Method for the preparation of 3-phenyl-5-substituted-4(1H)-pyridones
申请人:Eli Lilly and Company
公开号:US04127581A1
公开(公告)日:1978-11-28
A class of herbicidal 3-phenyl-5-substituted-4(1H)-pyridones are prepared from .beta.-aminostyrenes by reaction with bromoacetyl bromide to form an .alpha.-bromoacetyl-.beta.-aminostyrene which is reacted with an anion to form a .alpha.-substituted acetyl-.beta.-aminostyrene which is then cyclized to the pyridone by formylation and reaction with a primary amine.
A class of 3-phenyl-4(1H)-pyridones and pyridinethiones are broad-spectrum herbicides. The new compounds are characterized by a small substituent on the nitrogen, and usually bear a 5-substituent chosen from a class described herein. The phenyl ring may be substituted. The compounds are effective herbicides when applied both before and after the emergence of weeds, and are particularly useful for the control of weeds in cotton and rice cropland.