Development of an novel synthetic method for the preparation of ultra-resistant perfluorinated rubber

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K05234
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 35020:Polymer materials-related
• Research Institution: Kyoto Institute of Technology
• Principal Investigator: Konno Tsutomu 京都工芸繊維大学, 分子化学系, 教授 (70303930)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: [2+2+2]環化付加反応 / ニトリル / コバルト触媒 / 含フッ素アルキン / ピリジン環 / イソキノリノン環 / イソキノリン環 / インデノール環

Outline of Final Research Achievements

In order to improve the degradation resistance derived from the fragility of the crosslinked structure, some attempts were made to develop ultra-resistant fluoroelastomers through the [2+2+2] cycloaddition reaction using commercially available perfluoropolymers with cyano groups in the crosslinking sites, and crosslinking agents with triple bonds at both terminals.
The [2+2+2] cycloaddition reactions using various fluoroalkylated diynes and nitriles, as a model reaction for the crosslinking reaction, proceeded very smoothly in the presence of readily prepared and inexpensive cobalt catalysts. Taking advantage of the strong interaction, that is to say, pai-back donation, between the cobalt and the alkyne, which is derived from a strong electron-withdrawing fluoroalkyl substituent, various cycloaddition reactions using fluorinated alkynes to produce isoquinolinone, isnoquinoline, and indenol derivatives were also developed.

Free Research Field

有機フッ素化学

Academic Significance and Societal Importance of the Research Achievements

遷移金属を用いた含フッ素アルキンの反応では，これまでPd, Ru, Rhなどの希少かつ高価な遷移金属が利用されてきた。本研究では，自然界に豊富に存在し，かつ安価なコバルトを用い，上記遷移金属とは異なる化学的挙動，例えば，高位置あるいは高立体選択性などを実現できたことは，学術的観点から極めて貴重と言える。
また，含フッ素アルキンとニトリルとの交差[2+2+2]環化付加反応を開発できたことは，今後の反応条件の更なる精査が必須であるとはいえ，ペルフルオロゴム原料を用いた交差[2+2+2]環化付加反応を通じた，超耐性フッ素ゴム創製の実行可能性に光明が差したと言え，社会的意義も大きいと思われる。