Highly effective aldose reductase mimetics: Microwave-assisted catalytic transfer hydrogenation of d-glucose to D-sorbitol with magnetically recoverable aminomethylphosphine-Ru(II) and Ni(II) complexes

Abstract The novel Ru(II) and Ni(II) complexes of aminomethylphosphine ligands supported on Fe3O4@SiO2 (core@shell) surface have been synthesized with Schlenk technique and characterized with Scanning Electron Microscopy (SEM), Energy-Dispersive X-Ray Spectroscopy (EDX), Transmission Electron Microscopy (TEM), X-Ray Diffraction Spectroscopy (XRD), Fourier-Transform Infrared Spectroscopy (FT-IR), Ultraviolet-Visible Spectroscopy (UV-Vis.), Thermogravimetric Analysis/Differential Thermal Analysis/ Differential Thermogravimetry (TG/DTA/DTG) and elemental analysis techniques. Besides, the synthesized complexes were tried as a catalyst in the transfer hydrogenation of D-glucose to D-sorbitol in isopropyl alcohol under microwave power at 150 °C for 1h reaction time. K2CO3 was used as a base source in the catalysis. High-Performance Liquid Chromatography (HPLC) fitted Refractive Index Detector (RID) was used for the quantitative analyses of the catalytic tests. The complexes can be repeatedly usable and magnetically recoverable in the catalytic transfer hydrogenation of D-glucose to D-sorbitol. The complexes are also chemically selective and stable in the catalysis medium. In the recycling experiments, Ru(II) complexes were filtered and washed with isopropyl alcohol (IPA), dried and used again for the other catalytic cycles. Especially Ru(II) complexes showed the best catalytic properties, with over 91% selectivity on over 98 % conversions under microwave power.