A-fluoroacrylates

With the ready availability of 2-fluoro-allylic halides and a-fluoroacrylic acid derivatives, incorporation of a pendant fluorovinyl unit is easier than ever. The utility of these products is markedly enhanced by the reactivity of the fluorovinyl unit in olefin metathesis reactions. Some success has been found in cyclization reactions as shown below [83] (Scheme 36). 

IR Spectroscopic Analysis of Poly( lH,llT-fluoroalkyl a-fluoroacrylate) Light-Scattering Studies of Poly(ethylene-co-butylene)... 

Of a large number of possible fluorinated acrylates, the homopolymers and copolymers of fluoroalkyl acrylates and methacrylates are the most suitable for practical applications. They are used in the manufacture of plastic lightguides (optical fibers) resists water-, oil-, and dirt-repellent coatings and other advanced applications [14]. Several rather complex methods to prepare the a-fluoroalkyl monomers (e.g., a-phenyl fluoroacrylates, a-(trifluoromethyl) acrylic and its esters, esters of perfluoromethacrylic acid) exist and are discussed in some detail in [14]. Generally, a-fluoroacrylates polymerize more readily than corresponding nonfluorinated acrylates and methacrylates, mostly by free radical mechanism [15], Copolymerization of fluoroacrylates has been carried out in bulk, solution, or emulsion initiated with peroxides, azobisisobutyronitrile, or y-irradiation [16]. Fluoroalkyl methacrylates and acrylates also polymerize by anionic mechanism, but the polymerization rates are considerably slower than those of radical polymerization [17]. 

Trifuoroethyl a-fluoroacrylate Gel permeation chromatography Hydroxyethyl methacrylate... 

Table 7 Evolution of number-average degree of polymerization (DPn) with initial initiator concentration for the radical polymerization of 2,2,2-trifuoroethyl a-fluoroacrylate with tert-butylcydohexyl peroxydicarbonate at 75 °C in acetonitrile...

The development of kinetics relationships (see previously for styrene) allowed us to demonstrate that the PRT, responsible for low Mn, was not favored at all when a-fluoroacrylate was used in DEP. The kprl/k kp ratio was calculated to be about 20, whereas for styrene the ratio was calculated to be about 6 x 103. We showed that the resulting amount of PRT was about 40% for FATRIFE and about 85% (Fig. 1) for styrene for the same Co. 

The synthesis of telechelic a-fluoroacrylate with low molecular weight has not been achieved so far by using the technique of DEP. 

The preparation and characterization of the catalyst has already been explained [9]. In summary, a copolymer with an easily exchanged succinimide group was prepared by reacting a fluoroacrylate monomer (zonyl TAN, from Dupont) with N-acryloxysuccinimide (NASI) in benzotrifluoride at 100°C... 

Lopez-Castillo, Z. K. Flores, R. Kani, I. Fackler, Jr.,J. P. Akgerman, A. Fluoroacrylate Copolymer Supported Rhodium Catalysts for Hydrogenation Reactions in Supercritical Carbon Dioxide. Ind. Eng. Chem. Res., 2002,41, 3075-3080... 

Ohmori, A. Takaki, S. Kitahara, T.a-Fluoroacrylic acid esters and acid fluoride. US Patent 4,604,482, 1986. 

The chemistry of XV is similar to that of HFPO. It can be isomerized to an acyl fluoride with Lewis acids (Eq 13.16) but more importantly, it will react with nucleophiles to open the oxetane ring. Reaction with Nal yields an acyl fluoride that may be dehalogenated and esterified to give useful a-fluoroacrylate monomers (Eq 13.17). 

Some Properties of Fluorine-containing Polyalkyl(meth)acrylates and a-fluoroacrylates... 

CH2=CF-C(0)0-0CH2Q(0CF2CF2)20CF3 1,1 -dihydro-3,8,9-trioxaperf luorodecy 1-a-fluoroacrylate (FOAaFA-2) 69/2.1 1.582 1.2970... 

Polymerization Studies. Anionic Polymerization of Caprolactam (the use of (CFs C0)20 (ca. 2 mole %) enabled a lower reaction temperature to be employed and higher yiel and polyamide molecular weights to be obtained]. Soil-retardant Finishing of Cotton Ooth by Vapour-phase Graft Polymerization of Fluoroalkyl Acrylates. Radical Polymerization of a-Fluoroacrylic Acid and -Vinylpyrrolidone in an Aqueous Solution. Perfluoropolyether Esters of Quinones [the preparation of the title compounds by reaction of 1.5-dihydroxyanthraquinone with per-fluoropolyetheracyl fluorides, e.g. CFj-CFi-CF -O-CF(Ci )-CaPj-O-CF(CF,)-C50F, is... 

Various acrylic polymers and copolymers are also utilized as support materials. For instance, a copolymer of a fluoroacrylate monomers was prepared by Bergbreiter and coworkers to form a support material that is selectively soluble in fluorinated solvents [28-32],... 

CHF CFa, from hexafiuoropropene and propene at 250 °C, the formation of addacts between ethyl a>fluoroacrylate and chlorotrifluoro- or tetrailuoro-ethylene, preparation of various 1,1,2-trifluorocyclobutanes as anaesthetics, and the formation of adducts (78 X = Y = F or Cl X = F, Y = O) from diethyl itaconate at 180 °C, where diethyl dtraconate failed to react. 2-Alkoxy-3-phenylcyclobut-2-enoiies are formed when the adducts of styrene and CF tCFCl or CFgiCFj are treated with potassium hydroxide in ethanol or potassium t-butoxide in t-butanol, respectively. The adducts of / -nitro- and p-methoxy-phenylacetylene and chlorotrifluoro-ethylene may be hydrolysed by concentrated sulphuric acid to arylcyclo-butenediones. Tetrafluoroethylene adds photochemically to 3p-acetoxy-pregna-5,16-dien-20-one by [2 + 2] addition to the C—C bond of the enone grouping and by [2 + 4] addition to this function. ... 

Alternatively, the phosphine moiety has been linked to a fluoroacrylate copolymer in order to separate the strong electron-withdrawing group from the ligating phosphine unit (Scheme 2.43) [149]. For the synthesis, the... 

Scheme 2.43 Anchoring of phosphine groups to a fluoroacrylate copolymer.

Scheme 3 Asymmetric [3-1-2] cycloaddition of azomethine ylides with trani-4,4,4-trifluoro-crotonate and methyl a-fluoroacrylate...

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