| 摘要 |
<p>1. Claims for the contracting states : BE, CH, DE, FR, GB, IT, LI, NL New melilotic acid derivatives of the general formula : see diagramm : EP0153538,P8,F1 wherein - X represents a halogen atom - R1 is a lower alkyl radical of 1 to 4 carbon atoms, - R2 is a hydrogen atom, a metal an ammonium radical or a lower alkyl radical of 1 to 4 carbon atoms. 1. Claims for the contracting State : AT Process for preparing melilotic acid derivatives of the general formula : see diagramm : EP0153538,P9,F1 wherein X is a halogen atom, specially Cl or F, as well as salts, specially alkali metal salts, alkaline-earth metal salts, or ammonium salts, and alkyl (of 1 to 4 carbon atoms) esters of said derivatives, characterized in that it comprises the following steps : a) reaction of a halogenophenol with chloroform and an alkali so as to form a halogenophenol aldehyde according to Reimer-Tiemann reaction, b) condensation of said aldehyde with acetic acid anhydride in the presence of potassium acetate so as to form a halogenated derivative of 2-acetoxy cinnamic acid according to Perkin reaction, c) catalytic hydrogenation of the obtained acid so as to form a halogenated derivative of acetylmelilotic acid, d) optionally transformation of said acid into a salt or an ester in a known manner.</p> |
