Pentafluoro

Pentafluoro 6 nitrobenzene reacts readily with sodium methoxide m methanol at room temperature to yield two major products each having the molecular formula C7H3F4NO3 Suggest reasonable structures for these two compounds... 

The formation of ethyl cyano(pentafluorophenyl)acetate illustrates the intermolecular nucleophilic displacement of fluoride ion from an aromatic ring by a stabilized carbanion. The reaction proceeds readily as a result of the activation imparted by the electron-withdrawing fluorine atoms. The selective hydrolysis of a cyano ester to a nitrile has been described. (Pentafluorophenyl)acetonitrile has also been prepared by cyanide displacement on (pentafluorophenyl)methyl halides. However, this direct displacement is always aecompanied by an undesirable side reaetion to yield 15-20% of 2,3-bis(pentafluoro-phenyl)propionitrile. 

Oxidation of perfbtoroquinobne by fuming nitric acid yields pentafluoro-5,8-dioxo-5,8-dihydroquinoline or hexafluoro-2 oxo-l,2-dihydroquinoline in low yields ]98 (equation 90)... 

Pentafluoroethanesulfonic acid (penrflic acid) is prepared by an improved procedure over previously reported methods through the use of pentafluoro-ethyllithium [64] (equation 31). 

Trifluoromethylalion of aryl iodides was carried out by the fluoride ion in duced cross-coupling reaction of aromatic iodides with tnfluoromethyltnalkyl-silanes in the presence ofcopper(I) salts [219 (equation 147) Some pentafluoro- ethyl derivative was also formed This methodology was extended to pentafluoroethyl-and heptafluoropropyltriethylsilanes [2/9]... 

A polyfluorinated P,y-unsaturated ketone is formed m situ from tributylamine and 3,4-bis(tnfluoromethyl)-3-(pentafluoroethyl)-5,5,6,6,6-pentafluoro-2-hex-anone. The enol form of the unsaturated ketone cyclizes via an intermolecular addition-elimination reaction that involves exclusive attack by oxygen rather than by carbon. This reaction demonstrates the hardness of a F-C= site toward... 

Fluoride ion produced from the nucleophilic addition-elimination reactions of fluoroolefins can cataly7e isomerizations and rearrangements The reaction of per fluoro-3-methyl-l-butene with dimethylamine gives as products 1-/V,/Vdimeth-ylamino-1,1,2,2,4,4,4-heptafluoro-3-trifluoromethylbutane, N,W-dimetliyl-2,2,4,4,4-pentafluoro 3 trifluoromethylbutyramide, and approximately 3% of an unidentified olefin [10] The butylamide results from hydrolysis of the observed tertiary amine, and thus they share a common intermediate, l-Al,A -dimethylamino-l,l 24 44-hexafluoro-3-trifluoromethyl-2-butene, the product from the initial addition-elimination reaction (equation 4) The expected product from simple addition was not found... 

Tetrafluorobenzyne, generally generated by the treatment of pentafluoro-benzene with butyllithium at -78 °C in ether in the presence of the substrate diene, is a versatile dienophile [9, 103, 104], In an interesting study of the use of substituted benzynes to synthesize isoindoles, tetrafluorobenzyne, 4-fluorobenzyne, and 4-(tntIuoromethyl)benzyne were shown to react in moderate yields with A7-(trimethylsiIyl)pyrroles, with the adducts being easily converted to the respective fluorinated isoindoles [705] (equation 87). 

Reaction of 2-aminopyridine and 2,3,4,5,6-pentafluoro- and 5-nitro-2-fluorobenzoyl chloride in CH2CI2 in the presence of (/-Pr)2EtN at room temperature afforded 1,2,3,4-tetrafluoro- and 8-nitro-l l//-pyrido[2,l-6]-quinazolin-11-ones, respectively (01TL1851). 

A useful route to 2,1,3-benzothiadiazoles is the F -catalyzed cyclization of l-(4-X-C6F4)-3-trimethylsilyl-l, 3-diaza-2-thiallenes [90JFC(50)359]. Fluoride ion catalysis is also used in the formation of heterocycles from pentafluorobenzoyl and -phenoxy compounds (81BCJ3447). Pentafluoro-phenylcarbonimidoyl dichloride with primary amines gave guanidines,... 

If necessary, the nucleosides can be hydrolyzed to the sugar and the base by heating in formic acid.2 Kresbach et al.3 have used pentafluoro-benzylation combined with negative Cl for the detection of trace... 

Propanone, l-chloro-l,l,3,3,3-pentafluoro-] (b.p. 7.8° available from PCR, Inc. or Allied Chemical Corp.) are combined in a flask fitted with a dry ice condenser and a magnetic stirring bar. The refluxing mixture is stirred for 4-0 hours and then allowed to warm gradually to room temperature. The contents of the flask are extracted three times with anhydrous ether, and the combined extracts are distilled at atmospheric pressure. After the ether has been removed, continued distillation gives 22.8-28.5 g. (55-69%) of l,l,l-trichloro-3,3,3-trifluoroacetone, b.p. 83.5-84.5°, infrared (film) 1790 cm. - This compound is stored at room temperature in a tightly stoppered bottle. In the absence of reliable toxicity data, it should be handled with normal precautions. 

Tellurium, bis(methyldithiocarbonato)-stereochemistry, 1,60 Tellurium, dichlorodimethyl-lone electron pair, I, 44 Tellurium, pentafluoro-lone electron pair structure, 1,50... 

Pentafluorophenylcopper tetramer Copper, tetrakis(pentafluoro-phenyl)tetra- (8,9) (34077-61-7)... 

The metabolism of pentafluoro-, pentachloro-, and pentabromophenol by Mycobacterium fortuitum strain CG-2 is initiated by a monooxygenase that carries out hydroxylation at the para position (Uotila et al. 1992). Cell extracts of Rhodococcus chiorophenoiicus Mycobacterium chlorophenolicunt) strain PCP-1 in the presence of a reductant transformed tetrafluoro-, tetrachloro-, and tetrabromohydroquinone to 1,2,4-trihydroxybenzene by reactions that clearly involve both hydrolytic and reductive loss of fluorine (Uotila et al. 1995). 

Sulfur pentafluoride derivatives are of considerable industrial interest [15], The solubility of the di(p-nitrophenyl) disulfide in acetonitrile is too low to undergo a similar pathway as given in [GL 9], Therefore, the better soluble trifluorothio-m-nitrobenzene was used, leading to the further fluorination of this substrate to the pentafluoro derivative as given here. 

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