Process for the preparation of optically active 2-(4-(aryloxy)-phenoxy) propionate herbicides

摘要

One of the routes to prepare optically active 2-(4-aryloxphenoxy)propionic acid ester herbicide is to couple optically active 2-(4-hydrophenoxy)propionic acid esters with halogenated aromatic or heteroaromatic compound. Conversion of the optically active 2-(4-hydroxyphenoxy)propionic acid ester into the acid salt prior to the coupling step effectively prevents the racemization that unexpectedly occurs otherwise.