Rare-earth metal amido complexes supported by bridged bis(β-diketiminato) ligand as efficient catalysts for hydrophosphonylation of aldehydes and ketones

A series of rare-earth metal amides supported by a cyclohexyl-linked bis(β-diketiminato) ligand were synthesized, and their catalytic activities for hydrophosphonylation of aldehydes and ketones were developed. Reaction of [(Me 3 Si) 2 N] 3 RE(µ-Cl)Li(THF) 3 with the cyclohexyl-linked bis(β-diketimine) H 2 L ( 1 ) (L = Cy[NC(Me)CHC(Me)NAr] 2 , Cy = cyclohexyl, Ar = 2, 6- i -Pr 2 C 6 H 3 ) gave the rare-earth metal amides LREN(SiMe 3 ) 2 (RE = Nd( 2 ), Sm( 3 ), Dy( 4 ), Er( 5 ), Y( 6 )). All complexes were fully characterized by elemental, spectroscopic and single-crystal X-ray analyses. Investigation of the catalytic properties of the complexes reveals that these complexes exhibited a high catalytic activity towards the hydrophosphonylation of aldehydes and ketones in the presence of a very low loading of rare-earth metal amides (0.1–1 mol%) at room temperature in a short time.