Homocoupling of Aryl Grignard Reagents Catalyzed by Iron Complexes Bearing β-Aminoketonato Ligand

摘要

Metal complexes bearing β-diketonato ligands can be commercially available and extensively used instead of halogeno-salts. β-Diketonato ligand acts as three-electron donor bidentate ligand and thus these complexes are more stable toward oxygen and moisture than halogeno-salts. On the other hand, β-diketiminato ligands, which have bulky organic nitrogen groups instead of both oxygen atoms on β-diketonatos, recently attracted much attention for the synthesis of coordinatively unsatureated species. This feature was considered that the bulky β-diketiminato ligands might prevent the reactivity of the metal with various organic molecules. Therefore, we have been interested in the utilization of β-aminoketonato ligands, which are conceived to control the stability and/or reactivity of the metal (Figure 1). Furthermore, these ligands are easily prepared from β-diketone with various primary amines and thus modifications of steric and electronic factors might be achieved. We have started our study on β-aminoketonato complexes of iron, cobalt, and so on, concerning the synthesis, structure, and reactivity of these complexes.