2,5-Oxazolidinone can be used as a pharmaceutical synthesis intermediate. Glycine-N-lactaloanhydride, valine-N-lactaloanhydride (2,5-Oxazolidinone), leucine-N-lactaloanhydride, or alanine-N-lactaloanhydride, these amphiphilic polyamino acids with hydrophilic and hydrophobic segments, can form nanoscale physical gels in water and can gel at certain temperatures. Therefore, these physical gels can serve as carrier materials for drug delivery and controlled release.
Phosgene was passed in a fine stream into a suspension of finely ground glycine (15 g) in dry dioxane (750 mL) at 45–50 ℃ with efficient agitation. A clear solution was obtained after 5 h. This solution was filtered to remove unreacted glycine (1.7 g), and the dioxane was then removed under reduced pressure at a temperature below 40 ℃ under exclusion of moisture. The residue was treated with dry diethyl ether (100 mL), and the crystals of 2,5-oxazolidinedione were collected by filtration and dried over P2O5 in a vacuum desiccator. The crude product thus obtained, 16 g (89%), was recrystallized from ethyl acetate/petroleum ether to yield 14.3 g (77.2%) of pure material, which showed no melting point because of polymerization.
Into a suspension of finely ground glycine (15 g) in dry dioxane (750 mL), phosgene was introduced in a fine stream at 45–50 °C with efficient agitation. A clear solution was obtained after 5 h. This solution was filtered to remove unreacted glycine (1.7 g), and the dioxane was then removed under reduced pressure at a temperature below 40 °C with protection from moisture. The residue was treated with dry diethyl ether (100 mL), and the crystals of 2,5-oxazolidinedione were collected by filtration and dried over P2O5 in a vacuum desiccator. The crude product so obtained, 16 g (89%), was recrystallized from ethyl acetate/petroleum ether to yield 14.3 g (77.2%) of pure material, which showed no melting point because of polymerization.
