726-05-6Relevant articles and documents
The Synthesis and Characterization of Highly Fluorinated Aromatic Polyimides
Simone, Christopher D.,Vaccaro, Eleonora,Scola, Daniel A.
, p. 100 - 112 (2019)
The synthesis and characterization of pendant octafluoro aromatic polyimides (8 F-PIs) derived from 4, 4’-(2, 2, 2-trifluoro-1-pentafluorophenylethylidene)diphthalic anhydride (8 FDA) and several aromatic diamines is described. The synthesis of bis(3,4-dimethylphenyl)pentafluorophenyltrifluoromethylmethane (8 FTM), and 2-(3, 4-dimethylphenyl)-2-pentafluorophenyl-2-trifluoromethylethanol (8 F-OH), the precursors to 8 FDA are also discussed. The synthesis of 8 FTM is accompanied by two major by-products resulting in a low yield of desired product. The presence of the pentafluorophenyl group in the backbone of the fluorinated polyimides introduces flexibility and free volume manifested by lower Tg's than more rigid analogs. The highly fluorinated polyimides exhibited lower dielectric constants than most fluorinated polyimides. The 8 F-PIs cured at a maximum temperature 371 °C/1 hr. exhibited thermal stabilities typical of high performance fluorinated polyimides. High temperature (436 °C) and pressure (281.2 kg/m2, 4000 psi.) post cure of 8 F-PI prepared from 8 FDA and p-phenylene diamine exhibited high thermo-oxidative stability, high density and low moisture absorption.
Functional Ionic Liquids as Efficient and Recyclable Catalysts for the Methylation of Formaldehyde with Aromatics
Song, Heyuan,Jin, Fuxiang,Jin, Ronghua,Kang, Meirong,Li, Zhen,Chen, Jing
, p. 1264 - 1272 (2016/07/06)
Abstract: Methylation of formaldehyde with various aromatics under functional ionic liquids catalysis has been developed. Among the ionic liquids investigated, triphenyl-(4-sulfobutyl)-phosphonium triflate ([TTPBs][CF3SO3]) showed high activity and afforded excellent yields of diarylmethane derivatives. A mechanism for the catalytic performance of [TTPBs][CF3SO3] is proposed. Besides, the catalyst can simply be separated from the reaction mixture by centrifugation and be recycled ten times without noticeable loss of activity. Graphical Abstract: Diarylmethane derivatives were successfully synthesized from the methylation of formaldehyde with aromatics using efficient and recyclable functional ionic liquids as catalysts, excellent yields and selectivities were obtained under solvent free conditions. The catalyst was reused at least ten consecutive recycles without noticeable loss in its catalytic activity. Meanwhile, the usability of catalyst was explored.[Figure not available: see fulltext.]
PROCESS OF PRODUCING 1,1 DIARYL ALKANES AND DERIVATIVES THEREOF
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Page/Page column 2, (2011/08/03)
A process of producing a 1,1-diaryl alkane comprising a condensation reaction of an aromatic compound having at least one aromatic hydrogen with an acetal, in the presence of a perfluorinated sulfonic acid in polymeric form as catalyst.
Structural requirements for decarbonylative α,α-diarylation reaction of 2-methoxyalkanoic acids in phosphorus pentoxide-methanesulfonic acid mixture yielding 1,1-diarylalkane homologs
Yonezawa, Noriyuki,Hino, Tetsuo,Tokita, Yoshimi,Matsuda, Kazuhisa,Ikeda, Tomiki
, p. 14287 - 14296 (2007/10/03)
2-Methoxyalkanoic acids were found to undergo consecutive decarbonylative α,α-diarylation in P2O5-MsOH instead of Friedel-Crafts type arylation on the carbonyl carbon. The influence of the substituents of the arenes and the carboxylic acids in this reaction was elucidated based on the reaction yields. The reaction behavior was found to be primarily governed by the electron-withdrawing/releasing property of the α-substituents on the carboxylic acids as well as the positive species-accepting ability of the arenes. The steric hindrance was shown to participate in determining the reaction feasibility as a secondary factor.
