Synthesis and Applications of Ionic Liquids Derived from Natural Sugars

摘要: Aiming to develop environmentally compatible chemical syntheses, the replacement of traditional organic solvents with ionic liquids (ILs) has attracted considerable attention. ILs are special molten salts melting points below 100°C that typically constituted cations (imidazolium, pyridinium, sulfonium, phosphonium, etc.) and inorganic anions. Due their nature, they endowed high thermal stability, good solvent properties, non-measurable vapor pressure. Although recovery unaltered recycling partly compensate rather cost, it is important new synthetic approaches less expensive sustainable based on renewable raw materials. In fact, most these alternative still prepared starting from fossil feedstocks. Until now, only a limited number have been sources. Surprisingly, available inexpensive material, i.e., carbohydrates, hardly exploited in synthesis ILs. 2003 imidazolium-based were d-fructose used as Mizoroki–Heck Diels–Alder reactions. Later on, first chiral derived sugars methyl d-glucopyranoside. same year, family ILs, obtained commercial isosorbide (dianhydro-d-glucitol), was described. A closely related approach followed by other researchers synthesize mono- bis-ammonium isomannide (dianhydro-d-mannitol). Finally, few bearing pentofuranose unit moiety using sugar phosphates glycosyl donors 1-methylimidazole acceptor.