Synthesis of thiacalix[4]arene task-specific ionic liquids

GRAPHICAL ABSTRACT

ABSTRACT

The preparative methods for the synthesis of imidazolium and pyridinium room temperature task-specific ionic liquids possessing thiacalix[4]arene complexing groups in cationic or anionic fragments of the molecule are described. The cationic imidazolium and pyridinium derivatives of tetrabuthoxythiacalixarene existing in the conformation 1,3-alternate are capable to bind “soft” metal cations due to cooperative cation-π and ion–dipole interactions with spatially contiguous benzene rings and oxygen atoms of the thiacalixarene platform. The cone-shaped imidazolium salts of the tetrahydroxythiacalix[4]arene sulfonic acid can chelate cations of transition metals, lanthanides, and actinides by oxygen and sulfur atoms at the lower rim of macrocycle.

Keywords:

• Thiacalixarenes
• ionic liquids
• imidazolium salts
• complexation

Additional information

Funding

This work was supported by the National Academy of Sciences of Ukraine. The molecular calculation was performed using computational facilities of joint computational cluster of the Institute of Single Crystals of the National Academy of Science of Ukraine incorporated into the Ukrainian National Grid.