Pentafluoroethyl iodide

Antiprogestine, substituted at C-17 by a hydroxyl 7-P) and a C2F5 group (17-a), is an antagonist of the progesterone receptor. It is currently in early clinical development. C2F5 is introduced with pentafluoroethyllithium, prepared in s/ fufrom pentafluoroethyl iodide and butyllithium (Fig. 61) [148]. 

Antiprogestine (ZK-230211) is a progesterone receptor antagonist developed for treatment of breast tumors. It is substimted at C-17 by a hydroxyl (17P) and a C2F5 group (17a), which is introduced with pentafluoroethyUithium, prepared in situ from pentafluoroethyl iodide and butyllithium (Figure 8.78). ... 

Neat dimethyl tellurium and trifluoromethyl iodide or pentafluoroethyl iodide reacted under UV irradiation to give bis[perfluoroalkyl] telluriums and methyl perfluoroalkyl telluriums. The bis[perfluoroalkyl] telluriums could not be completely separated from the unsymmetrical tellurium compounds by trap-to-trap distillation. The yields are strongly influenced by the molar ratios of the reactants. The products were isolated as yellow, odorless liquids3. 

The presence of an approximately equimolar amount of triethylamine in the reaction mixture binds the methyl iodide formed in the reaction, shifts the equilibrium of the reaction toward the products, and prevents the quatemization of diorgano tellurium products4. Whereas pentafluoroethyl iodide requires photochemical stimulation, hep-tafluoroisopropyl iodide does not4. 

Reaction of Pentafluoroethyl Iodide with Potassium Hydroxide and Water... 

What are the compounds resulting from treatment of pentafluoroethyl iodide with potassium hydroxide Explain the result. 

Commercial telomerization usually involves the reaction of pentafluoroethyl iodide (telogen) with tetrafluoroethylene oligomers (taxogen) in the presence of a catalyst, to produce a perfluoroalkyl iodide polymer (telomer) ... 

Methyl Pentafluoroethyl Tellurium A mixture of 9.0 g (57.1 mmol) dimethyl tellurium and 17.9 g (72.8 mmol) pentafluoroethyl iodide is treated with 2.3 g (22.8 mmol) triethylamine at — 78° in a flask equipped with a low-temperature reflux condenser. The mixture is allowed to warm to 20 and then irradiated for 3 h with the reflux condenser kept at — 35°. The mixture is fractionally distilled to give methyl pentafluoroethyl tellurium as a light-yellow liquid that is stable toward water but easily oxidized yield 63% b.p. 42°. 

The process of telomerisation of tetrafluoroethylene with trifluoromethyl iodide or pentafluoroethyl iodide is initiated by UV irradiation or by a catalyst. In the latter case the reaction is carried out under pressure and at / = 80-220 °C ... 

The free-radical addition of TFE to pentafluoroethyl iodide yields a mixture of perfluoroalkyl iodides with even-numbered fluorinated carbon chains. This is the process used to commercially manufacture the initial raw material for the fluorotelomer -based family of fluorinated substances (Fig. 3) [2, 17]. Telomeri-zation may also be used to make terminal iso- or methyl branched and/or odd number fluorinated carbon perfluoroalkyl iodides as well [2]. The process of TFE telomerization can be manipulated by controlling the process variables, reactant ratios, catalysts, etc. to obtain the desired mixture of perfluoroalkyl iodides, which can be further purified by distillation. While perfluoroalkyl iodides can be directly hydrolyzed to perfluoroalkyl carboxylate salts [29, 30], the addition of ethylene gives a more versatile synthesis intermediate, fluorotelomer iodides. These primary alkyl iodides can be transformed to alcohols, sulfonyl chlorides, olefins, thiols, (meth)acrylates, and from these into many types of fluorinated surfactants [3] (Fig. 3). The fluorotelomer-based fluorinated surfactants range includes noiuonics, anionics, cationics, amphoterics, and polymeric amphophiles. 

It was mentioned earlier that pentafluoroethyl iodide was decomposed by magnesium in ether. Nevertheless, it has been possible to prepare several perfluoroethyltin compounds (Section V, C) by adding pentafluoroethyl iodide to a mixture of alkyltin chlorides and magnesium in tetrahydrofuran at room temperature (29). Yields of the desired product can be as high as 50%. 

Several R3SnRp compounds have been made from similar reactions involving pentafluoroethyl iodide and hexaethyl- or hexaphenylditin (46). 

At present our knowledge of fluorocarbon-lead compounds is limited to (CH3)3PbCF3 and (CH3)3PbC2Fs (46). These substances can be obtained by heating at 150° C mixtures of tetramethyllead and trifluoromethyl iodide or pentafluoroethyl iodide, respectively. Considerable quantities of fluoro-form and pentafluoroethane are produced in these reactions and vapor phase chromatography was used to separate the desired lead compounds from unreacted tetramethyllead and methyl iodide. 

The starting materials of the telomerization process are tetrafluoroethylene and a perfluoroalkyl iodide. Of the various perfluoroalkyl iodides used in telomerization processes, pentafluoroethyl iodide is the most important (see Section 2.3). The one-step process for manufacturing pentafluoroethyl iodide is based on the addition of iodine fluoride to tetrafluoroethylene. Iodine fluoride, IF, is too unstable to be isolated and is therefore formed from iodine pentafluoride and iodine in situ. Iodine pentafluoride is synthesized from iodine and elemental fluorine [12] ... 

Scherer and Futterer [20] prepared pentafluoroethyl iodide by passing pentafluoroethyl bromide through a layer of KI at 500°C. 

Millauer [21-23] prepared pentafluoroethyl iodide and heptafluoropropyl iodide by a reaction of 1,2-diiodotetrafluoroethane, CF2ICF2I, with HF or of CF2CF=CF2 with iodine and HF, respectively. 1,2-Diiodotetrafluoroethane, obtained by the addition of iodine to tetrafluoroethylene, is heated in the presence of HF and a catalyst or an oxidant to form pentafluoroethyl iodide [21-24] ... 

Electrochemical synthesis of pentafluoroethyl iodide from CF2ICF2I in the presence of anhydrous hydrogen fluoride has been claimed in Hoechst patents [26]. 

Pentafluoroethyl iodide (1-iodopentafluoroethane) reacts with tetrafluoroethylene under conditions similar to those for iodotrifluoromethane and yields perfluoroalkyl iodides, CF3CF2[CF2CF2] I, with an even number of carbon atoms. 

Commercial telomerization of tetrafluoroethylene with pentafluoroethyl iodide was developed by the Du Pont Company [65,66]. The telogen, pentafluoroethyl iodide, is prepared by reacting iodine pentafluoride and iodine with tetrafluoroethylene [13,14] (see Section 2.1) ... 

Telomerization of tetrafluoroethylene with pentafluoroethyl iodide produces a mixture of even-carbon-numbered telomers differing in their overall carbon chain length ... 

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