Process for the preparation of pyrimidine derivatives
AssigneeCiba-Geigy Corporation
InventorsGottfried Seifert, Robert Hassig
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Abstract
4,6-Bis(difluoromethoxy)pyrimidines of formula I ##STR1## wherein R is C.sub.1 -C.sub.4 alkyl or unsubstituted or substituted phenyl or benzyl, are prepared by reacting a 4,6-dihydroxypyrimidine dialkali metal salt of formula II ##STR2## wherein R is as defined for formula I and Me is an alkali metal, with chlorodifluoromethane in a solvent selected from the group consisting of ketones and alkyl cyanides, in the presence of 0.05 to 1.1 mol of water per mol of dialkali metal salt of formula II.
Claims21
A process for the preparation of a 4,6-bis(difluoromethoxy)pyrimidine of formula I ##STR5## wherein R is C.sub.1 -C.sub.4 alkyl, phenyl or benzyl, which process comprises reacting a 4,6-dihydroxypyrimidine dialkali metal salt of formula II ##STR6## wherein R is as defined for formula I and Me is an alkali metal, with chlorodifluoromethane in a solvent selected from the group consisting of ketones and alkyl cyanides, in the presence of 0.05 to 1.1 mol of water per mol of dialkali metal salt of formula II.
Dependencies are inferred from the claim text.