Selective Mg Insertion into Substituted Mono- and Dichloro Arenes in the Presence of Licl: A New Preparation of Boscalid

The LiCl-mediated Mg insertion into polysubstituted aryl chlorides bearing up to three chloro substituents in ortho or meta position selectively leads to Grignard reagents which readily react with various electrophiles. As an application, we have developed a new formal synthesis of boscalid.