Perfluorooctanesulfonyl fluorides

ECF is successfully used on a commercial scale to produce certain perfluoroacyl fluorides, perfluoroalkylsulfonyl fluorides, perfluoroalkyl ethers, and perfluoroalkylamines. The perfluoroacyl fluorides and perfluoroalkylsulfonyl fluorides can be hydrolyzed to form the corresponding acid and acid derivatives. Examples include perfluorooctanoyl fluoride [335-66-0] perfluorooctanoic acid [335-67-1] perfluorooctanesulfonyl fluoride [307-35-7] perfluorooctanesulfonic acid [763-23-1] and tris(perfluoro- -butyl)amine [311-89-7]. 

Yields of sulfonyl fluorides prepared by ECF vary depending on the particular stmcture. Chain degradation becomes more important as the chain length kicreases (6). Yields can vary from 96% for perfluoromethanesulfonyl fluoride (7) to 43—50% for perfluorooctanesulfonyl fluoride (8). Trifluoromethanesulfonic acid can be prepared via trifluoromethanesulfenyl chloride as shown ki equations 5—7 (9). 

Zhang and coworkers have reported on a palladium-catalyzed carbon-sulfur cross-coupling of aryl perfluoroalkoxysulfonates with thiols (Scheme 7.78) [91]. The fluorous substrates were obtained from commercially available phenols by treatment with perfluorooctanesulfonyl fluoride (C8F17S02F) under basic conditions. Various thiols were reacted with a slight excess of the perfluorinated sulfonates in a... 

Other aryl fluoroalkanesulfonates besides trifluoromethanesulfonyl esters of phenols can be reduced to arenes. Moreover, the preparation of such esters and their reduction may be carried out in one pot . A mixture of m-methoxyphenol, perfluorooctanesulfonyl fluoride, triethylamine, dimethylformamide, for-... 

Representative Chemicals Perfluorooctane sulfonic acid (PEGS) Perfluorooctanesulfonyl fluoride (POES) N-Methylperfluorooctane sulfonami-doethanol (N-MeFOSE) N-Ethylperfluorooctane sulfonamidoethanol (N-EtFOSE)... 

Chemical Abstracts Service Registry Numbers Perfluorooctanesulfonate, acid (CAS 1763-23-1) Perfluorooctanesulfonyl fluoride (CAS 307-35-7) N-Methylperfluorooctane sulfonamidoethanol (CAS 24448-09-7) N-Ethylperfluorooctanesulfo-namidoethanol (CAS 1691-99-2)... 

Perfluorooctanesulfonyl fluoride, intermediate for preparation of monomers and surfactants for textile treatment, paper sizes, inert fluids. Liquid mp = -1° bp = 154-155° d = 1.8240. 3M. 

Perfluorooctanesulfonyl fluoride CAS 307-35-7 EINECS/ELINCS 206-200-6 Classification Nonaromatic sulfur-oxygen compd. Empirical C8F18O2S... 

Methyidiethanolamine intermediate, surfactants hair care Methyidiethanolamine intermediate, surfactants inert fluids Perfluorooctanesulfonyl fluoride intermediate, surfactants laundry C20-24 alpha olefin Octadecene-1 intermediate, surfactants paper sizes Perfluorooctanesulfonyl fluoride intermediate, surfactants personal care C20-24 alpha olefin Octadecene-1 intermediate, surfactants textile treatment Perfluorooctanesulfonyl fluoride intermediate, synthesis Bromodichloromethane PCA Sodium PCA Tallow amine Tetraaza-12-crown-4-tetrahydrochloride intermediate, synthetic caffeine Chloroacetic acid intermediate, synthetic drying oils Isooctyl alcohol... 

Perfluorooctanesulfonyl fluoride Specialty Chemicals Source Book-Third Edition... 

In the past years, elucidation of transformation products of per- and polyfluorinated compounds (PFC) has been a task frequently approached by analytical chemists. It has been estimated that biotransformation contributes to approximately 0.1-5% with respect to perfluorocarboxylic acid (PFCA) historical global emissions [1]. For perfluorooctanesulfonyl fluoride (POSF)-based compounds such as perfluorooctane sulfonic acid (PFOS), biotransformation products probably affect environmental burden marginally, although no distinct estimations have been made so far [2]. 

As shown in Figure 18.2, the majority of the perfluorooctanesulfonyl fluoride was converted onsite by the 3M Company through the sulfonamide into A-methyl or A-ethyl perfluorooctanesulfon-amidoethanol. These two compounds (and most of the other intermediates shown in Figure 18.2) were primarily used as intermediates for the preparation of fluoropolymers in protective treatments for carpets, upholstery, apparel, and leather products. Several of the other compounds derived from perfluorooctanesulfonyl fluoride were used for the production of surfactants. For example, the... 

FIGURE 18.2 Chemical end use of perfluorooctanesulfonyl fluoride produced by the 3M Company as a consumed intermediate for the production of other chemicals. (Based on 3M Company, Voluntary use and exposure information profile perfluorooctanesulfonyl fluoride (PEGS). U.S. EPA Administrative Record AR226-0576, U.S. EPA, Washington, EX , 2000.)... 

As mentioned earlier, perfluorooctanesulfonyl fluoride and its homologues are prepared by electrochemical fluorination of organic compounds. " During the process, which was invented by Simons, the corresponding hydrocarbon sulfonyl fluoride or chloride is fluorinated in anhydrous HF by applying a direct electrical current with a voltage typically between 5 and 7 The elec-... 

As a result of the side reactions, industrial perfluorooctanesulfonyl fluorides are complex mixtures containing only approximately 70% of the n-perfluorooctanesulfonyl compound. These mixtures are typically not purified before use for the production of fluorinated surfactants. Because of the similar boiling points, it is not feasible to separate linear perfluorooctanesulfonyl fluoride from its branched analogues by fractional distillation however, it is possible to obtain pure linear perfluorooctanesulfonyl fluorides by fractional crystallization at -20°C. ... 

The yield of the electrochemical fluorination can reportedly be improved by the addition of butadiene sulfones. ° This additive is highly soluble in anhydrous HF and increases the conductivity of the electrolyte solution. Butadiene sulfone itself is fluorinated to perfluorobutanesulfonyl fluoride and, therefore, needs to be added continuously to the reaction. The use of this additive increases the yield of perfluorooctanesulfonyl fluoride by -10% It may act by trapping radicals formed at the anode, but the mechanism by which it increases the yield of the electrochemical fluorination of long-chain sulfonic acid derivatives is unknown. 

Perfluoroalkanesulfonic acid salts (e.g., potassium, lithium, ammonium, and diethanol ammonium salts) are useful surfactants and are prepared by the hydrolysis of the fluoride as shown in Scheme 18.1. Long-chain perfluoroalkanesulfonyl fluorides are only slowly hydrolyzed by water. For example, perfluorooctanesulfonyl fluoride is minimally hydrolyzed by water at 180°C, even... 

A challenge for industrial syntheses of perfluoroalkanesulfonate tetraalkylammonium salts is the impurities present in technical perfluorooctanesulfonyl fluoride. These impurities cause side reactions that result in tar formation, thus lowering the production yield. One patent claims the preparation of the desired perfluoroalkanesulfonate tetraalkylammonium salts in excellent yields and good purities by reaction of the sulfonyl fluoride with alkoxysilanes (e.g., triethoxymethylsilane) and trial-kylamines (e.g., triethylamine) in a suitable organic solvent (e.g., chlorobenzene, ether, or toluene) as outlined in Scheme 18.1. Under these conditions, the ammonium salts crystallize from the reaction mixture, whereas the fluorosilane by-products remain dissolved in the organic solvent. 

As outlined in Figures 18.1 and 18.2, perfluoroalkanesulfonyl fluorides, especially perfluorooctanesulfonyl fluoride, are industrial intermediates that are converted into the corresponding sul-fonamides. These sulfonamide intermediates are ultimately converted into a whole host of fluorinated surfactants, but have also been used in large quantities for the preparation of surface treatments or paper protectants. The following sections discuss important aspects of the synthesis of perfluoroalkanesulfonamides followed by an overview over the synthesis of selected perfluoroalkanesulfonyl surfactants (Section 18.2.4). 

M Company, Voluntary use and exposure information profile perfluorooctanesulfonyl fluoride (PFOS). U.S. EPA Administrative Record AR226-0576, U.S. EPA, Washington, DC, 2000. 

Perfluorooctanesulfonyl fluoride Octanoic acid n-Octanoic acid. See Caprylic acid Octanoic acid, aluminum salt. See Aluminum caprylate Octanoic acid, ammonium salt. See Ammonium caprylate Octanoic acid calcium salt. See Calcium caprylate Octanoic acid, diester with 1,2,3-propanetriol. See Glyceryl dicaprylate Octanoic acid, 2,2-dimethyM, 3-propanediol diester. See Neopentyl glycol dio-ctanoate... 

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