Der Einfluß von Atropisomerie und chiralem Zentrum auf die biologische Aktivität des Metolachlor / The Influence of Atropisomerism and Chiral Centre on the Biological Activity of Metolachlor

Abstract

The four stereoisomers of the grass herbicide Metolachlor, the isomerism of which is based on a combination of a chiral centre and a chiral axis, were prepared, and their absolute configurations determined by X-ray analysis. The synthesis was achieved by using optically active starting materials and new optically active carbamates as intermediates. The herbicidal activity is mainly influenced by the chiral centre, the S-isomers being the most active ones.