Tetrafluorothiophene S,S-Dioxide: A Perfluorinated Building Block
摘要:
Tetrafluorothiophene S,S-dioxide, a highly reactive diene and dienophile, has been synthesized. A new route to 3,4-difluoro- and tetrafluorothiophene has been realized, and the previously unknown 2,3,4-trifluorothiophene has been obtained. The reactivity of tetrafluorothiophene S-oxide has been compared with that of the S,S-dioxide.
四氟噻吩是通过熔融碱将3 H / 4 H-六氟噻喃脱氟而制得的。与四氟呋喃不同,它不与溴反应,也不迅速聚合。如另一种可能的异构体2,3,5-三氟-4-甲氧基噻吩的独立合成所证明,它与甲醇钠反应生成2-氟取代。还已经制备了2,5-二氟噻吩和2,5-二氟-3-甲氧基噻吩。甲氧基噻吩均迅速聚合。在多氟噻吩的19 F nmr光谱中,α-氟共振到β的高场。同样,2–5 F–F耦合较大(26–31 Hz)。