Ionic Liquids: New Perspectives for Inorganic Synthesis?

Abstract

Ionic liquids are credited with a number of unusual properties. These include a low vapor pressure, a wide liquid-phase range, weakly coordinating properties, and a high thermal/chemical stability. These properties are certainly of great interest for inorganic synthesis and the creation of novel inorganic compounds. On the other hand, the synthesis repertoire for preparing inorganic compounds has always been broad, ranging from syntheses in solutions and melts to solid-state reactions, and from crystal growth in the gas phase to high-pressure syntheses. What new aspects can ionic liquids then add to the synthesis of inorganic compounds? This Minireview uses some early examples to show that the use of ionic liquids indeed provides access to unusual inorganic compounds.

Substitution of Conventional High-temperature Syntheses of Inorganic Compounds by Near-room-temperature Syntheses in Ionic Liquids

“…Contrary to the higher temperature method, we obtained Te 8 [34] correspond to the published data with a maximum deviation of 5σ (Table 6). [35,36].…”

[HMIM][Br9]: a Room-temperature Ionic Liquid Based on a Polybromide Anion

“…Beyond this, no structural data of a higher polybromide monoanion was known prior to our reports in recent years. Based on new synthetic strategies in either ionic liquids (ILs) [10] or in neat halogens [11] several compounds with polybromide monoanions have been prepared and were further characterized in the last two years [12]. In 2011 our group reported the first preparation and structural characterization of a higher polybromide monoanion [NPr 4 11 ] − .…”

Crystal structure of 2,6-bis(3-(pyrazin-2-yl)-1H-1,2,4-triazol-5-yl)pyridine – 1-ethyl-3-methyl-1H-imidazol-3-ium bromide (1/1), C23H22N13Br

“…Ionothermal synthesis, a method that uses an ionic liquid as solvent and structure directing agents in the preparation of crystalline solids, offers many advantages over traditional hydrothermal and solvothermal synthesis methods [5][6][7][8][9][10]. Syntheses using ILs as solvents have received increasing interest for the preparation of functional materials in the context of crystal engineering.…”