Potassium trifluoroacetates

Potassium trifluoroacetate [2923-16-2] M 152.1, m 140-142°, pK 0.52 (for CFjCOjH). To purify dissolve the salt in trifluoroacetic acid with ca 2% of trifluoroacetic anhydride, filter and evaporate carefully to dryness (avoid over heating), and finally dry in a vacuum at 100°. It can be recrystallised from trifluoroacetic acid (solubility in the acid is ca 50.1%). [J Am Chem Soc 74 4746 1952, 76 4285 1954-, J Inorg Nucl Chem 9 166 1959.]... 

In 2000, Rhodia began the production of triflic acid by a new process, which includes sulfination of potassium trifluoroacetate, oxidation of the resulting potassium triflinate, followed by acidification and purification23 [Eq. (2.11)]. 

This technique is useful for monomers which are difficult to polymerize by other techniques. Thus, chlorotrifluoroethylene can be polymerized anodically with good efficiency by electrolysis in liquid hydrogen fluoride - potassium fluoride or trifluoroacetic acid - trifluoroacetic anhydride - potassium trifluoroacetate 631 ... 

HFA reacts with trifluoroacetyl nitrite in the presence of potassium fluoride to yield potassium trifluoroacetate and heptafluoroisopropyl nitrite (171). 

Thermal reaction of potassium trifluoroacetate with diaryl disulfides 30 is a useful method for effecting the synthesis of aryl trifluoromethyl sulfides 31 (see Table 3), ... 

Table 3. Thermal Reaction of Potassium Trifluoroacetate with Diaryl Disulfides 30 ...

In a search for an aprotic solvent for acidity function studies with (Li, Na, K) acetate eutectic at200°C (Na, K)SCN was suitably miscible however, even small concentrations (1 %) inhibited the known reaction of trimethylol-ethane, which probably requires proton abstraction by the acetate anion to form an alkoxide intermediate. Since haloacetates are weaker bases than acetates, these salts were considered for diluents. Potassium trifluoroacetate (mp 135-I37°C), reported to be the most stable member of the series, was prepared from potassium hydroxide and excess trifluoroacetic acid with vacuum drying and fractional recrystallization from absolute alcohol. DTA of the white crystalline product detected decomposition as low as 125°C. Since the molten salt decomposed with bubbling at I45-150°C, this effort was discontinued. 

The alkylation of thiophenes with a glyoxylate imine to give an a-aminoester has been achieved using an iron(III) catalyst. The mechanism in the case of 2-ethylthiophene is thought to involve co-ordination of the catalyst to the imine, allowing reaction with the thiophene through the intermediate (63). The reaction of a ,/3-unsaturated iminium ions with pyrrole is slow when only weakly basic counterions are present. However, in the presence of potassium trifluoroacetate, rapid deprotonation of the intermediate, (64), allows the rate constant for rate-determining carbon-carbon bond formation to be measured. 

Toluene, tetrahydrofurane, chloroform, 2-(4-hydroxyphen-ylazo)benzoic acid (HABA), potassium trifluoroacetate, aflyl alcohol, succinic anhydride, naphthaline, potassium, and (l-ethyl-3-(3-dimethylaminopropyl)carbodiimid hydrochloride (EDC) were purchased from Sigma-Aldrich, Germany, in highest quality. Diethoxydimethylsilane (D), methyltrimethoxysilane (T), triethoxysilane (T-H) and tetramethyldisiloxane (M-H) were obtained from Wacker Chemie, Germany. Dodecylbenzenesulfonic acid (DBS), p-chloromethylphenyltrimethoxysilane (ClBz-T) and the Karstedt-Catalyst were purchased from ABCR, Germany. 

Buchwald and Chen have reported an effieient Cu-mediated flow approaeh to eonvert aryl- and heteroaryliodides to their trifluoromethylated derivatives using stable, inexpensive, easy to handle potassium trifluoroacetate as the... 

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