Hydrogenation of Acetophenone and Its Derivatives with 2-Propanol Using Aminomethylphosphine-Ruthenium Catalysis

Abstract

The reaction of 3′-aminopropyltriethoxysilane with the phosphonium salt ([Ph2P(CH2OH)2]Cl) gives an aminomethylphosphine-type ligand ((CH3CH2O)3Si(CH2)3N(CH2PPh2)2). Reaction of the ligand ((CH3CH2O)3Si(CH2)3N(CH2PPh2)2) with silica gives silica supported aminomethylphosphine ligand (SiO2)-O-Si(CH2)3N(CH2PPh2)2). The ligands were refluxed with [RuCl2(p-cymene)]2 in toluene to give [RuCl2((CH3CH2O)3Si(CH2)3N(CH2PPh2)2)] and silica-supported SiO2)-O-[RuCl2((Si(CH2)3N(CH2PPh2)2)2] complex, respectively. The catalytic studies show that the complexes [RuCl2((CH3CH2O)3Si(CH2)3N(CH2PPh2)2)] and SiO2)-O-[RuCl2((CH3CH2O)3Si(CH2)3N(CH2PPh2)2)2] are very active catalysts for the transfer hydrogenation of acetophenone by 2-propanol in basic media. The best yield was observed in hydrogenation of m-methoxy acetophenone (95%) with catalyst [RuCl2((CH3CH2O)3Si(CH2)3N(CH2PPh2)2)].