Process for the preparation of 3-phenyl-5-substituted-4(1H)pyridones, and their use

摘要

3-Phenyl-5-substituted-4(1H)pyridones of the formula I <IMAGE> are prepared by reacting a compound of the formula IV <IMAGE> with a compound of the formula RNH2 or with an acid addition salt of this compound. By reacting the pyridones of the formula I with phosphorus pentasulphide, the corresponding pyridothiones are obtained. The pyridones, the corresponding pyridothiones and the salts thereof are used as the active component of herbicides. They possess a herbicidal activity against an unusually broad spectrum of weeds.