Patent ID: 6365739
Filing Date: 2002-04-02
Classification: C07D

Abstract:
A process for the preparation of compounds of the formula (I) in which each of the radicals X and Y independently of one another is hydrogen, halogen, (C1-C4)alkyl, (C1-C4)alkoxy or (C1-C,)alkylthio, where each of the last-mentioned 3 radicals is unsubstituted or substituted by one or more radicals from the group consisting of halogen, (C1-C4)alkoxy and (C1-C4)-alkylthio, or di[(C1-C4)alkyl]amino, (C3-C6)cycloalkyl, (C3-C5)-alkenyl, (C3-C5)alkynyl, (C3-C5)alkenyloxy or (C3-C5)-alkynyloxy, which comprises reacting a compound of the formula (II) or its salts in which X and Y are defined as in formula (I), with 1 to 6 mol of phosgene per mole of compound of the formula (II), in the presence of 2 to 3.5 molar equivalents of a base per mole of compound of the formula (II) and in the presence of an aprotic organic solvent at a reaction temperature in the range from âˆ’30 to +60Â° C., to give the compound of the formula (I).