Selective and efficient oxidation of sulfides to sulfoxides with N-bromosuccinimide in the presence of β-cyclodextrin in water

A simple and highly selective oxidation of sulfides to sulfoxides with N-bromosuccinimide (NBS) catalyzed by β-cyclodextrin in water has been developed. A series of sulfides were oxidized selectively at room temperature in excellent yields. This reaction proceeds without over-oxidation to sulfones under mild conditions using water as a solvent and has many advantages over the existing methodologies.     

Method for synthesis of alkyl vinyl sulfides by the direct vinylation of thiols in aprotic dipolar solvents

Conclusions A method was developed for the synthesis of vinyl alkyl sulfides by the nucleophilic addition of thiols to acetylene in aprotic dipolar solvents, like hexamethylphosphoric triamide and dimethyl sulfoxide.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 956–957, April, 1972.     

2,6-Dicarboxypyridinium chlorochromate: an efficient and selective reagent for the oxidation of thiols to disulfides and sulfides to sulfoxides

2,6-Dicarboxypyridinium chlorochromate (2,6-DCPCC) was found to be an efficient reagent for the conversion of thiols to disulfides and sulfides to sulfoxides under neutral and anhydrous conditions in good to excellent yields. Selective oxidation of thiols in the presence of sulfides at room temperature is also observed with this reagent.     

Fast and highly efficient solid state oxidation of thiols

A fast and efficient solid state method for the chemoselective room temperature oxidative coupling of thiols to afford their corresponding disulfides using inexpensive and readily available moist sodium periodate as the reagent is described. The reaction was applicable to a variety of thiols giving high yields after short reaction times. Comparison of yield/time ratios of this method with some of those reported in the literature shows the superiority of this reagent over others under these conditions.     

Graphite oxide: a selective and highly efficient oxidant of thiols and sulfides

The selective oxidation of thiols to disulfides and sulfides to sulfoxides using graphite oxide (GO), a heterogeneous carbocatalyst obtained from low cost, commercial starting materials is described. The aforementioned oxidation reactions were found to proceed rapidly (as short as 10 min in some cases) and in good yield (51-100%) (19 examples). No over-oxidation of the substrates was observed, and GO's heterogeneous nature facilitated isolation and purification of the target products.     

An efficient asymmetric oxidation of sulfides to sulfoxides

The Sharpless reagent (Ti(OiPr)₄ + 1 mol eq. diethyl tartrate (DET) + 2 t-BuOOH) modified by addition of one mol eq. H₂O gives a new homogeneous reagent which cleanly oxidizes sulfides into sulfoxides in dichloromethane. The best results were obtained for the stoichiometry Ti/DET/H₂O/t-BuOOH = 1:2:1:2. The e.e. observed ranged from 4 to 93% with the highest beeing observed in the case of methyl p-toly] sulfoxide.     

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.     

溴酸苄基三苯基膦的氧化性能研究

利用溴酸钠与氯化苄基三苯基膦作用得到溴酸苄基三苯基膦氧化剂。该氧化剂热稳定性好,氧化性能温和,在非质子有机溶剂中和在Lewis酸存在下,有效地将苄醇、环醇、和α-羟基酮氧化为相应的羰基化合物,产率较高;将苯硫酚氧化为二硫化物,产率中等。此外,对该氧化剂氧化烷基苯为醛、酮及羧酸,氧化芳醛为羧酸也作了研究。     

A mild and efficient protocol for oxidation of thiols to disulfides in water

A novel vanadium polyoxometalate [(C₇H₇)(CH₃)₃N]₃[H₃V₁₀O₂₈].3H₂O works as a useful oxidant for the oxidation of thiols to disulfldes in water under mild reaction conditions in an excellent yield. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 23:231–234, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20760     

TEMPO-linked metalloporphyrins as efficient catalysts for selective oxidation of alcohols and sulfides

Six new TEMPO-linked porphyrins and metalloporphyrins were synthesized and they exhibited efficient catalytic activity for selective oxidation of alcohols and sulfides to the corresponding aldehydes, ketones and sulfoxides using NaOCl as oxidant.     

Fe(NO3)3·9H2O/Fe(HSO4)3: An efficient reagent system for the oxidation of alcohols, thiols and sulfides in the absence of solvent

Fe(NO3)3·9H3O/Fe(HSO4)3 was used as an efficient reagent system for the oxidation of alcohols to their corresponding carbonylcompounds. All reactions were performed in the absence of solvent in good to high yields. Under the same reaction conditions,thiols and sulfides were also converted to their corresponding disulfides and sulfoxides, respectively.     

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.     

Fe3O4@S‐ABENZ@VO: Magnetically separable nanocatalyst for the efficient,selective and mild oxidation of sulfides and oxidative coupling of thiols

Oxovanadium(IV) immobilized on Fe₃O₄@S‐ABEN is reported as a highly efficient nanocatalyst for the oxidation of sulfides and oxidative coupling of thiols (using H₂O₂ as green oxidant), the products of which are obtained in high to excellent yields. The products can be separated by a simple extraction with organic solvent and the catalyst is highly efficient, especially in terms of selectivity of desired product. The catalytic system can be recycled and reused without significant loss of catalytic activity.     

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.     

Electroosmotic transport of water and aprotic solvent in heterogeneous membranes

Electrosmotic water transport in MK-40, MA-40, and MA-41 electrodialysis membranes before and after their treatment by aprotic solvent solution and electroosmotic permeability of a MK-40/MA-40 membrane couple in water and N,N-dimethyl acetamide were studied for the first time. It is found that N,N-dimethyl acetamide produces practically no effect on the properties of the studied ion-exchange materials and its transport number through the MK-40/MA-40 membrane couple is independent both of the initial lithium chloride concentration in a desalting cell of the concentrator electrodyalizer and its volume fraction in the solution. The initial concentration of lithium chloride in the desalting cell does not affect the transport numbers of water in the studied membrane couple either. However, these depend on the volume fraction of the organic component in the solution and this dependence features an extremum. A method for estimation of electroosmotic permeability of the membrane couple in aqueous-organic solutions of electrolytes is suggested.     

Selective hydrogenation of nitrobenzene in aprotic media

The kinetics of hydrogenation of nitrobenzene in aprotic media was studied, and a scheme of the mechanism and a kinetic equation, corresponding to it, for the initial reaction rate are proposed. High selectivity with respect to N-phenylhydroxylamine is apparently due to the aprotic nature and donor properties of the solvent and also to the functioning of the catalyst as a unique hydrogen electrode.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 45–48, January, 1991.The author thanks V. V. Strelets for useful discussion.     

Preparation of DSA@MNPs and application as heterogeneous and recyclable nanocatalyst for oxidation of sulfides and oxidative coupling of thiols

Research on Chemical Intermediates - Dopamine sulfamic acid-functionalized magnetic Fe3O4 nanoparticles (DSA@MNPs) were prepared by a very simple and inexpensive procedure using commercial...