CONICET | Buscador de Institutos y Recursos Humanos

New simple phosphite, phosphonite and phosphonate chiral ligands derived from DIMPTH(OH)2 and rigid bis-DIMPTH(OH)2 were prepared with moderate to good yields (35-86%) from readily available starting materials. The syntheses of the new chiral ligands required the use of Et3N as base, since the use of more nucleophilic DIMPTH(OH)2 alkoxides precluded the formation of the ligands. Representative ligands of each family were evaluated in the asymmetric copper catalyzed addition reaction of Et2Zn to 2-cyclohexenone, 2-cyclopentenone and acyclic alpha-beta-unsaturated ketones. Noteworthy, the less hindered and simple phosphonate ligand derived from DIMPTH(OH)2 induced enantioselection in the more difficult asymmetric reactions.