Cyanuric fluoride

Cyanogen fluoride, FCN. Colourless gas (b.p. — 46 C) prepared by pyrolysis of cyanuric fluoride. Polymerizes to (FCN), cyanuric fluoride, at room temperature. 

FLUOROTRIAZINES Riag-fluoriaated triaziaes are used ia fiber-reactive dyes. Perfluoroalkyl triaziaes are offered commercially as mass spectral markers and have been iatensively evaluated for elastomer and hydraulic fluid appHcations. Physical properties of representative fluorotriaziaes are listed ia Table 13. Toxicity data are available. For cyanuric fluoride, LD g =3.1 ppm for 4 h (iahalatioa, rat) and 160 mg/kg (skin, rabbit) (127). 

Trifluoro-l5355-Triazine. Cyanuric fluoride can be produced from 2,4,6-trichloro-j -l,3,5-triaziae [108-77-0] (cyanuric... 

Cyanuric fluoride is readily hydrolyzed to 2,4,6-thhydroxy-l,3,5-triaziae [108-80-5] (cyanuric acid). Cyanuric fluoride reacts faster with nucleophilic agents such as ammonia and amines than cyanuric chloride. 

Fiber-reactive dyes containing the fluorotriaziayl group are based on the condensation of chromophores containing amino groups with 6 - sub s titute d- 2,4- diflu o r o triaziae s. The latter can be prepared from cyanuric fluoride or from the reaction of alkah metal fluorides with... 

The syntheses of fluorotriazine, trichloropyrimidine and chlorodif-luoropyrimidine dyes are completely analogous, using respectively as starting materials cyanuric fluoride (203), 2,4,5,6-tetrachloropyrimidine (204) and 5-chloro-2,4,6-trifluoropyrimidine (205). 

FIGURE 7.19 Reagents for preparing A-protected amino-acid fluorides,55-5661 Boc2-amino-acid fluorides (CyNF),58-59 and a nonbasic acid scavenger (BSA).62 CyNF = cyanuric fluoride DAST = diethylaminosulfur trifluoride TFFH = tetramethylfluoroformamidinium hexafluo-rophosphate BSA = b (trimethylsilyl)acetimide. 

The acid fluoride (3 mmol), obtained from the carboxylic acid and cyanuric fluoride, and TBA-F (5 mg, 0.02 mmol) are added to the silylamine (3 mmol) in MeCN (5 ml) under N2 and the solution is stirred for 6 h at room temperature. The solvent is removed under reduced pressure and the residue is taken up in CH2Cl2. The organic solution is washed with aqueous NaHCO, (5%, 2 x 10 ml), aqueous HCI (4M, 2 x 10 ml) and H20 (20 ml), dried (Na2S04), and evaporated to yield the amide (>75%). 

Trichloro-l,3.5-triazine (cyanuric chloride, 5) can be converted using a sixfold excess of sulfur tetrafluoride at 250 C into 2,4,6-trifluoro-l,3,5-triazine (cyanuric fluoride, 6) with lower proportions of sulfur tetrafluoride, cyanuric chlorofluorides are formed.191... 

An almost quantitative yield of (trifluoromethyl)iminosulfur diiluoride (1), a gas stable up to 600°C, can be obtained by reacting 2,4,6-trifluoro-l,3,5-triazine (cyanuric fluoride) with sulfur tetrafluoride in the presence of cesium fluoride at 1553C.203... 

Deoxygenation of sulfoxides.1 This reaction can be carried out with cyanuric fluoride in dioxanc (3-9 hours, 65 80% yield). Cyanuric chloride (3, 72 4, 522 5, 687 6, 149) can be used in the case of aryl sulfoxides, but alkyl sulfoxides undergo Chlorination with this reagent. 

SULFOXIDES Chlorotrimethylsilane-Zinc. Cyanuric fluoride. Phosphorus triiodide. 

Gobrinoff, M. J. 1967. Exposusre of tyrosine residues in proteins. Reaction of cyanuric fluoride with ribonuclease, a-lactalbumin, and /3-lactoglobulin. Biochemistry 66, 1606-1614. 

To a soln of Fmoc-TOAC-OH (0.437 g, 1.0 mmol) in CH2C12 at —10 °C were added cyanuric fluoride (0.085 mL, lmmol) and pyridine (0.081 mL, lmmol) under nitrogen. After stirring for lh at 0 °C the mixture was directly applied to a silica gel column and eluted with EtOAc/light petroleum ether (1 5). The product eluted first was identified as the oxazol-5(4T/)-one l 51 (0.110 g, 0.026 mmol yield 26%). The fluoride, which was eluted from the column immediately after the oxazolone, was obtained as a thick, orange oil yield 0.308 g (70%) IR (film) 1839,1715 cmA... 

In general, the chemistry of fluoro-l,3,5-triazines resembles that of the chloro derivatives, and therefore will not be discussed in detail. There is evidence that cyanuric fluoride is less reactive than cyanuric chloride in reaction with aniline (76CCC3378). Chambers et al. have reported the isolation of a stable anion cr- complex from the reaction of cyanuric fluoride and cesium fluoride (equation 32) (77JCS(Pl)l605). Such species are believed to be intermediates in the formation of (68) from cyanuric fluoride and perfluoropropene (equation 33). Olah et al. have shown that cyanuric fluoride deoxygenates sulfoxides efficiently (equation 34) (80S221). 

Cyanuric halides are readily synthesized from the cyanogen halides. Cyanuric fluoride is formed at room temperature, whilst cyanuric chloride and cyanuric bromide are prepared... 

Cyanuric fluoride has similar properties to cyanuric chloride. Fibre reactive dyes based on cyanuric fluoride are the subject of a great deal of effort, and they may prove very valuable in the future (B-79MI22004). 

Cyanuric fluoride has been used to modify tyrosine residues, substituting the phenolic hydroxyl group. A maximum of 3 residues in RNase was found to react at pH 10.9 and 25° (148a). However, some mystery surrounds this number, as with other estimates of accessibility, since alkaline-denatured material where all tyrosine residues are available still showed the reaction of only 3 residues with cyanuric fluoride. However, similar observations have been made on iodination in 8 Af urea (11 )- At pH 9.3, Takenaka et al. (149) found that only 2 residues reacted and that 115 was not one of them. Two more reacted after alkali denaturation. Two were resistant under all conditions tested. No enzymic activity data were reported. 

The key step of the approach to 45 is the ring opening of /V-Boc p-lactam 43 with ammonia, Scheme 17. The synthesis starts from the 4-carboxy azetidin-2-one 41, which is a p-hydroxy aspartic acid form possessing the p-carboxyl group and the a-amino moiety simultaneously protected. The dipeptide unit 42 is obtained in 95% overall yield after activation of the a-carboxy group with cyanuric fluoride and... 

The fluorine chemical shifts for fluoropyrimidines, 2-fluoropyrazine, 2-fluoro quinoxaline, 4-fluoroquinazaline, 5-fluorouracil, 5-fluoro-cytosine, and cyanuric fluoride are provided in Scheme 3.82. The fluorine of 2-fluoropyrimidine is considerably deshielded relative to... 

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