Deoxygenation Of Sulfoxides Research Articles

ChemInform Abstract: Deoxygenation of Sulfoxides to Sulfides with Thionyl Chloride and Triphenylphosphine: Competition with the Pummerer Reaction.

Although a number of methods have been developed to reduce sulfoxides to sulfides, many of these processes are limited by side reactions, low yields, poorly available reagents, or harsh reaction conditions. We recently studied the reaction of various sulfoxides with SOCl2 and Ph3P. We were able to obtain the corresponding sulfides in excellent yields (>90%) when aliphatic and aromatic sulfoxides were treated with SOCl2 as a catalyst and Ph3P in THF at room temperature.

ChemInform Abstract: Ruthenium Nanocatalysis on Redox Reactions

AbstractReview: 388 refs.

A very useful and mild method for the deoxygenation of sulfoxide to sulfide with silica bromide as heterogeneous promoter

Silica bromide (SB) as heterogeneous reagent and promoter is prepared from reaction of silica gel with PBr3 as a non-hydroscopic, filterable, cheap, and stable yellowish powder that can be stored for months. The results show that the SB is suitable and efficient reagent for deoxygenation of sulfoxides to the corresponding sulfides under mild conditions at room temperature. The easy availability of this reagent makes this simple procedure attractive and a practical alternative to the existing methods.

ChemInform Abstract: An Unprecedented Use for Glycerol: Chemoselective Reducing Agent for Sulfoxides.

AbstractA molybdenum catalyst is found to be highly efficient for the chemoselective deoxygenation of sulfoxides to afford the corresponding sulfides.

Ruthenium Nanocatalysis on Redox Reactions

Nanoparticles have generated intense interest over the past 20 years due to their high potential applications in different areas such as catalysis, sensors, nanoscale electronics, fuel and solar cells and optoelectronics. As the large fractions of metal atoms are exposed to the surface, the use of metal nanoparticles as nanocatalysts allows mild reaction conditions and high catalytic efficiency in a large number of chemical transformations. They have emerged as sustainable heterogeneous catalysts and catalyst supports alternative to conventional materials. This review focuses on the synthesis, characterization and catalytic role of ruthenium nanoparticles (RuNPs) on the redox reactions of heteroatom containing organic compounds with the green reagent H2O2, a field that has attracted immense interest among the chemical, materials and industrial communities. We intend to present a broad overview of Ru nanocatalysts for redox reactions with an emphasis on their performance, stability and reusability. The growth in the chemistry of organic sulfoxides and N-oxides during last decade was due to their importance as synthetic intermediates for the production of a wide range of chemically and biologically active molecules. Thus design of efficient methods for the synthesis of sulfoxides and N-oxides becomes important. This review concentrates on the catalysis of RuNPs on the H2O2 oxidation of organic sulfides to sulfoxides and amines to N-oxides. The deoxygenation reactions of sulfoxides to sulfides and reduction of nitro compounds to amines are fundamental reactions in both chemistry and biology. Here, we also highlight the catalysis of metal nanoparticles on the deoxygenation of sulfoxides and sulfones and reduction of nitro compounds with particular emphasis on the mechanistic aspects.

Deoxygenation of Sulfoxides to Sulfides with Thionyl Chloride and Triphenylphosphine: Competition with the Pummerer Reaction

Although a number of methods have been developed to reduce sulfoxides to sulfides, many of these processes are limited by side reactions, low yields, poorly available reagents, or harsh reaction conditions. We recently studied the reaction of various sulfoxides with SOCl2 and Ph3P. We were able to obtain the corresponding sulfides in excellent yields (>90%) when aliphatic and aromatic sulfoxides were treated with SOCl2 as a catalyst and Ph3P in THF at room temperature.

Selective and Efficient Deoxygenation of Sulfoxides with NbCl5/Indium System

It has been found that dialkyl, diaryl, and aryl alkyl sulfoxides can be selectively converted to the corresponding sulfides with a NbCl5/In system in good to excellent yields under mild conditions. Several functional groups (bromo, chloro, methoxy, aldehyde, and vinyl) were tolerated under the reaction conditions. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.

ChemInform Abstract: Highly Efficient Rhenium‐Catalyzed Deoxygenation of Sulfoxides Without Adding Any Reducing Agent.

AbstractThe novel method is highly efficient for aromatic and aliphatic sulfoxide substrates.

A polymer analogous reaction for the formation of imidazolium and NHC based porous polymer networks

A polymer analogous reaction was carried out to generate a porous polymeric network with N-heterocyclic carbenes (NHC) in the polymer backbone. Using a stepwise approach, first a polyimine network is formed by polymerization of the tetrafunctional amine tetrakis(4-aminophenyl)methane. This polyimine network is converted in the second step into polyimidazolium chloride and finally to a polyNHC network. Furthermore a porous Cu(II)-coordinated polyNHC network can be generated. Supercritical drying generates polymer networks with high permanent surface areas and porosities which can be applied for different catalytic reactions. The catalytic properties were demonstrated for example in the activation of CO2 or in the deoxygenation of sulfoxides to the corresponding sulfides.

An unprecedented use for glycerol: chemoselective reducing agent for sulfoxides

A new application for glycerol that expands its possibilities beyond a green solvent and a precursor of value-added products has been demonstrated. Simple, easily available, and environmentally friendly dioxomolybdenum(VI) complexes are highly efficient catalysts for the chemoselective sulfoxide deoxygenation with this biomass-derived chemical feedstock. Both refined glycerol and crude glycerin can be used, thus expanding the potential application of this reaction. Subsequent transformation of glycerol during this reductive process has also been investigated.

NaI/silica sulfuric acid as an efficient reducing system for deoxygenation of sulfoxides in poly ethylene glycol (PEG-200)

Deoxygenation of structurally diverse sulfoxides including dialkyl, diaryl, aryl alkyl and allyl sulfoxides to the corresponding sulfides were carried out using a NaI/silica sulfuric acid reducing system at room temperature in poly ethylene glycol (PEG-200) in excellent yields.

Zinc-Catalyzed Deoxygenation of Sulfoxides to Sulfides Applying [B(Pin)]2 as Deoxygenation Reagents

In the present study, the zinc-catalyzed deoxygenation of aliphatic and aromatic sulfoxides in the presence of 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi-1,3,2-dioxaborolane [B(Pin)]2 as reducing reagent to produce the corresponding sulfides has been investigated. After examination of various reaction parameters the abilities of catalytic amounts of Zn(OTf)2 has been proven in the deoxygenation of various sulfoxides. Especially, a high functional group tolerance was noticed for the Zn(OTf)2/B(Pin)2 system.

I2 as a mild and efficient catalyst in deoxygenation of sulfoxides with thioacetic acid

An effective procedure for deoxygenation of sulfoxides to sulfides using thioacetic acid as a reducing agent and a catalytic amount of I2 in MeCN at ambient temperature has been developed. Using this protocol, a variety of sulfoxides including benzyl, allyl, alkyl and aryl sulfoxides have been successfully reduced to the corresponding sulfides in excellent yields.

Highly efficient rhenium-catalyzed deoxygenation of sulfoxides without adding any reducing agent

This work reports a novel method for the deoxygenation of aromatic and aliphatic sulfoxides catalyzed by oxo-rhenium complexes without adding any reducing agent. The oxo-rhenium complex ReOCl3(PPh3)2 proved to be very efficient for the deoxygenation of several sulfoxides with tolerance of different functional groups.

Deoxygenation of Sulfoxides to Sulfides in the Presence of Zinc Catalysts and Boranes as Reducing Reagents

In the present study, the zinc-catalyzed deoxygenation of aliphatic and aromatic sulfoxides in the presence of boranes as reducing reagent has been explored. After investigation of different reaction parameters the abilities of catalytic amounts of Zn(OTf)2 has been demonstrated in the deoxygenation of various sulfoxides. Moreover, various experiments have been performed to shed light on the underlying reaction mechanism.

Molybdenum oxo–peroxo complex: A very fast catalyst for oxidation and reduction of sulfur-based compounds

Abstract We have evaluated the catalytic activity of a molybdenum(VI) oxo–peroxo complex through the oxidation and reduction of sulfur-based compounds. Arylalkyl, diaryl and dialkyl sulfides are selectively oxidized to corresponding sulfoxides, with tert -butyl hydroperoxide (TBHP), in the presence of MoO(O 2 )(phox) 2 complex as catalyst. This molybdenum complex was also found to be an efficient catalyst for the deoxygenation of sulfoxides to sulfides with PPh 3 in excellent yields and chemoselectivity.

ChemInform Abstract: Cyanuric Chloride as Promoter for the Oxidation of Sulfides and Deoxygenation of Sulfoxides.

AbstractThe title reagent can be applied to both processes under either conditions A) or B).

Efficient recyclable catalytic system for deoxygenation of sulfoxides: catalysis of ionic liquid-molybdenum complexes in ionic liquid solution

Three newly synthesized room temperature ionic liquids containing molybdate anion, [DMIm][MoO2(NCS)4], [RPy][MoO2(NCS)4] (R = butyl or decyl), and previously reported [BMIm][MoO2(NCS)4] were used as catalysts for the reduction of sulfoxides. For facilitating the recyclability of the catalysts, the ionic liquids [RMIm][PF6] and [RPy][PF6] (RMIm = 1-n-alkyl-3-methylimidazolium, RPy = 1-n-alkylpyridinium) were applied as ionic solvents and toluene is used as solvent for the organic phase. Molybdenum salts immobilized in RTILs constituted a reusable and efficient heterogeneous catalyst system. A maximum conversion (>99%) was achieved for reduction of diphenyl sulfoxide to diphenyl sulfide as a model substrate by using triphenylphosphine as reducing agent at 50 °C after 20 h. This system gave the best results in terms of catalyst/solvent recycling and no loss of catalytic activity was observed after 8 cycles.

ChemInform Abstract: Low‐Valent Molybdenum‐Based Dual Pre‐Catalysts for Highly Efficient Catalytic Epoxidation of Alkenes and Deoxygenation of Sulfoxides.

AbstractThe Mo complexes exhibit high activity in both types of reactions.

Cyanuric chloride as promoter for the oxidation of sulfides and deoxygenation of sulfoxides

This Letter discusses the use of cyanuric chloride as an efficient promoter for the chemoselective oxidation of sulfides to the corresponding sulfones in the presence of H2O2 as the terminal oxidant. Sulfoxides were also found to undergo deoxygenation to sulfides with cyanuric chloride and potassium iodide system. The reaction is broad in scope and easy to perform.