Trifluoromethanesulfonic acid, properties

When the olefinic precursor to 866 was treated briefly with trifluoromethanesulfonic acid in dichloromethane solution, cyclization occurs with installation of the final dodecahedrane framework bond. The predominant product proved to be 557 in which methyl group migration has also taken pla( °l The symmetry of this first dodecahedrane was apparent from its spectral properties and nicely detailed... 

All these electrolytes are neutral in Bronsted acid-base properties. Although rather exceptional, an acid, a base, or a pH buffer may be added to the supporting electrolyte of neutral salts. The acid-base system to be selected depends on the purpose of the measurement. We often use trifluoromethanesulfonic acid (CF3S03F1) as a strong acid acetic acid, benzoic acid, or phenol as a weak acid an amine or pyridine as a weak base and tetraalkylammonium hydroxide (ILtNOH) as a strong base. Examples of buffer systems are the mixtures of picric acid and its R4N-salt and amines and their PlCl04-salts. Here, we should note that the acid-base reactions in aprotic solvents considerably differ from those in water, as discussed in Chapter 3. 

Trifluoromethanesulfonic Acid. Trifluoromethanesulfonic acid (CF3SO3H, triflic acid), the first member in the perfluoroalkanesulfonic acid series, has been studied extensively, and excellent reviews describing its physical and chemical properties have been published.18,19 Besides its preparation by electrochemical fluorination of methanesulfonyl halides,20 triflic acid may also be prepared from... 

Hydrogen Fluoride-Trifluoromethanesulfonic Acid. The acidity of this binary Brpnsted acid system has not been measured, but the superacidic properties are mentioned in numerous patents concerning fluorination, olefin alkylation, and hydrocarbon conversion. 

Redox properties. For oxidation of [Os(terpy)2]2+ see below. Treatment of [Os(terpy)(bipy)Cl]+ with trifluoromethanesulfonic acid gives [H20—Os(terpy)bipy]2+, and it has been shown by electrochemical and spectrophotometric studies (equation 1) to be a member of the series (at pH 7).194... 

The ready availability of the strong anhydrous acids fluorosulfuric acid and trifluoromethanesulfonic acid in recent decades prompted more chemistry 179). The electron-withdrawing properties of the CF3—, F—, and —SO2— groups suggested that FSO3 and CF3S03 ... 

More tractable and potentially useful polyether ketones, incorporating phenylene-carborane-phenylene units, and with properties suitable for high temperature applications, have been prepared by acylation reactions (using trifluoromethanesulfonic acid as both medium and catalyst) between appropriate dicarboxylic acids and phenoxyphenylcarboranes. For example, the polyetherketone 20 (Scheme 3.6), derived from bis(4-phenoxyphenyl)-para-carborane and biphenyl-4,4 -dicarboxylic acid, is essentially amorphous on isolation from trifluoromethanesulfonic acid, but crystallizes when heated above its glass transition temperature (267°C) before hnally melting at about 390 0... 

The chemical and physical properties of trifluoromethanesulfonic acid and derivatives were thoroughly reviewed22. Since triflate has a good leaving ability, alkyl triflates can be used for the determination of nucleophilicities of weak nucleophiles such as arylsulfonate... 

Synonyms Methanesulfonic acid, trifluoro-, methyl ester Trifluoromethanesulfonic acid, methyl ester Empirical C2H3F3O3S Properties Colorless to brn. liq. sol. in 95% ethanol insol. in water reacts exothermically with DMSO m.w. 164.10 sp.gr. 1.450 (20/4 C) b.p. 94-99 C flash pt. 38 C ref. index 1.3244 (20 C) Toxicology Toxic by inh., ing., skin contact corrosive causes burns extremely destructive to tissues of eyes, skin, mucous membranes, upper respiratory tract risk of irreversible effects inh. may cause spasm, inflamm./edema of larynx/bronchi, chem. pneumonitis, pulmonary edema may cause burning... 

Like for sihcon, germanium was synthesized as an organo-trifluoromethanesulfonate [(C6H5)3Ge(0S02CF3)] but no information concerning the Lewis acid properties of this compound has been reported to date [22]. 

Another unconventional RTIL, trifluoromethanesulfonic acid monohydrate HsO" " CFsSOs (hydronium trufluoromethane sulfonate), was first characterized by Gramstad and Haszeldine [16] as a white stable solid with a melting point of 34 °C. Some of its properties as an ionic liquid were subsequently reported by Corkum and Milne [17], who refined its freezing point to 36 °C (whereas the... 

Sarada T, Granata RD, Foley RT (1978) Properties of trifluoromethanesulfonic acid monohydrate pertinent to its use as a fuel cell electrolyte. J Electrochem Soc 125 1899-1906... 

A review of solvent properties of, and organic reactivity in, ionic liquids demonstrates the relatively small number of quantitative studies of electrophilic aromatic substitution in these media.3 Studies mentioned in the review indicate conventional polar mechanisms. 1-Methylpyrrole reacts with acyl chlorides in the ionic liquid 1-butylpyridinium tetrafluoroborate to form the corresponding 2-acylpyrrole in the presence of a catalytic amount of ytterbium(III) trifluoromethanesulfonate.4 The ionic liquid-catalyst system is recyclable. Chloroindate(III) ionic liquids5 are catalytic media for the acylation, using acid chlorides and anhydrides, of naphthalene, benzene, and various substituted benzenes at 80-120 °C. Again the ionic liquid is recyclable. 

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