Tnfluoroacetylation

The product from fluonnation of sodium acetate is acetyl hypofluorite [64], which IS isolated and characterized [65] The value of this reagent lies in its relative mildness, because it reacts cleanly with most olefins adding the elements of acetoxyl and fluorine [66] Tnfluoroacetyl hypofluorite adds cleanly only to benzylic or electron-rich double bonds... 

Chlorine monofluoride can be tamed by reacting it with cyanunc fluoride to form the trimer (CF2NC1)3 The trimer reacts with 1,1-dichloro 2,2,2 tri fluoroethanesulfenyl chloride to form a mixture of 1 chloro-l,2,2,2-tetra-fluoroethanesulfenyl chlonde and perfluoroethanesulfenyl chloride In the same Way, tnfluoroacetyl bromide yields trifluoroacetyl fluonde[14] (equation 16)... 

Previous efforts to prepare indoles by the cyclization of the corresponding 2-anihno acetals have been largely unsuccessful Flowever, N tnfluoroacetyl-2-amlino diethyl acetal and some derivatives can be converted to indoles in good yield [22] (equation 15)... 

The new reagent 2-trifluoroacetoxypyridine (TFAP) tnfluoroacetylates benzene, benzofuran, and dibenzofuran at -10 to 0 °C in yields ranging from 53 to 93% [45] TFAP converts isopropylbenzene to para-isopropyltrifluoro-acetophenone (equation 30)... 

Ruonnated carboxylic anhydrides and acyl halides as common acylating reagents to convert amines to amides and to acy late suitable heterocyclic nitiogen atoms have already been described in the first edition [10] Like in the acylation at oxygen, much synthetic activity was concentrated m the past few years on the denvatization of biomolecules by fluoroacylation reactions, that is, tnfluoroacetylation of amino sugars,... 

Finally, the synthesis of tnfluoroacetyl isocyanate has been redesigned such that multigram quantities ate produced easily by treatment of tnfluoroaceiyl chlonde with trimethylsilyl isocyanate [52] (equation 26)... 

The rehability of these analytical methods may be questionable when chemical shift differences of derivatives are of the same magnitude as variations encountered from solvent, concentration, and temperature influences. Reported fluorine chemical shift ranges for tnfluoroacetylated alcohols (1 ppm), p-fluorobenzoylated sterols (1 ppm), and p-fluorobenzoylated ammo acids (0.5 ppm) are quite narrow, and correct interpretation of the fluonne NMR spectra of these denvatized mixmres requires strict adherence to standardized sampling procedure and NMR parameters. 

A restricted number of applicable fluonne markers may also be viewed as a Imutabon The tnfluoroacetyl moiety has been the most commonly used group, used m sbidies of ammo acids, steroids, and carbohydrates Enhanced F NMR detection should be possible with specifically designed agents of opumal biological and spectral properbes... 

NITRO-, ETHYL ESTER, ( >], 65 Adipic acid [Hexanedioic acid], 70 DL-Alanine, jV-(tnfluoroacetyl)-, 125 Alcohols, primary, 40... 

Glycine, N- ]/V-(tnfluoroacetyl)glycyl] -, 125 Glycine, N- [ 1 -(tnfluoroacetyl)-L-prolyl] -, ethyl ester, 125... 

DL-Phcnylalamnc,TV-(tnfluoroacetyl), 125 L Phenylalanine,TV (tnfluoroacetyl)-, 125 Phosphine, diphenyl, 45 Phosphine, triphenyl-, 81 Phosphomum, [4-(4-methoxyphenyl)-2-... 

Tnethyloxomum fluoboiate (Oxonium, tnethyl-, tetrafluoroborate(l-)], 59 N Tnfluoroacetylation, 122 Trimethyloxomum fluoborate [Oxonium, tnmethyl-, tetrafluoroborate(l-),... 

Arylphosphonic acid derivatives, 58, 137 Arylphosphonic dichlorides, 58, 136 Aryltetrachlorophosphoranes, 58, 137 L-Asparagine, carbobenzoxy-, 56, 89 L-Asparagine, NJ-(tnfluoroacetyl)- 56, 125 L ASPARAGINYL-L-LEUCINE, CARBOBENZOXY-,METHYL ESTER, 56, 88 Z-Asp Gly-OEt, 56, 93 (l-Azido-3,3-dimethoxy-l-propenyl)ben-zene, 57, 84... 

Triethylamme, hydrochloride, 58, 126 Tnethylcarbinol 58, 27 Triethylene glycol, 57, 31 Triethyloxomum fluoborate, 56, 59 Trifluoroacetic acid, 57, 27 N Tnfluoroacetylation, 56,122... 

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