| 摘要 |
<p>Pyrimidine-5-carboxylates of formula wherein R is C<SUB>1</SUB>-4 alkyl, R<SUP>1</SUP> is C<SUB>1</SUB>_<SUB>4 </SUB>alkyl or trifluoromethyl, R<SUP>2</SUP> is hydrogen or C1 alkyl and X is hydroxy, chlorine or bromine, are prepared from 3-oxoalkanoates of formula with urea and orthoesters of formula R<SUP>2</SUP>C(OR)<SUB>3</SUB> (III). The intermediate 2-acyl-3-ureidoacrylate, without being isolated, is reacted to give a 2-hydroxypyrimidine-5-carboxylate [(I), X = OH] or a hydrate thereof, which is optionally converted into the corresponding chloro or bromo compound (I, X = Cl, Br).</p> |
