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Updated: Dec 4, 2025
Synthesis of Esters Via a Greener Steglich Esterification in Acetonitrile
Published on: October 30, 2018
Ethanol-free antisolvent crystallization of glycine by liquefied dimethyl ether
Hideki Kanda1,2,3, Tsubasa Katsube1, Rintaro Hoshino1
1Department of Materials Process Engineering, Nagoya University, Furocho, Chikusa, Nagoya, 464-8603, Japan.
Abstract:
Liquefied dimethyl ether (DME) was employed as an antisolvent to crystallize glycine from its aqueous solution. The proposed method can be performed at 20-25 °C and has the potential to reduce the energy consumption of drying or crystallizing using ethanol. α-Glycine crystals were successfully obtained from glycine aqueous solutions by mixing in liquefied DME, which was easily removed from the crystals by decompression. Contact with a liquefied DME/water mixture and small γ-glycine crystals resulted in the α-glycine converting to γ-glycine. This was only observed for saturated glycine solutions. We speculated that this conversion occurs via a solution-mediated transition. Pure liquefied DME is not capable of promoting solvent-mediated transitions, so saturated glycine solutions treated with the pure antisolvent can give α-glycine as the sole product.
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