Hexafluoroisopropyl alcohol

Fluoroall l-SubstitutedTitanates. Tetraliexafluoroisopropyl titanate [21416-30-8] can be prepared by the reaction of TiCl and hexafluoroisopropyl alcohol [920-66-17, in a process similar to that used for TYZOR TPT (7). Alternatively, it can be prepared by the reaction of sodium hexafluoroisopropoxide and TiCl ia excess hexafluoroisopropyl alcohol (8). The fluoroalkyl material is much more volatile than its hydrocarbon counterpart, TYZOR TPT, and is used to deposit titanium on surfaces by chemical vapor-phase deposition (CVD). 

Trifluoromethyl-l-phenylethyl tosylate has been used to differentiate as shown in Table 1, the solvolytic power of three fluorinated solvents and to compare these with formic and acetic acids The three fluorinated solvents are trifluoroacetic acid, trifluoroethanol, and 1,1,1,3,3,3-hexafluoroisopropyl alcohol [55]... 

Fig. 21.—Circular Dichroism of Chitin in 1,1,1,3,3,3-Hexafluoroisopropyl Alcohol Solution...

Hexafluoroantimonic acid, 3 65 Hexafluorogallates, 22 357 Hexafluoroisopropyl alcohol (HFIPA), 25 177... 

Additional photoresist materials containing 1,1,1,3,3,3-hexafluoroisopropyl alcohol, (I) and (II), were prepared by Harada et al. (1) and Maeda et al. (2), respectively, and used in lithographic applications. 

Hexafluoroacetone is a reactive electrophile. It reacts with activated aromatic compounds (e.g., phenol), and can be condensed with olefins, dienes, ketenes, and acetylenes. It forms adducts with many compounds containing active hydrogen (e.g., H.,0 or HCN). Reduction of HFA with NaBH or LiAlH affords the useful solvent hexafluoroisopropyl alcohol. The Industrial importance of HFA arises largely from its use 1n polymers and as an... 

The oxyphosphoranes are made from the reaction of a trivalent phosphorus compound with a carbonyl compound. 6 DMF=dimethyl-formamide HFIP=hexafluoroisopropyl alcohol. c l-Phospha-2,8,9-trioxaadamantane. d ca. 0-2m soln. ca. 1m soln. tea. 2m soln. 

The submitters report that oxidation of phenyl methyl sulfide to phenyl methyl sulfoxide also can be achieved selectively by using hexafluoroisopropyl alcohol (HFIP) as the solvent the reaction is complete after 10 min. 

The present procedure is based on the use of fluoroalkyl alcohols as solvents in oxidation reactions. The method is efficient and versatile, and produces disulfides and sulfoxides under mild conditions. These reactions have also been developed using hexafluoroisopropyl alcohol (HFIP) as solvent with a large variety of substrates (alkyl sulfides, alkyl thiols, vinyl sulfides, fiuorinated vinyl sulfides, thioglucosides) by Begue et al."> Replacement of HFIP with trifluoroethanol, a more common and less expensive solvent, also allows the use of mild conditions and affords high yields of disulfides and sulfoxides without contamination. 30% Aqueous hydrogen peroxide is inexpensive and, since water is the sole byproduct, this method is environmentally friendly. 

Hexafluoroisopropyl Alcohol Hexafluorosific Acid Hexafluoroutanfum Hexameth y tenototra m Ine Hexamathylphosphoric TriamIde... 

We first applied the solvatochromic equation (SCE) to solvolysis of tert-butyl chloride (t-BuCl) to determine if the method could give a reasonable result for this much-studied reaction (7). Abraham et al. (11) had previously attempted correlation of these rates with the SCE without the cavity term, but as Bentley and Carter (12) have noted, an unsatisfactory result was achieved (7). First, TFE and hexafluoroisopropyl alcohol (HFIP) did not fit the correlation. Second, no rate dependence on solvent nucleophilicity 0 was found, despite other works indicating a weak dependence on this parameter (12, 13). Also, different correlations were observed for hydroxylic and nonhydroxylic solvents Bentley considered this finding to indicate that the dehydrohalogenation transition state (in nonhydroxylic solvents) and the solvolysis transition state (in hydroxylic solvents) were significantly different and thus concluded that the two types of reactions should not be included in the same correlation. 

Two particularly significant new sources of experimental data have been developed during the past 20 years or so. Solvents of low nucleophilicity were examined, for example, TFA (14), trifluoroethanol (TFE) (15), and hexafluoroisopropyl alcohol (HFIP) (16, 17). Also, the field of gas-phase ion chemistry has expanded rapidly, and data on intrinsic gas-phase reactivity provide important supporting evidence for our interpretations of the kinetic data. 

The specific rates of solvolysis have been found to vary very little with the solvent. For 41 solvent systems, the specific rates at 70.4 °C varied only by a factor of less than 7, from 1.09 X 10-6 s-1 in terf-butyl alcohol to 7.09 X 10-6 s-1 in 97% hexafluoroisopropyl alcohol (HFIP). This lack of variation is even more remarkable considering the large temperature dependence, as reflected in enthalpies of activation of approximately 35 kcal/mol. Reasonable rates are observed at moderate temperatures only because of entropies of activation of approximately +18 eu. 

For comparative purposes, the solvolytic rate constants for I-VI at 25 °C in hexafluoroisopropyl alcohol (HFIP) are given in Table I, together with the m values, which measure the dependence of the rates on the solvent ionizing power parameter OTs by the equation log (k/k0) = raY0Ts (3, 6). 

An oven-dried (Note 1), 300-mL, three-necked, round-bottomed flask containing a magnetic stirring bar, and fitted with a rubber septum inlet, a thermometer and a balloon full of nitrogen is charged with 100 mL of dry tetrahydrofuran (Note 2) and 6.3 ml (60 mmol) of hexafluoroisopropyl alcohol (Note 3). The flask and its contents are cooled to -70°C with a dry ice/acetone bath. After the apparatus has cooled, 76.9 mL of a 1.6 M hexane solution of butyllithium (123 mmol) is added dropwise using a 100-mL syringe over a period of 15 min. The reaction temperature is kept below -40°C (Note 4). After the addition is complete, the reaction mixture is further stirred for 10 min at -70°C and warmed to 0°C with an ice bath for 1 hr to afford lithium pentafluoropropen-2-olate, 1, (Note 5). To the pale yellow solution is added dropwise... 

Hexafluoroisopropyl alcohol was obtained from Central Glass Company, Ltd., and used without additional purification. It is advisable to keep this reagent under a nitrogen atmosphere because it is highly hygroscopic. 

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