Carbohydrate Based Ionic Liquids (CHILs): Synthesis and Applications

Abstract

Carbohydrate based ionic liquids (CHILs) are a sub‐class of ionic liquids which first emerged in 2007 and has since then attracted a steadily growing community of organic chemists. Since carbohydrates are naturally occurring materials with a broad spectrum of diastereomers, they are fitting materials for ionic liquids bearing stereochemical information. This review gives an up‐to‐date overview of all CHILs and their applications in asymmetric chemistry.

From Chitin to CHILs: First Glucosamine based Ionic Liquids

“…Carbohydrate-based ionic liquids (CHILs) are an uprising subclass of ionic liquids. [1,2] Like ionic liquids in general, they are salts with melting points below 100 °C, however, CHILs are specifically derived from carbohydrates and encompass an intact carbohydrate moiety.…”

“…[7] The typical synthetic strategy used by most authors is to firstly introduce a leaving group like a halogen or trifyl group into the carbohydrate, which often encompasses protection group strategies. [1] Said leaving group is then used for a quarternization reaction with amines, or N-heterocycles like imidazole or pyridine. These heterocycles however are often toxic and don't follow the general principles of green chemistry, thus contradicting the idea of CHILs as green and renewable alternatives to common ionic liquids.…”

Bioderived Ionic Liquids and Salts with Various Cyano Anions as Precursors for Doped Carbon Materials

“…In addition to the continuous search for useful biomass feedstock and ecofriendly processes suitable for its derivatization, products such as bio-derived solvents, additives, and functional materials are also of special interest. In this regard, bio-derived ionic liquids (ILs) [ 1 , 2 , 3 ] that can serve as solvents for the biomass dissolution desirable in the closed-loop biorefinery concept [ 4 ], as solvents for ionothermal biomass upgrading into functional carbon materials, or as carbon precursors themselves [ 5 , 6 , 7 ] can be useful sustainable chemicals.…”

Glucosylimidazolium Hydroxide: A Bench-Stable Carbohydrate Based Building Block

“…Ionic liquids, organic ionic molecules with a melting point below 100 • C [1], have become a well-known class of compounds since their rise in popularity in the early 1990s. While ionic liquids have since evolved into several, often task-specific, sub-classes, such as room-temperature ionic liquids (RTILs) [2], polymerized ionic liquids (PILs) [3] or magnetic ionic liquids (MILs) [4], our working group is specifically focused on carbohydrate-based ionic liquids (CHILs) [5].…”