Hydrophilic Quaternary Ammonium Type Ionic Liquids. Systematic Study of the Relationship among Molecular Structures, Osmotic Pressures, and Water-Solubility

Abstract

This Letter examines the relationship between the structures of ionic liquids and their water-solubility or osmotic pressure with a number of synthesized quaternary ammonium type ionic liquids and organic salts containing a hydroxyl group as hydrophilic substituted groups on ammonium group cations, and bromide or methylsulfonate as anions. The study found a linear relation between the amount and osmotic pressure of the water-soluble ionic liquids synthesized here, strongly indicating that these water-soluble ionic liquids are perfectly ionized in water like inorganic salts with small diameter ions.

SEM Observation of Wet Biological Specimens Pretreated with Room‐Temperature Ionic Liquid

“…More recently Kawai et al reported that choline-like RTILs show higher osmotic pressure than imidazolium-based RTILs. [23] This seems to support our finding that a longer immersion time is required with imidazolium-based 6 than with choline-based 2. As to the pretreatment with incompatible RTILs (for example, 3), we could not observe a clear SEM image of the active L929 cells having pseudopods.…”

“…[23] It is known that such aqueous solutions of RTILs are relatively stable under vacuum. [24] The morphology preservation of wet biological specimens under vacuum may be caused by an anomalous physical property of the RTIL aqueous solution.…”

Physicochemical and Acid-base Properties of a Series of 2-Hydroxyethylammonium-based Protic Ionic Liquids

“…[33][34][35][36][37] In order to clarify solvent natures, one must have extensive knowledge of physicochemical and Brønsted and/or Lewis acid-base properties of ionic liquids. Experimental results for the physicochemical properties [38][39][40][41][42][43][44][45][46][47][48][49][50][51][52] and solvatochromic parameters [53][54][55] of ionic liquids with the hydroxyl groups have been reported.…”

SEM observation of the live morphology of human red blood cells under high vacuum conditions using a novel RTIL

“…Recently, we synthesized a series of hydrophilic RTILs whose structures include choline‐like quaternary ammonium groups that appear to have good compatibility with biologic samples, because their structures are similar to biomaterials …”