anion; Silicium DE Fluor Oxidative Addition Perfluorosilicate Silanid-Anion Silicium 1 1 1 04/12/22 20220419 NES 220419 B Silicium b In ihrem Forschungsartikel (e202116468) berichten Berthold Hoge et al. über oxidative Additionen von [Si(C SB 2 sb F SB 5 sb ) SB 3 sb ] SP - sp an Aryl- und Alkenylfluoride, welche die Isolierung von Tetraorganofluorosilicatsalzen frei von chelatisierende Liganden ermöglichen. Frontispiz: Oxidative Addition von C-F-Bindungen an das Silanid-Anion [Si(C2F5)3]-. [Extracted from the article]

The alkylation of 3-/4-bromo- and -iodopyridine with methyl triflate smoothly affords the corresponding N-methylpyridinium triflate salts. An anion exchange with NaI or [PPh 4 ]Y (Y=Cl, Br, I) yields the corresponding halide salts. Most of them could be structurally characterized and their strong halogen bonds were investigated. While the halogen atom of 4-halogenopyridinium is susceptible to nucleophilic substitution, 3-halogenopyridinium ions are far more stable against nucleophilic attacks. Due to the comparable interaction strength of halogen bonds and hydrogen bonds, the latter of which is widely used in chromatography, the potential of 3-halogenopyridinium moieties for an application in chromatography is obvious and was successfully employed in affinity chromatography of different proteins., (© 2024 The Author(s). Chemistry - A European Journal published by Wiley-VCH GmbH.)

The reaction of [Ga(C 2 F 5 ) 3 (FSiMe 3 )] with chlorotrimethylsilane leads to the selective substitution of the α-fluorine atoms by chlorine atoms and thus to the formation of [Ga(CCl 2 CF 3 ) 3 (FSiMe 3 )]. The corresponding chlorogallate ion, [Ga(CCl 2 CF 3 ) 3 Cl] - , could be isolated and structurally characterized as its tetraphenylphosphonium salt. The catalytic potential of [Ga(CCl 2 CF 3 ) 3 (FSiMe 3 )] was demonstrated via the chlorodefluorination of Me 3 SiCF 3 , 2,2-difluoropropane and [PPh 4 ][Ga(C 2 F 5 ) 4 ]., (© 2024 The Author(s). Chemistry - A European Journal published by Wiley-VCH GmbH.)

Although the adduct of aluminum trichloride with thionyl chloride has been reported, no thionyl chloride adduct of a main group element Lewis acid or organometallic compound has been structurally characterized. In this communication we present the synthesis and reactivity of the structurally ascertained adduct of thionyl chloride with tris(pentafluoroethyl)gallane as a representative of a main group element Lewis acid. Gallium and indium compounds with electron withdrawing groups, e.g. the pentafluoroethyl ligand, display versatile properties. While gallates and indates, [MR 4 ] - , behave as weakly coordinating anions, neutral gallanes and indanes, MR 3 , are strong Lewis acids. Salts with the tetrakis(pentafluoroethyl)gallate and -indate, [M(C 2 F 5 ) 4 ] - (M=Ga, In), have recently been studied in detail. In contrast to this, work on the syntheses of the free Lewis superacids M(C 2 F 5 ) 3 (M=Ga, In) is scarce and underdeveloped. The hydrates [M(C 2 F 5 ) 3 (OH 2 ) 2 ] proved to be suitable starting materials, particularly due to their thermal stability. Herein we report on synthesis and characterization of reactive adducts, [M(C 2 F 5 ) 3 D], with the weak donor molecules (D) SOCl 2 and Me 3 SiF. The effective Lewis acidities of Ga(C 2 F 5 ) 3 and In(C 2 F 5 ) 3 were experimentally determined by the (modified) Gutmann-Beckett method and their catalytic potential is showcased., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Bidentate and tetradentate chalcogen bonding host systems with SeCF 3 functions as σ-hole donors in close proximity at the alkyne functions of 1,8-diethynylanthracene and its syn -dimer were prepared in quantitative yield by tin-selenium exchange reactions of the corresponding trimethylstannyl precursors with ClSeCF 3 . The bidentate system shows chalcogen bonding interactions with THF, but does not bind halide ions. The tetradentate system cooperatively chelates chloride, bromide and iodide ions with its four CC-SeCF 3 units by rotating the four σ-holes towards the halide ion. The structures of these halide ion adducts were determined by X-ray diffraction. The hydrobromide and -iodide salts of the ethyl derivative of Schwesinger's phosphazene superbase served as halide salts with very weakly coordinating cations.

In the rising field of organoindium chemistry little is known about the perfluoroorganyl-substituted indium compounds. The increasing use of indium reagents is explained by their high stability and tolerance towards water and functional groups. Here we report on the synthesis of the novel tetrakis(pentafluoroethyl)indate, [In(C 2 F 5 ) 4 ] - , and its characterization in salts with the cations [Li(thf) 3 ] + , Cs + , [PPh 4 ] + and [H 14 O 6 ] 2+ (thf=tetrahydrofuran). To the best of our knowledge, these salts constitute the first perfluoroalkylindates and, in general, the first isolated perfluoroalkylindium compounds which are fully characterized by NMR spectroscopy, mass spectrometry, elemental analysis and X-ray diffraction analysis., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Compounds exhibiting main group elements in low oxidation states were found to mimic the reactivity of transition metal complexes. Like the latter, such main group species show a proclivity of changing their oxidation state as well as their coordination number by +2, therefore fulfilling the requirements for oxidative additions. Prominent examples of such main group compounds that undergo oxidative additions with organohalides R-X (R=alkyl, aryl, X=F, Cl, Br, I) are carbenes and their higher congeners. Aluminyl anions, which like carbenes and silylenes oxidatively add to strong σ-bonds in R-X species, have been recently discovered. We present the first anion based upon a Group 14 element, namely the tris(pentafluoroethyl)silanide anion, [Si(C 2 F 5 ) 3 ] - , which is capable of oxidative additions towards C-F bonds. This enables the isolation of non-chelated tetraorganofluorosilicate salts, which to the best of our knowledge had only been observed as reactive intermediates before., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Phosphoranides are interesting hypervalent species which serve as model compounds for intermediates or transition states in nucleophilic substitution reactions at trivalent phosphorus substrates. Herein, the syntheses and properties of stable trifluoromethylphosphoranide salts are reported. [K(18-crown-6)][P(CF 3 ) 4 ], [K(18-crown-6)][P(CF 3 ) 3 F], and [NMe 4 ][P(CF 3 ) 2 F 2 ] were obtained by treatment of trivalent precursors with sources of CF 3 - or F - units. These [P(CF 3 ) 4-n F n ] - (n=0-2) salts exhibit fluorinating (n=1-2) or trifluoromethylating (n=0) properties, which is disclosed by studying their reactivity towards selected electrophiles. The solid-state structures of [K(18-crown-6)][P(CF 3 ) 4 ] and [K(18-crown-6)][P(CF 3 ) 3 F] are ascertained by single crystal X-ray crystallography. The dynamics of these compounds are investigated by variable temperature NMR spectroscopy., (© 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)