- Process for the preparation of 4-chloro-5-alkoxycarbonyl-2-methoxy-pyrimidines
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Process for the preparation of a 4-chloro-5-alkoxycarbonyl-2-methoxy-pyrimidine of the formula: STR1 IN WHICH R1 is a lower alkyl radical with 1 to 4 carbon atoms, which comprises the following stages: A) condensation of a salt of O-methylisourea and an inorganic or organic acid, with an alkyl alkoxymethylenemalonate STR2 in an aqueous medium and in the presence of an excess of an alkali metal hydroxide, to form the corresponding salt of the 5-alkoxycarbonyl-4-hydroxy-2-methoxy-pyrimidine, and neutralization of the said salt by the addition of an inorganic or organic acid, in order to liberate this 5-alkoxycarbonyl-4-hydroxy-2-methoxy-pyrimidine, and STR3 B) bringing the latter compound, suspended in dimethylformamide, into contact with thionyl chloride, at room temperature, in order to form the corresponding 4-chloro-5-alkoxycarbonyl-2-methoxy-pyrimidine: STR4
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