Process for producing oxazolidin-2-one derivative

A process for preparing an oxazolidin-2-one derivative represented by the following general formula (3a):

• wherein R11, R21, R31 and R41 are hydrogen atom, C1-C4 lower alkyl group, methoxymethyl group, benzyloxymethyl group or benzyl group and R51 is hydrogen atom, C1-C4 lower alkyl group, benzyl group, phenyl group, cyanophenyl group, naphthyl group or thienyl group, which comprises reacting a 1,3-dioxolan-2-one derivative represented by the following general formula (1a):
• wherein R11, R21, R31 and R41 are the same as defined above, and a carbamate derivative or an urea derivative represented by the following general formula (2a):
• R5HNCOX1 (2a)
• wherein R51 is the same as defined above, X1 is OR61 or NR71R81 in which R61 is C1-C4 lower alkyl group or phenyl group, R71 and R81 are the same as R51,
• in the present of a fluoride salt in a solvent of N, N-dimethylformamide or dimethyl sulfoxide.

A process for preparing an oxazolidin-2-one derivative represented by the following general formula (3):

• wherein R1, R2, R3 and R4 are hydrogen atom, straight, branched or cyclic alkyl group, straight or branched alkyl group substituted by alkoxy, substituted amino or alkylthio, substituted or unsubstituted aralkyl group, or substituted or unsubstituted aryl group, and R5 is hydrogen atom, straight, branched or cyclic alkyl group, substituted or unsubstituted aralkyl group, or substituted or unsubstituted aromatic ring, which comprises reacting a 1,3-dioxolan-2-one derivative represented by the following general formula (1):
• wherein R1, R2, R3 and R4 are the same as defined above, and a carbamate derivative or an urea derivative represented by the following formula (2):
• R5HNCOX (2)
• wherein R5 is the same as defined above, X is OR6 or NR7R8 in which R6 is lower alkyl, or substituted or unsubstituted aryl, and R7 and R8 are independently the same as R5,
• in the presence of an alkyl metal fluoride or an alkaline earth metal fluoride.