A method for the production of chinoloncarbonsaeureestern

摘要

A process for the preparation of quinolone-carboxylic acid esters of the formulae I and II IMAGE (I) IMAGE (II) in which A represents nitrogen or =C-R4, R4 represents hydrogen, fluorine, chlorine, nitro or methyl, B represents halogen, nitro, alkoxy, alkylsulphonyloxy or the radical IMAGE and B additionally represents IMAGE if R1 does not denote cyclopropyl, and R5 represents a branched or unbranched alkyl group which has 1 to 4 carbon atoms and which can optionally be substituted by a hydroxyl or methoxy group, R6 represents hydrogen, methyl or phenyl, R7 represents hydrogen or methyl, R8 represents dialkylamino having 1 or 2 carbon atoms in the alkyl group or dialkylaminomethyl having 1 or 2 carbon atoms in the alkyl group, or aminomethyl R1 represents hydrogen, optionally substituted alkyl having 1 to 3 carbon atoms, optionally substituted cycloalkyl, 2-fluoroethyl, vinyl, methoxy or 4-fluorophenyl, R2 represents optionally substituted alkyl having 1 to 6 carbon atoms and also cyclohexyl and benzyl, R3 represents hydrogen, methyl or ethyl, and Z represents oxygen, nitrogen which is substituted by methyl or phenyl, and =CH2, characterized in that quinolonecarboxylic acids of the formulae III and IV IMAGE (III) IMAGE (IV) in which A, B, Z, R1 and R3 have the meanings indicated above, are reacted with chloroformic acid esters of the formula V Cl-COOR2 (V) in which R2 has the meaning indicated above.