Selective oxidation of sulfides to sulfoxides and sulfones using 30% aqueous hydrogen peroxide and silica-vanadia catalyst

A green, efficient and selective approach for the oxidation of sulfides to sulfoxides and sulfones with stoichiometric amount of 30% aq. H₂O₂ is reported. The reaction is performed in methanol with silica-vanadia as heterogeneous and reusable catalyst.     

Highly selective 30% hydrogen peroxide oxidation of sulfides to sulfoxides using micromixing

The highly selective oxidation of sulfides to sulfoxides using 30% hydrogen peroxide has been achieved under catalyst-free conditions using a T-shaped micromixer.     

Selective synthesis of sulfoxides and sulfones by tantalum(V) catalyzed oxidation of sulfides with 30% hydrogen peroxide

The reaction of sulfides with 30% hydrogen peroxide catalyzed by tantalum(V) chloride in acetonitrile, i-propanol, or t-butanol selectively provided the corresponding sulfoxides in high yields. On the other hand, the reaction of sulfides with 30% hydrogen peroxide-catalyzed by tantalum(V) chloride or tantalum(V) ethoxide in methanol effectively gave the sulfones.     

Copper catalyzed oxidation of sulfides to sulfoxides with aqueous hydrogen peroxide

Copper(II) complex 1 catalyzes the oxidation of sulfides to sulfoxides with 30% H₂O₂ in high yields. Addition of a catalytic amount of TEMPO to the reaction mixture enhances the conversion and selectivity. Complex 1 can be recycled without loss of activity.     

Gold(III) catalyzed oxidation of sulfides to sulfoxides with hydrogen peroxide

Au(III) catalyzed oxidation of sulfides to sulfoxides with 30% hydrogen peroxide in good yields and chemoselectivities was developed. It was shown that the catalyst loading can be decreased to 0.01 mol % with the good activity and chemoselectivity. Meanwhile, the catalyst was stable in the reaction system, which can be reused at least six cycles with similar activity and chemoselectivity.     

TMSCl-promoted selective oxidation of sulfides to sulfoxides with hydrogen peroxide

Selective oxidation of sulfides to sulfoxides is achieved using H₂O₂ and TMSCl as the promotor. Aromatic and aliphatic sulfides are oxidized to sulfoxides in excellent yields and in short reaction times. Different functional groups including ketone, alkene, ester, and alcohol are tolerated.     

Selective hydrogen peroxide oxidation of sulfides to sulfoxides or sulfones with MWW-type titanosilicate zeolite catalyst under organic solvent-free conditions

Selective oxidation of sulfides to sulfoxides and sulfones with hydrogen peroxide under organic solvent-free conditions was demonstrated by the MWW-type titanosilicate zeolite catalyst. Sulfides were oxidized smoothly to give sulfoxides with good selectivities at ambient temperature using 1.0–1.2 equiv of hydrogen peroxide with the MWW-type titanosilicate zeolite catalyst. Especially, the Ti-MWW with an interlayer-expanded structure (Ti-IEZ-MWW) catalyst showed high activity with good chemoselectivity for the oxidation of various sulfides. The catalyst is recyclable for at least five cycles, and the only byproduct is water. Sulfides were directly oxidized to give sulfones in high yields by 2.5 equiv of hydrogen peroxide with the MWW-type titanosilicate zeolite catalyst under organic solvent-free conditions.     

Selective oxidation of sulfides to sulfoxides using a silica immobilised vanadyl alkyl phosphonate catalyst

A range of sulfides can be selectively oxidised to the corresponding sulfoxides in good yields using catalytic quantities of immobilised vanadyl, cobalt or nickel alkyl phosphonates and the reoxidant sodium bromate or vanadyl alkyl phosphonate with tert-butyl hydroperoxide or aqueous hydrogen peroxide as oxidants.     

Effective oxidation of sulfides to sulfoxides with hydrogen peroxide under transition-metal-free conditions

A "green" highly selective oxidation of organic sulfides to the corresponding sulfoxides was developed using hydrogen peroxide and glacial acetic acid under transition metal-free and mild conditions. The oxidation procedure is very simple and the products are easily isolated in excellent yields (90-99%).     

Tantalum(V) or niobium(V) catalyzed oxidation of sulfides with 30% hydrogen peroxide

Tantalum(V) and niobium(V) are effective catalysts for the oxidation of sulfides with 30% hydrogen peroxide. The reaction of sulfides with 30% hydrogen peroxide catalyzed by tantalum(V) chloride or niobium(V) chloride in acetonitrile, i-propanol or t-butanol selectively provided the corresponding sulfoxides in high yields. The corresponding sulfones are efficiently obtained from the reaction of sulfides with 30% hydrogen peroxide in methanol catalyzed by tantalum(V) or niobium(V).     

Mn(III)-catalyzed oxidation of sulfides to sulfoxides with hydrogen peroxide

Sulfides were selectively oxidized to the corresponding sulfoxides in good yields with hydrogen peroxide using a manganese(III) Schiff-base complex as a catalyst in glacial acetic acid as solvent under mild conditions.     

12-Tungstocobaltate(II) catalyzed selective oxidation of sulfides to sulfoxides using aqueous hydrogen peroxide under solvent free conditions

12-Tungstocobaltate(II) is found to be a selective, recyclable catalyst for the oxidation of sulfides into sulfoxides. The reaction was carried out under solvent free conditions using 30% H₂O₂.     

Selective aerobic oxidation of sulfides to sulfoxides catalyzed by coenzyme NAD models

Coenzyme NAD⁺ models can be applied in the photooxygenation of sulfides to sulfoxides as organocatalysts at room temperature. A series of sulfoxides are synthesized easily with this protocol and the possible mechanism is discussed. This procedure provides a reliable approach to the clean production of useful sulfoxides in synthetic chemistry.     

An efficient solvent free catalytic oxidation of sulfides to sulfoxides with hydrogen peroxide catalyzed by a binaphthyl-bridged Schiff base titanium complex

A titanium binaphthyl-bridged Schiff base complex proved to be an efficient catalyst for the hydrogen peroxide oxidation of aromatic and aliphatic sulfides to the corresponding sulfoxides in satisfactory yields under solvent-free conditions.     

Selective,metal-free oxidation of sulfides to sulfoxides Using 30% hydrogen peroxide catalyzed with <Emphasis Type="Italic">N</Emphasis>-bromosuccinimide (NBS) under neutral buffered reaction conditions

Various types of aromatic and aliphatic sulfides are selectively oxidized to the corresponding sulfoxides in good to excellent yields using 30% H₂O₂ in the presence of catalytic amounts of N-bromosuccinimide (NBS) in buffered aqueous acetonitrile solution (pH =7.00). The results showed that acid sensitive functional groups such as double bonds, and O,O-acetals remained intact under the described reaction conditions     

Copper–Schiff base complex catalyzed oxidation of sulfides with hydrogen peroxide

A straightforward, efficient, and selective oxidation of sulfide to sulfoxide with 30% H₂O₂ catalyzed by copper(II)–Schiff base complex is described. The reactions proceed under mild conditions in acetonitrile at room temperature to provide a variety of aryl and alkyl sulfoxides in excellent yield.     

Selective and mild oxidation of sulfides to sulfoxides by H_2O_2 using DBUH-Br_3 as catalyst

<正>DBUH-Br_3 catalyzed selective conversion of sulfides to sulfoxides in the presence of H_2O_2 as oxidizing agent is described.The reaction was performed selectively at room temperature and relatively short reaction times.     

Selective oxidation of glycosyl sulfides to sulfoxides using magnesium monoperoxyphthalate and microwave irradiation

A protocol that uses moist magnesium monoperoxyphthalate (MMPP) as an oxidant under microwave irradiation rapidly yields a variety of glycosyl sulfoxides from corresponding sulfides in high yields with high selectivity.     

Selective oxidation of allylic sulfides by hydrogen peroxide with the trirutile-type solid oxide catalyst LiNbMoO(6).

Chemoselective sulfur oxidation of allylic sulfides containing double bonds of high electron density due to multiple alkyl substituents or extended conjugation was developed using the composite metal oxide catalyst, LiNbMoO(6), without any epoxidation of the electron-rich double bond(s). Selective oxidation to either the corresponding sulfoxides or the sulfones was realized by controlling the stoichiometry of the quantitative oxidant, H(2)O(2). This new oxidant system had general applicability for chemoselective oxidation of various allylic, benzylic, or propargylic sulfides containing unsaturated carbon-carbon bonds with different electron properties. Various functional groups including hydroxy, formyl, and ethers of THP or TBDMS are compatible under this mild oxidation reaction condition.