Cavallo Gabriella, Abate Antonio, Rosati Marta, Paolo Venuti Giovanni, Pilati Tullio, Terraneo Giancarlo, Resnati Giuseppe, Metrangolo Pierangelo
Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Via L. Mancinelli 7, 20131, Milano, Italy.
Helmholtz-Zentrum Berlin für Materialien und Energie, Kekuléstraße 5, 12489, Berlin, Germany.
Chempluschem. 2021 Mar;86(3):469-474. doi: 10.1002/cplu.202100046.
We report halogen-bonded complexes between 1-polyfluoroalkyl-3-alkylimidazolium iodides and mono-iodoperfluoroalkanes of different chain lengths or di-iodoperfluorooctane. F NMR analyses revealed that the preferred stoichiometry between the donors and acceptors is 1 : 1 in the cases of the mono-iodoperfluoroalkanes, and 2 : 1 with di-iodoperfluorooctane, as a result of the monodentate behavior of the iodide anion (halogen bond acceptor). Single crystal X-ray diffraction analyses showed the presence of a perfluorinated superanion, which interdigitates with the cation fluorinated chains, favoring the formation of lamellar structures. All of the obtained supramolecular complexes exhibit enantiotropic liquid crystalline phases over a broad range of temperatures. Most of the obtained complexes show melting points lower than 100 °C, two of them being liquid at room temperature, thus representing a new family of fluorinated ionic liquid crystals.
我们报道了1-多氟烷基-3-烷基咪唑鎓碘化物与不同链长的单碘全氟烷烃或二碘全氟辛烷之间的卤素键合配合物。氟核磁共振分析表明，在单碘全氟烷烃的情况下，供体与受体之间的优选化学计量比为1∶1，而与二碘全氟辛烷的化学计量比为2∶1，这是由于碘阴离子（卤素键受体）的单齿行为所致。单晶X射线衍射分析表明存在全氟超阴离子，它与阳离子氟化链相互交错，有利于层状结构的形成。所有得到的超分子配合物在很宽的温度范围内都表现出互变液晶相。大多数得到的配合物熔点低于100℃，其中两种在室温下为液体，因此代表了一类新的氟化离子液晶。
