Crystal Structure and Thermal Property of 1-Ethyl Acetate Pyridinium Ionic Liquid

摘要

[EAPy][PF_6] Pyridinium ionic liquid was synthesized by two-step process: introduction of one ethyl acetate group and anions metathesis. Additionally, single crystals of the IL was first obtained by solvent-evaporation method in growth systems. [EAPy][PF_6] crystallizes in the monoclinic space group C2/c, with unit cell parameters a =22.748 A, b =6.204 A, c =18.552 A, β =92.66°, z =8,V=2615(3) A, Dc =1.58 Mg/m~3 and F(000)=1264. In its supramolecular structure, the double zigzag chains are formed by hydrogen bonds and these [P(1)F_6]~- and [P(2)F_6]~- anions are sandwiched respectively by pyridinium rings and ethyl acetate groups in the packing pattern. Moreover, [EAPy][PF_6] exhibits relatively high thermal stability and obvious supercooling during the cooling process, which makes pyridinium IL difficult to crystallize.