Synthesis of a cellulose dissolving liquid zwitterion from general and low-cost reagents

A carboxylate-type liquid zwitterion, OE₂imC₃C, has been recently reported as a unique solvent as a class of ionic liquids with distinctive properties and functions such as cellulose dissolution ability and low toxicity to fermentative microoganisms. Therefore, OE₂imC₃C first enabled successive conversion of biomass to bioethanol in the same reaction pot. However, the reagent, 1-bromo-2-(2-methoxyethoxy)ethane, used for OE₂imC₃C synthesis is expensive and sometimes out of production and thus prevents its industrialization. Here we synthesized OE₂imC₃C from general and low-cost reagents. We also confirmed that the present OE₂imC₃C maintained the distinctive properties and functions because previous literature indicates synthetic procedures affect the properties. The low toxicity and cellulose dissolution ability of the OE₂imC₃C synthesized in this study were equivalent to those of conventional OE₂imC₃C. In addition, OE₂imC₃C is known to have ability to cryopreserve mammalian cells and the OE₂imC₃C synthesized in this study exhibited the ability.