HERBICIDAL ACTIVE UNSATURATED ESTERS OF 4- (3',5'-DIHALOGENPYRIDYL-(2')-OXY)-ALPHA-PHENOXY PROPIONIC ACIDS, PROCESS FOR THEIR PREPARATION, HERBICIDAL COMPOSITIONS CONTAINING THEM AND THEIR USE

摘要

A class of herbicidal unsaturated esters of alpha -[4-(3',5'-dihalogeno-pyridyl-2'-oxy)-phenoxy]-propionic and -thiolpropionic acid of the formula IMAGE wherein Hal is chlorine or bromine, X is oxygen or sulfur, and R is an unsubstituted or halogenated aliphatic or alicyclic radical which may contain nitrogen, and which possesses at least one double and/or triple bond, with the proviso that if X is oxygen, R is not an unsubstituted alkenyl radical. These new esters are useful for selective post-emergent control of grassy weeds in cultivated plants such as wheat, barley, rice and soybean.