This invention relates to a novel process for the preparation of 2-oxazolidinones.
2-Oxazolidinones are useful as intermediates in the preparation of drugs, and polymers of 2-oxazolidinones are used, for example, in preparation of fibers, tablet coatings, lubricant additives, cigarette filters, rust inhibitors and dyeing assistants.
Many conventional processes for preparing 2-oxazolidinone and its derivatives are known. 2-Oxazolidinone may be prepared by any one of the reactions shown as follows:
the reaction of .beta.-aminoalcohol with a compound selected from the group consisting of phosgene, dialkyl carbonate, carbon dioxide, urea, isocyanate, ethylchlorocarbonate, and carbon disulfide;
the reactions of epoxide with a compound selected from the group consisting of cyanuric acid, urea and cyanamide;
the reaction of aziridine compounds with carbon dioxide;
the reaction of acrolein with isocyanate; or the removal of hydrochloric acid from .beta.-hydroxyalkyl semicarbazide.
However, such conventional processes have several disadvantages; for example, high cost of starting raw materials, complexity of the procedure, high toxicity of reactants or low yield of 2-oxazolidinone and its derivatives.
What is needed is a relatively simple process for the preparation of 2-oxazolidinones in high yields.
USPTO Backgrounds
USPTO Backgrounds