Niobium(V) Chloride Catalyzed Oxidation of Dithioacetals with 30% Hydrogen Peroxide: A Concise Preparation of Bissulfonylmethylene Compounds

Abstract

The oxidation of dithioacetals with 16 eq of 30% hydrogen peroxide in the presence of 10 mol% niobium(V) chloride at room temperature provides bissulfonylmethylenes in high yields.

Low temperature liquid phase catalytic oxidation of aniline promoted by niobium pentoxide micro and nanoparticles

“…There is precedence for the application of niobium catalysts in oxidative processes that employ hydrogen peroxide as oxidant. Most examples involve the epoxidation of alkenes [17], but oxidation of dithioacetals, benzylalcohols, naphthols and sulfides [17][18][19][20][21] have also been reported. Reddy and Sayari demonstrated that vanadium was capable of catalyzing the oxidation of amines in the presence of hydrogen peroxide to afford the corresponding imines and oximes under mild conditions [22].…”

Generating active and non-selective oxidizing species by previous treatment of niobium-doped mesoporous silica with hydrogen peroxide

“…The previous treatment with hydrogen peroxide should generate peroxo groups on the catalyst surface, which makes the catalyst more active. [18][19][20][21] It is interesting to observe that the catalyst without previous treatment with hydrogen peroxide (Nb-MCM) showed an increase in the removal of rhodamine B after 30 min, indicating that after that time the H 2 O 2 added to the reaction system reacted with the surface Nb forming the peroxo group in situ. This result shows clearly that the previous treatment of the catalyst with H 2 O 2 increases the catalytic activity of the silica modified with niobium for oxidation of the organic compound.…”