Heterogeneously Catalyzed Aerobic Oxidation of Sulfides with a BaRuO₃ Nanoperovskite

Abstract

A rhombohedral BaRuO nanoperovskite, which was synthesized by the sol-gel method using malic acid, could act as an efficient heterogeneous catalyst for the selective oxidation of various aromatic and aliphatic sulfides with molecular oxygen as the sole oxidant. BaRuO showed much higher catalytic activities than other catalysts, including ruthenium-based perovskite oxides, under mild reaction conditions. The catalyst could be recovered by simple filtration and reused several times without obvious loss of its high catalytic performance. The catalyst effect, O-labeling experiments, and kinetic and mechanistic studies showed that substrate oxidation proceeds with oxygen species caused by the solid. The crystal structure of ruthenium-based oxides is crucial to control the nature of the oxygen atoms and significantly affects their oxygen transfer reactivity. Density functional theory calculations revealed that the face-sharing octahedra in BaRuO likely are possible active sites in the present oxidation in sharp contrast to the corner-sharing octahedra in SrRuO, CaRuO, and RuO. The superior oxygen transfer ability of BaRuO is also applicable to the quantitative conversion of dibenzothiophene into the corresponding sulfone and gram-scale oxidation of 4-methoxy thioanisole, in which 1.20 g (71% yield) of the analytically pure sulfoxide could be isolated.

New Type of Catalyst for Efficient Aerobic Oxidative Desulfurization Based On Tungsten Carbide Synthesized by the Microwave Method

“…27 , 28 However, such catalysts as polyoxometalates require laborious synthesis procedures. Catalysts containing noble metals are highly active; 29 − 32 however, the high cost of such catalysts complicates their practical application.…”

Aerobic oxidative CC bond cleavage of aromatic alkenes by a high valency iron-containing perovskite catalyst

“…During the course of our investigation on crystalline first-row metal oxide catalysts, [12][13][14][15][16][17] we have successfully synthesized various hexagonal perovskite nanoparticle catalysts for the liquid phase selective oxidation of various organic substrates with O 2 as the sole oxidant. [15][16][17] In particular, high valency iron-containing BaFeO 3−δ was found to act as an efficient heterogeneous catalyst for the aerobic oxidation of alkanes to the corresponding alcohols and ketones, in sharp contrast to Fe 3+ /Fe 2+ oxides. 17 Herein, we apply the superior oxidizing ability of a BaFeO 3−δ perovskite catalyst to aerobic oxidative CC bond cleavage.…”

Flow Electrosynthesis of Sulfoxides, Sulfones, and Sulfoximines without Supporting Electrolytes

“…The spectroscopic data agree with the literature. 66 N-(Methyl(oxo)(phenyl)-λ6-sulfaneylidene)cyanamide (5a). Compound 5a was synthesized following GP3 using (methylsulfinyl)benzene (2a, 70 mg, 0.5 mmol) to give the product as a yellow oil.…”