Ultrasonic-assisted ruthenium-catalyzed oxidation of some organic compounds in aqueous medium

Ultrasonic generation of ruthenium complexes K2[RuO3(OH)2] and [RuO4] is reported from K2[RuCl5(H2O)] with excess K2S2O8 in 1 M KOH and/or with excess KIO4 in biphasic solvent system (H2O/CH2Cl2/CH3CN) at room temperature. Dehydrogenation of some primary amines to nitriles and primary alcohols to their respective acids by K2[RuCl5(H2O)] with excess K2S2O8 at room temperature was reported. A number of nitriles were hydrated to amides by the same catalyst system at 100 °C. The oxidation of two arenes and four alkenes to their aldehydes, ketones or acids by K2[RuCl5(H2O)] with excess KIO4 using ultrasonic irradiation technique was also reported. Cyclic voltammetric, electronic and Raman spectroscopic techniques have been used to elucidate the nature of the active species present in these catalytic oxidation reactions.