2,2,2,2-tetrafluoro-5-phenyl

Several comparative studies are available in the literature, which clearly shows that, according to the latest results, tetrafluoro-pheny/ azides (AZ), trifluoro-methyl-phenyl diazirines (DZR), and particularly benzophenone (BP) are the best choice (Scheme 3.). Diazocarbonyl compounds, which played a historically role in the evolution of PAL, can also be considered together with aryl-diazonium salts [6] (not shown). For aryl azides the more common unsubstituted photophore is presented. It should be noted that tetrafluoro-phenyl azides have an increased reactivity towards CH-groups and they do not rearrange. Other substituted phenyl azides can readily alter the excitation wavelength allowing the application of milder or differential photoactivation. 

Phenylantimonic acid reacts with sulfur tetrafluoride at low temperature to form, in high yield, a 1 1 complex of tetrafluoro(phcnyl)-A5-stibane and sulfur tetrafluoride which decomposes on heating at 70 C under vacuum to yield free tetrafluoro(phenyl)-A5-stibanc (23).222... 

The most convenient substrates for fluorination with tetrafluoro(phenyl)-25-phosphane are silyl ethers of alcohols 7.13 17 The trimethylsilylation of alcohols with chlorotrimethylsilane in the presence of pyridine is generally quantitative. 

Table 1. Fluorination of Trimethylsilylated Alcohols with Tetrafluoro(phenyl)-25-phosphanea 5...

The interaction of antimony(III) fluoride with dichloro(phenyl)phosphane leads to oxidative fluorination of the phosphorus atom with the formation of tetrafluoro(phenyl)-/5-phosphane and partial reduction of antimony(III) fluoride to antimony.43... 

Tetrafluoro(phenyl)-A5-stibane (2) is obtained by the reaction of phenylstibonic acid (1) with sulfur tetrafluoride. First the tetrafluoro(phenyl)-25-stibane/sulfur tetrafluoride complex is formed which completely loses the coordinated sulfur tetrafluoride on heating in vacuo.105... 

Thus, aryl-substituted antimony fluorides provide replacement of chlorine by fluorine atoms in aromatic compounds containing trichloromethyl and pentachloro- or dichlorotri-fluoroethyl groups. Their activity as fluorinating agents decreases in the order tetrafluoro(phenyl)-A5-stibane > trifluorodi(phenyl)-25-stibane >antimony(lIl) fluoride dill uorotri(phenyl)-/i.5-stibane. 

N-(2-Fluoro-phenyl) Trifluoro-EI0b, 36 (Ar H -f Ar F) N-(4-Fluoro-phenyl) Trifluoro-EI0b,. 36 (Ar-H -f Ar-E) Carbamidoyl Fluoride N-Phenyl-N-trifluoromethyl- F4, 1208 (Ar-NCS + HgF2 COF2/CsF) Hydroxylamine N-(4-Eihenyl-tetrafluoro-phenyl)- EI6a/l, 5f. (F -b NH-OH)... 

Propanoate Ethyl 3-Oxo-3-(2.3.4.5-tetrafluoro-phenyl)- E10b2. 435 (Educt)... 

Platin Chloro-(t 4-1,5-hexadien)-(2.3.5.6-tetrafluoro-phenyl)-Eltlb,. 426 (Cl -> C6HF4)... 

Iron (ff5-cyclopentadicnyl)-dicarbo-nyl-(4-methyl-tetrafluoro-phenyl)- XIII/9a. 376 Jr, - toluol + [(CO)2Fe — R]Na]... 

Methyl-Radical Tris-[4-nitro-tetrafluoro-phenyl]- EI0b2 64 (CFI C-)... 

Coball (1.2-Bis-(l-methyl-3-oxy-2-butenylidenamino]-cthan)-pyridin-(2,3,4,5-tetrafluoro-phenyl)- Xlll/9b, 15.3 [(F41 ICf,)2IIBr + Co-Kompl./Py]... 

Formyl-tetrafluoro-phenyl)-ElOb, 640 (Ai — F - Ar-Het.) 1-(4- lodo-tetrafluoro-phcnyI)- ElOb,... 

The analogous reaction of tetraphenylstannane and phosphorus pentafluoride in a steel bomb reactor at 135° is reported to give tetrafluoro(phenyl)phosphorane.u... 

This reaction was used originally to demonstrate that tetrafluoro-phenyl groups were present in molecule. 

It should be noted that fluorophosphates are usually highly toxic compounds and, for this reason, fluorination with tetrafluoro(phenyl)-3, -phosphane cannot be recommended. Moreover, other methods usually give better results. 

Sulfane (4-Nitro-tetrafluoro-phenyl)-(pentafluoro-phenyl)-E10 (F - SAr)... 

The mechanism of the formation of organic fluorides from silyl ethers and fluoro-/.5-phosphanes has been studied in some detail for tetrafluoro(phenyl)-25-phosphane.9 The first step, which is usually quantitative at low temperatures, is the formation of an intermediate alkoxyfluoro-25-phosphane 1 and fluorotrimethylsilanc. 

Fluorination of Silyl Ethers with Tetrafluoro(phenyl)-25-phosphane General Procedure 13... 

Copper-catalyzed Direct Phenylation of Indoles. The site-selective direct phenylation of an indole bearing a tetrafluoro-phenyl substituent has been achieved in 64% yield using diphenyUodonium triflate, Cu(OTf)2, and 2,6-di-tert-butylpyridine in dichloromethane (eq 11). This coupUng occurs selectively at the C3 position of the indole ring under copper-catalyzed conditions, with no phenylation occurring at the C2 position of the indole ring or on the tetrafluorophenyl substituent. ... 

Thiirane, 2-phenyl-conformation rotational barriers, 7, 138 polymerization, 7, 144 Thiirane, tetraaryl-synthesis, 7, 175 Thiirane, tetrafluoro-halogenation, 7, 148 polymerization, 7, 144 reactions... 

An in-depth study of the photolysis of a series of fluoro-substituted phenyl azides, e.g. 58, shows clearly that, in general, 3-substituted phenyl azides yield mixtures of the 4,5- and 5,6-disubstitutcd 3//-azepines, e.g. 59 and 60.188 Tri- and tetrafluoro-substituted azidoben-zoates yield NH-insertion products rather than 3//-azepines. 

Originally, 2-diazophenols were used as diazo components. Nowadays the most important compound is 2,5-diethoxy-4-morpholinobenzenediazonium tetrafluoro-borate. Typical coupling components are acetoacetic anilide, l-phenyl-3-carbamido-... 

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