Pentafluorobenzoic acid

Replacement of hydroxyl by fluorine converts perfluoroalkanecarboxylic acids toperfluoroalkanoylfluorides The short chain acids react exothermally with FAR added in a dropwise manner, whereas the longer chain acids require heating [78] (equation 49) Attempts to fluorinate pentafluorobenzoic acid with FAR leads to decarboxylation to give pentafluorobenzene [78]... 

Alkaline hydrolysis of pentafluorobenzoic acid, the probable intermediate in the alkaline hydrolysis of perfluorotoluene, gives a high yield of p-hydroxytetra fluorobenzoic acid [9, 10 (equation 10)... 

Polyfluorobenzyl alcohols are one class of fluorinated starting materials for medicinal and agricultural usage. Practical electrochemical methods for the product-selective synthesis of polyfluorobenzyl alcohols have been developed [79, 80], 2,3,4,5,6-Pentafluorobenzoic acid is reduced selectively to 2,3,4,5,6-pentafluorobenzyl alcohol at amalgamated lead, zinc and cadmium cathodes in aqueous sulfuric acid solutions, while 2,3,5,6-tetrafluorobenzyl alcohol can also be obtained selectively by using the non-amalgamated cathodes in solutions containing small amounts of a quartemary ammonium salt [79],... 

J. D. Cox, H. A. Gundry, A. J. Head. Thermodynamic Properties of Fluorine Compounds. Part 1. Heats of Combustion ofp-Fluorobenzoic Acid, Pentafluorobenzoic Acid, Hexafluorobenzene, and Decafluorocyclohexene. Trans. Faraday Soc. 1964, 60, 653-665. 

Fig. 4 High-resolution solid-state NMR spectrum of the 1 1 cocrystal containing benzoic acid (BA) and pentafluorobenzoic acid (PFBA). The two peaks at ca. 174 ppm represent the carboxylic acid group of PFBA and the two peaks at ca. 167 ppm represent the carboxylic acid group of BA...

Pentafluorobenzoic acid [602-94-8] M 212.1, m 101-103 , 103-104 , 104-105 , 106-107 . Dissolve in Et20, treat with charcoal, filter, dry (CaSO4), filter, evaporate and recrystallise residue from pet ether (b 90-100°) after adding a little toluene to give large colourless plates. UV (H2O) Xmax 265nm (e 761). The S-benzylisothiuronium salt has m 187° after recrystn from H2O. [McBee and Rapkin JACS 73 1366 1951-. Nield et al. JCS 166, 170 7959]. 

FLUORINECOMPOUNDS,ORGANIC - FLUORINATED AROMATIC COMPOUNDS] (Volll) Pentafluorobenzoic acid [602-94-8]... 

Alkaline hydrolysis of pentafluorobenzoic acid gives a high yield of perfluoro-4-hydroxybenzoic acid (4),35 -37... 

Pentafluorobenzoic acid with sodium methoxide yields tetrafluoro-4-methoxybenzoic acid (24).98... 

Pentadiene 2,3-Pentadiene Pentaerythritol Pentaerythritol tetranitrate Pentafluorobenzoic acid Pentafluoroethane Pentafluorophenol Pentamethylbenzene... 

This mode of interaction has been empirically observed in the crystal structures of the cocrystals formed by benzamide and pentafluorobenzoic acid [15,16]. 

The other hydrophilic organics identified in the various water samples are generally much less abundant (ppb levels), and consist mainly of carboxylic acids. A trace of the organic groundwater tracer pentafluorobenzoic acid (added to the cap of experimental trench section 4) was detected in water from sump S4 in expermental trench section 4 (sampled 8/18/81). A trace of this compound was also detected in water from waste trench 27 (sampled on 4/7/81), as a result either of subsurface transport in... 

Pentafluorobenzoic acid reduced selectively to either 2,3,5,6-tetrafluorobenzyl alcohol (87) or 2,3,5,6-tetrafluorobenzaldehyde (88) at a lead cathode in dilute sulfuric acid in the presence of quaternary ammonium salts75(equation 51). This is an interesting reaction that could involve loss of fluoride ion from an intermediate radical anion followed by further reduction (Scheme 5). 

Acylation of pentafluorobenzene to form ketones either with acid halides or with anhydrides has been achieved with excess SbFg [22]. Use of phosgene in place of acid chlorides results in the formation of pentafluorobenzoic acid in good yield [4]. 

Another regioselective hydrogenolysis of fluorine with hydrides takes place in perfluorotoluene, and electrolytically in pentafluorobenzoic acid (equations 25 and 26). ... 

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