PROCESS FOR THE PREPARATION OF EBERCONAZOL AND INTERMEDIATES THEREOF

摘要

The 2-[2-(3,5-dichlorophenyl)ethyl]benzoic acid (V) which is the key intermediate for the preparation of eberconazol (I) through a known sequence of four steps is prepared by catalytic hydrogenation of 2-[2-(3,5-dichlorophenyl)ethenyl]benzoic acid (VI). The intermediate (VI) is prepared by hydrolysis of its methyl ester obtained by a Wittig reaction between 3,5-dichlorobenzaldehyde and the ylure of phosphor of the bromide of [[(2-metoxycarbonyl)phenyl]-methyl]triphenylphosphonium. The global process can be easily increased in scale since the reactions can be carried out at moderate temperature without requiring a strictly inert atmosphere and without any risk of inflammation. The carboxylic acid (VI) and its methyl ester are chemically new intermediates. The invention is useful for the industrial preparation of the antifongic agent eberconazol (I).