Sulfur Tetrafluoride Research Articles

ChemInform Abstract: Fluorinations with Sulfur Tetrafluoride and HF. Part 2. Preparation of Trifluoromethylated Thiazoles and Isothiazoles.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform Abstract: Fluorinations with Sulfur Tetrafluoride and HF. Part 1. A Reactor Design for Safe, Routine Handling of SF4, and HF.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Über die Reaktion von Chloroacetyl-2,4,6-trimethylbenzen mit SF 4 in Gegenwart von wasserfreiem Fluorwasserstoff

Reactions of chloroacetic acid with sulfur tetrafluoride and mesitylene give besides chlorofluoroethanes, small yields of 2-chloro-1,1-difluoro-ethylmesitylene and chloro- acetylmesitylene. Our results have shown that in the reaction of chloroacetyl- mesitylene, SF 4 and an excess of HF, formation of 2-chloro-1,1-difluoroethylmesitylene took place. This result shows that the formation of 2-chloro-1,1-difluoroethylmesitylene in the reaction of chloroacetic acid with SF 4 and mesitylene cannot be realized exclusively via fluoroalkylation of mesitylene with CH 2ClCF 2 + cations as previously formulated.

Reactions of organic compounds with SF 4HF, SF 4HFCl 2(Br 2) and SF 4HFS 2Cl 2 systems

Until recently the reactions of sulfur tetrafluoride with organic compounds proceeding with the substitution of hydrogen atom by fluorine have been considered anomalous. An important achievement in sulfur tetrafluoride chemistry, substantially expanding its preparative utility, is the modification of its reactions by using new fluorinating systems, such as SF 4HF, SF 4HFCl 2(Br 2) and SF 4HFS 2Cl 2. We have found SF 4HFX 2 systems are effective in halofluorination and fluorination of various organic compounds in high yields. Results and mechanisms of reactions of alkanes, alkenes, ketones, linear and cyclic esters, heterocyclic compounds with SF 4HFX 2 systems will be discussed. Reactions of aliphatic ketones, alkenes and perfluoralkenes with SF 4HFS 2Cl 2 systems are proposed as a new general convenient route to fluorinated and perfluorinated sulfides, polysulfides and sulfochlorides.

Formation of 1,1,3,3-tetrafluorophthalans in reactions of phthalic and pyromellitic acids with sulphur tetrafluoride

Phthalic and pyromellitic acids were previously reported to react with SF 4 giving the respective bis- and tetrakis(trifluoromethyl)benzenes as sole products. We have found that the reaction with tetrafluorophthalic acid 1a and 4,5-bis(trifluoromethyl)phthalic acid 1b afford, beside the expected poly(trifluoromethyl)benzenes 2a and 2b, considerable amounts of 1,1,3,3- tetrafluorophthalans 3a and 3b. ▪ Similarly, from pyromellitic acids 4a and 4b mixtures of tetrakis(trifluoromethyl)benzenes 5a, 5b, phthalans 6a, 6b and benzodifurans 7a, 7b were obtained. ▪ Structural factors in the acids influencing the competitive formation of (trifluoromethyl)benzenes and cyclic phthalans will be discussed.

Synthesis of gem-chlorofluoro- and -difluro-alkanes

The title compounds are prepared from simple oximes, chlorine and HF. Chlorination of oximes gives gem-chloronitroso derivatives. With no further reagent, these intermediates are transformed, in anhydrous hydrogen fluoride, into gem-chlorofluoro- and -difluoro-alkanes. In a one-step procedure, chlorination of oximes directly in HF leads to the same compounds. This method, which can be performed on a large scale, avoids the use of sulfur tetrafluoride.

An unusual reaction of myo-inositol with sulphur tetrafluoride

Myo-inositol was treated with a mixture of sulphur tetrafluoride and anhydrous hydrofluoric acid to yield a novel compound, the cyclic sulphite ester of 2β,3β-difluoro-7-oxabicyclo[2,2,1]heptane- 5α,6α-diol. The structural assignment and possible mechanism is described.

Fluorinations with sulfur tetrafluoride and HF. 2. Preparation of trifluoromethylated thiazoles and isothiazoles

Several new trifluoromethylated thiazoles and isothiazoles have been prepared using SF 4on precursor carboxylic acids. This chemistry demonstrates the usefulness and applicabilityof the sulfur tetrafluoride fluorination to the preparation of novel thiazoles and isothiazoles.

Fluorinations with sulfur tetrafluoride and HF. 1. A reactor design for safe, routine handling of SF 4 and HF

A reactor has been designed and built to handle anhydrous HF and SF 4 safely for routineuse in organic synthesis. The system described is completely contained and remotelyoperated so as to minimize any possible exposure to these dangerous materials. Furthermore,it features controls that allow the experimentalist to accurately add HF andSF 4, monitor the reaction progress and sample ff necessary, as well as allowing flexibilityin the work-up of the reaction.

Kinetic investigations of the fluorination of carbonyl compounds with sulfur tetrafluoride

Carbonyl groups can be transformed into difluoromethylene groups by SF 4. In the past 20 years a great number of such reactions have been discovered. Lewis acids like HF, BF 3 and AsF 5, preferably HF are used as catalysts. The mechanism of the fluorination reaction is universally discussed by the formation of SF 3 +- and carbenium ions independent of the concrete reaction conditions: ▪ Our kinetic measurements demonstrate that the “ionic mechanism” can only be maintained under conditions showing a great surplus of HF in liquid phase. At higher temperatures in connection with only äquimolar amounts of HF in relation to the ester, especially at temperatures above the critical temperature of HF at 188°C, a “molecular mechanism” is to prefer. Steric hindrances are discussed on the basis of the different mechanisms. By choice of suitable conditions the fluorination reaction can be forced to the different mechanisms.

Alkali Metal Fluorides Supported on Fluorinated γ-Alumina, Lewis Base and Catalytic Properties

Caesium and potassium fluorides supported on fluorinated γ-aluminaare active catalysts for the room temperaturechlorofluorination of sulphur tetrafluoride by chlorinemonofluoride. Maximum catalytic activity is observed at thecomposition 5.5 mmol g -1 in agreement with their behaviourtowards volatile Lewis acids.

A facile synthesis for functional perfluoropolyether oligomers, diacids, diesters, and surfactants

AbstractLinear polyester precursors provide a convenient low cost synthesis for flurocarbon surfactants, diacids, diesters, and intermediates. A reaction scheme starting with hydrocarbon linear polysters followed by conversion of the ester to a perfluoro ester by direct fluorination and subsequent treatment with nonstoichiometric amount of sulfur tetrafluoride produce upon hydrolysis of ester units remaining in the polymer, low molecular weight perfluropolyether diacids. Alternatively, this technique can be altered slightly to produce diesters and other functional perfluorocarbon intermediates.

Structure and electron density of (2,2,2-trifluoro-1-methylethylidene)sulfur tetrafluoride, F4S:C(CH3)CF3

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructure and electron density of (2,2,2-trifluoro-1-methylethylidene)sulfur tetrafluoride, F4S:C(CH3)CF3J. Buschmann, T. Koritsanszky, R. Kuschel, P. Luger, and K. SeppeltCite this: J. Am. Chem. Soc. 1991, 113, 1, 233–238Publication Date (Print):January 1, 1991Publication History Published online1 May 2002Published inissue 1 January 1991https://doi.org/10.1021/ja00001a033RIGHTS & PERMISSIONSArticle Views134Altmetric-Citations16LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (735 KB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

Fluorinated γ-alumina. Catalytic fluorination of 1,1,1-trichloroethane at ambient temperature

γ-Alumina, fluorinated with sulphur tetrafluoride followed by treatment with 1,1,1-trichloroethane, behaves as a catalyst for the room temperature fluorination of CH3CCl3 with anhydrous HF, giving a mixture of chlorofluorohydrocarbons.

Polyhaloaromatics. Part V. Synthesis of poly- and perfluoro-1,3,5,7-tetrahydrobenzo[1,2-c:4,5-c′] difurans

Treatment of dichloro- or dibromopyromellitic acids 1 or 2 with a mixture of sulphur tetrafluoride and hydrogen fluoride gave the respective 4,8-dihalo-1,1,3,3,5,5,7,7-octafluoro-1,3,5,7-tetrahydrobenzo[1,2-c:4,5-c′]difurans ( 3) and ( 4) in high yields. Dichloro compound 3 easily undergoes halogen-exchange with potassium fluoride to give perfluoro-1,3,5,7-tetrahydrobenzo[1,2-c:4,5-c′]difuran ( 5). Reduction of dibromo-compound 4 with lithium aluminium hydride gave, depending on the reaction conditions, 1,1,3,3,5,5,7,7-octafluoro-1,3,5,7-tetrahydrobenzo[1,2-c:4,5-c′]difuran ( 6) or 4-bromo-1,1,3,3,5,5,7,7-octafluoro-1,3,5,7-tetrahydrobenzo[1,2-c,4,5-c′]difuran ( 7).

Pulmonary effects of acute exposure to degradation products of sulphur hexafluoride during electrical cable repair work.

Six electrical workers accidentally exposed to degradation products of sulphur hexafluoride (SF6) during electrical repair work were followed up for one year. One degradation product, sulphur tetrafluoride (SF4), was identified from worksite measurements. Unprotected exposure in an underground enclosed space occurred for six hours over a 12 hour period. Initial symptoms included shortness of breath, chest tightness, productive cough, nose and eye irritation, headache, fatigue, nausea, and vomiting. Symptoms subsided when exposure was interrupted during attempts to identify the cause of the problem. Although exposure ended after several hours, four workers remained symptomatic for between one week and one month. Pulmonary radiographic abnormalities included several discrete areas of transitory platelike atelectasis in one worker, and a slight diffuse infiltrate in the left lower lobe of another. One worker showed transient obstructive changes in tests of pulmonary function. Examination at follow up after one year showed no persistent abnormalities. Preliminary data from this paper were presented at the VIIth international pneumoconioses conference. Pittsburgh, PA, August 1988.

Semiempirical studies on the structure and bonding of fluorosulfuranes and aminofluorosulfuranes

The structures of sulfur tetrafluoride, SF 4, dimethylaminosulfur trifluoride, Me 2NSF 3, and bis(dimethylamino)sulfur difluoride, (Me 2N) 2SF 2 have been investigated using the PM3 semiempirical method. Full geometry optimizations do not agree with experimentally determined geometries. Constraining the F ax-S-F ax angle significantly improves the agreement.

ChemInform Abstract: New Uses of Sulfur Tetrafluoride in Organic Synthesis

ChemInformVolume 21, Issue 40 Reviews ChemInform Abstract: New Uses of Sulfur Tetrafluoride in Organic Synthesis A. I. BURMAKOV, A. I. BURMAKOV Edited by German, L. S.; Zemskov, S. V.; Springer, D-1000 BerlinSearch for more papers by this authorB. V. KUNSHENKO, B. V. KUNSHENKO Edited by German, L. S.; Zemskov, S. V.; Springer, D-1000 BerlinSearch for more papers by this authorL. A. ALEKSEEVA, L. A. ALEKSEEVA Edited by German, L. S.; Zemskov, S. V.; Springer, D-1000 BerlinSearch for more papers by this authorL. M. YAGUPOL'SKII, L. M. YAGUPOL'SKII Edited by German, L. S.; Zemskov, S. V.; Springer, D-1000 BerlinSearch for more papers by this author A. I. BURMAKOV, A. I. BURMAKOV Edited by German, L. S.; Zemskov, S. V.; Springer, D-1000 BerlinSearch for more papers by this authorB. V. KUNSHENKO, B. V. KUNSHENKO Edited by German, L. S.; Zemskov, S. V.; Springer, D-1000 BerlinSearch for more papers by this authorL. A. ALEKSEEVA, L. A. ALEKSEEVA Edited by German, L. S.; Zemskov, S. V.; Springer, D-1000 BerlinSearch for more papers by this authorL. M. YAGUPOL'SKII, L. M. YAGUPOL'SKII Edited by German, L. S.; Zemskov, S. V.; Springer, D-1000 BerlinSearch for more papers by this author First published: October 2, 1990 https://doi.org/10.1002/chin.199040348Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume21, Issue40October 2, 1990 RelatedInformation

Darstellung von 1-amino-3-trifluormethyl-adamantan

The title compound, 1-Amino-3-trifluoromethyl-adamantane, has been synthesized by fluorination of the corresponding carboxylic acid with sulphur tetrafluoride and characterized.

Synthesis and polymerization of ethynylthiophenes and ethynylfurans containing trifluoromethyl groups

Fluorination of thiophenedicarboxylic acid with sulfur tetrafluoride in the presence of anhydrous hydrogen fluoride provided mono and bis(trifluoromethyl)thiophenes in moderate yields. Ethynylthiophenes and ethynylfurans containing trifluoromethyl groups were prepared via 2,2-dichloro-1-fluorovinyl compounds. In polymerizations using transition metal catalysts, 3-ethynylthiophenes gave polymers in high yields, which were soluble in THF and/or fluorocompounds, while 2-ethynylthiophenes polymerized in low yields. In γ-ray induced polymerization, only 2,5-bis(trifluoromethyl)-3-ethynylthiophene afforded the corresponding polymers. Thermal decomposition temperature of polymers obtained increased by introduction of the trifluoromethyl groups as well as the methyl groups.