452306-41-1Relevant academic research and scientific papers
Synthesis of perfluoro- and 2-trifluoromethylpentafluoro-dihydrofurans and their epoxy derivatives
Filyakova,Kodess,Zapevalov,Saloutin
, p. 1010 - 1015 (2003)
Perfluorotetrahydrofuran-2-carboxylic acid was converted through a series of transformations into perfluoro-2,3-dihydrofuran and perfluoro-2,5- dihydrofuran; likewise, from (2-perfluorotetrahydrofuryl)difluoroacetic acid 2-trifluoromethylpentafluoro-2,3-dihydrofuran was obtained. Perfluoro-2,3- dihydrofuran and 2-trifluoromethylpentafluoro-2,3-dihydrofuran underwent isomerization into perfluoro-2,5-dihydrofuran and 2-trifluoromethylpentafluoro- 2,5-dihydrofuran by the action of cesium fluoride. Treatment of perfluoro-2,5-dihydrofuran with SbF5 resulted in ring opening and formation of cis-perfluoro-2-butenoyl fluoride, while 2- trifluoromethylpentafluoro-2,3-dihydrofuran was converted into 2-trifluoromethylpentafluoro-2,5-dihydrofuran under the same conditions. Perfluoro-3,4-epoxytetrahydrofuran and 2-trifluoromethyl-3,4-epoxypenta- fluorotetrahydrofuran containing fused oxirane and tetrahydrofuran rings were synthesized by reactions of perfluoro-2,5-dihydrofuran and 2- trifluoromethylpentafluoro-2,5-dihydrofuran, respectively, with sodium hypochlorite.
ULTRAVIOLET-PERMEABLE FLUOROPOLYMERS AND PELLICLES MADE BY USING THE SAME
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Page/Page column 16, (2008/06/13)
A pellicle which is excellent in transmittance and durability against short wavelength light, and which can be used for photolithography by using e.g. a KrF excimer laser, is provided. A pellicle for exposure to a light having a wavelength of at most 200 nm, which comprises a frame and a pellicle membrane bonded to the frame by means of an adhesive, wherein the pellicle membrane and/or the adhesive comprises a polymer containing repeating units represented by the following formula (1): wherein Q represents a C1-3 polyfluoroalkylene group having a linear structure, or a group having at least one atom selected from hydrogen atoms and fluorine atoms in such a polyfluoroalkylene group substituted by a substituent comprising a polyfluoroalkyl group which may contain an ethereal oxygen atom, or the like, and X represents a hydrogen atom, a fluorine atom or a C1-3 polyfluoroalkyl group which may contain an ethereal oxygen atom.
