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Structure and chemistry of sulfur tetrafluorideGoettel, James T January 2013 (has links)
Sulfur tetrafluoride was shown to be a useful reagent in preparing salts of ReVIIO2F4−, IVOF4−, and IVIIO2F4−. Sulfur tetrafluoride reacts with oxo-anions in acetonitrile or anhydrous HF (aHF) via fluoride-oxide exchange reactions to quantitatively form oxide fluoride salts, as observed by Raman and 19F NMR spectroscopy. Pure Ag[ReO2F4] as well as the new CH3CN coordination compounds [Ag(CH3CN)2][ReO2F4] and [Ag(CH3CN)4][ReO2F4]•CH3CN were prepared. The latter was characterized by single-crystal X-ray diffraction. The reaction of [N(CH3)4]IO3 with SF4 in acetonitrile gave the new [N(CH3)4][IOF4] salt.
Sulfur tetrafluoride forms Lewis acid-base adducts with pyridine and its derivatives, i.e., 2,6-dimethylpyridine, 4-methylpyridine and 4-dimethylaminopyridine, which have recently been identified in our lab. In the presence of HF, the nitrogen base in the SF4 base reaction systems is protonated, which can formally be viewed as solvolysis of the SF4•base adducts by HF. The resulting salts have been studied by Raman spectroscopy and X-ray crystallography. Crystal structures were obtained for pyridinium salts: [HNC5H5+]F−•SF4, [HNC5H5+]F−[HF2−]•2SF4; 4-methylpyridinium salt: [HNC5H4(CH3)+]F−•SF4, [HNC5H4(CH3)+][HF2−]; 2,6-dimethylpyridinium salt: [HNC5H3(CH3)2+]2[SF5−]F−•SF4; 4-dimethylaminopyridinium salts: [HNC5H4N(CH3)2+]2[SF5−]F−•CH2Cl2, [NC5H4N(CH3)2+][HF2−]•2SF4; and the 4,4’-bipyridinium salts: [HNH4C5−C5H4N+]F−•2SF4, [HNH4C5−C5H4NH2+]2F−•4SF4. These structures exhibit a surprising range of bonding modalities between SF4 and fluoride and provide an extensive view of SF4 in the solid state.
For the first time, the solid-state structure of SF4 was elucidated by single-crystal X-ray diffraction. The structure can best be described as a network with weak intermolecular S---F contacts formed exclusively by the axial fluorines that exhibit more ionic character. A similar structural motif was found in the novel [HNC5H3(CH3)2+]2[SF5−]F−•4SF4 salt which contains layers of SF4.
Adduct formation of SF4 with oxygen-bases was observed for the first time. These SF4•O-base adducts (SF4•OC4H8, SF4•(OC4H8)2, SF4•(CH3OCH2)2, SF4•(O=C5H8)2) were synthesized, isolated, and characterized at low temperatures. The structures were elucidated by X-ray crystallography and Raman spectroscopy. The characterization of the SF4•ketone adduct (SF4•O=C5H4) is of great significance, since SF4 can serve as a fluorinating agent towards carbonyl groups. These adducts offer the first extensive view of dative O---S(IV) bonds. / xviii, 177 leaves : ill. ; 29 cm
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High-resolution infrared spectroscopy of SFâ‚„ and other short-lived speciesRaffael, Kevin January 2002 (has links)
No description available.
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Lewis-acid and fluoride-ion donor properties of SF₄ and solid-state NMR spectroscopy of Me₃SnFChaudhary, Praveen, University of Lethbridge. Faculty of Arts and Science January 2011 (has links)
Trimethyltin fluoride (Me3SnF) is a useful fluorinating agent in organometallic
chemistry. Its solid-state structure has been investigated by X-ray crystallography
showing a polymeric fluorine-bridged structure. Disorder, however, has precluded the
accurate refinement of all structural parameters. In order to obtain accurate structural
information, trimethyltin fluoride was investigated using high-resolution 13C, 19F, and
119Sn solid-state NMR spectroscopy using a four-channel HFXY capability. The
119Sn{1H} solid-state NMR spectrum agrees with pentacoordination about Sn in this
compound. The high-resolution 119Sn{19F, 1H}, 13C{1H,19F} and 19F{1H} NMR spectra offer unambiguous determination of 1J(119Sn-19F) and 1J(119Sn-13C) coupling constants. Furthermore, the analysis of the 119Sn{19F, 1H}, 119Sn{1H}, and 19F{1H} MAS spectra as a function of spinning speed allowed for the determination of the 119Sn CSA and J anisotropy, as well as the 119Sn-19F dipolar couplings. These were determined via SIMPSON simulations of the 13C, 19F, and 119Sn NMR spectra. Finally the 119Sn{19F, 1H} revealed fine structure as the result of 119Sn-117Sn two bond J-coupling, seen here for the first time. Sulfur tetrafluoride can act as a Lewis acid. Claims had been presented for the formation of an adduct between SF4 and pyridine, but no conclusive characterization had been performed. In the present study, adducts of SF4 with pyridine, lutidine, 4-picoline and triethylamine were prepared and characterized by low-temperature Raman spectroscopy. Sulfur tetrafluoride also acts as a fluoride-ion donor towards strong Lewis acids, such as AsF5 and SbF5, forming SF3
+ salts. Variable-temperature (VT) solid-state 19F NMR spectroscopy showed that SF3
+SbF6 – exists in three phases with phase transitions at ca. –45 and –85°C, while SF3
+AsF6 – exists only as one phase between +20 and –150 °C. The phases of SF3
+AsF6 – were also characterized by VT Raman spectroscopy. / xvi, 170 leaves : ill. (some col.) ; 29 cm
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Syntheses, Structures, and Applications of Inorganic Materials Functionalized by Fluorine / フッ素により機能化された無機材料の合成、構造、ならびに応用Yamamoto, Hiroki 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(エネルギー科学) / 甲第23295号 / エネ博第420号 / 新制||エネ||80(附属図書館) / 京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻 / (主査)教授 萩原 理加, 教授 野平 俊之, 教授 坂口 浩司 / 学位規則第4条第1項該当 / Doctor of Energy Science / Kyoto University / DFAM
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