| 摘要 |
A process for the preparation of 2-amino-4-fluoropyrimidine derivatives of the general formula I <IMAGE> I (R1 hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, phenyl or benzyl, it being possible for the aromatic rings to be substituted, and R2 one of the R1 radicals with the exception of hydrogen) by reaction of 2,4,6-trifluoropyrimidine in an aprotic polar organic solvent with an amine of the formula III to give the 2-aminodifluoropyrimidine derivative IVa mixed with the 4-aminodifluoropyrimidine derivative IVb, separation of IVa out of the resulting reaction mixture and subsequent reaction of IVa with an alcohol in the presence of a base at from 0 DEG to 180 DEG C. to give the 2-amino-4-fluoropyrimidine derivative I, by carrying out the reaction of 2,4,6,-trifluoropyrimidine II with the amine III at from -80 DEG C. to -15 DEG C., and reacting the 2-aminodifluoropyrimidine derivative IVa with the alcohol in the presence of an organic base to give the 2-amino-4-fluoropyrimidine derivative I.
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