Unsymmetrical bis(anilido)xanthene ligands: development and use in the preparation of magnesium diamide complexes

Unsymmetrical bis(anilido)xanthene ligands, decorated by a 2,4,6-tricyclohexylanilido substituent and a less bulky anilido group, are readily prepared in moderate yields from a 4,5-dibromo-substituted xanthene. These ligands are used for the preparation of magnesium(II) complexes, the reductions of which in methylcyclohexane and benzene are described.