16823-61-3Relevant articles and documents
A sustainable approach towards solventless organic oxidations catalyzed by polymer immobilized Nb(V)-peroxido compounds with H2O2 as oxidant
Ahmed, Kabirun,Gogoi, Sandhya Rani,Islam, Nashreen S.,Saikia, Gangutri,Sultana, Sazida Yasmin,Talukdar, Hiya
, (2021/11/16)
New heterogeneous catalysts comprising of peroxidoniobium(V) complexes immobilized on amino acid grafted cross-linked poly(styrene-divinylbenzene) resin has been developed. Results of FTIR, Raman, NMR, XPS, XRD, EDX, SEM, BET, TGA, and elemental analysis confirmed the successful anchoring of triperoxidoniobium(V), [Nb(O2)3]? species to the host polymer via the pendant amino acid groups. The supported catalysts exhibited excellent performance in epoxidation of styrene and a range of cyclic and terpenic compounds under environmentally acceptable solvent-free condition, with aqueous H2O2 as oxidant. The catalytic protocols provided excellent conversion to the desired epoxide (up to 100%) with selectivity > 99%, TON as high as 1000, and high H2O2 utilization efficiency (92–97%). Moreover, the catalysts efficiently facilitated chemoselective solvent-free oxidation of a variety of thioethers to sulfones at room temperature. Simple operational strategy, easy recyclability for multiple reaction cycles with the consistent activity-selectivity profile are the additional significant attributes of the developed catalytic processes.
An Efficient Oxidation of Sulfides to Sulfones with Urea-Hydrogen Peroxide in the Presence of Phthalic Anhydride in Ethyl Acetate
Lutz, Marlon,Wenzler, Marta,Likhotvorik, Igor
supporting information, p. 2231 - 2234 (2018/04/16)
A metal-free, environmentally benign oxidation of substituted sulfides directly to their corresponding sulfones is described. Using urea-hydrogen peroxide and phthalic anhydride in ethyl acetate clean conversion into the sulfone was achieved without observation of the possible sulfoxide oxidation product.
Merrifield resin supported peroxomolybdenum(vi) compounds: Recoverable heterogeneous catalysts for the efficient, selective and mild oxidation of organic sulfides with H2O2
Boruah, Jeena Jyoti,Das, Siva Prasad,Ankireddy, Seshadri Reddy,Gogoi, Sandhya Rani,Islam, Nashreen S.
, p. 2944 - 2959 (2013/10/08)
We have generated new heterogeneous catalysts by immobilizing dioxomonoperoxomolybdenum(vi) on amino acid functionalized Merrifield resin, which exhibit excellent activity, stability and selectivity for the oxidation of thioethers and dibenzothiophene (DBT) to the corresponding sulfoxides or sulfones by H2O2 at ambient temperature. The synthetic protocols are high-yielding, halogen-free, environmentally clean and safe, and operationally simple. The catalysts, [MoO2(O2)(L) 2]2--MR [L = valine (MRVMo) or alanine (MRAMo) and MR = Merrifield resin] were prepared by reacting H2MoO4 with 30% H2O2 and the respective amino acid functionalized resin, at near neutral pH. The compounds were characterized by elemental analysis, spectral studies (FTIR, Raman, 13C NMR and 95Mo NMR, diffuse reflectance UV-Vis and XPS), SEM, EDX, XRD, Brunauer-Emmett-Teller (BET) and TGA-DTG analysis. The easy recyclability of the catalysts for several catalytic cycles without change in activity and selectivity, their complete chemoselectivity towards the sulfur group of substrates bearing other oxidation prone functional groups, are important "green" attributes of these catalysts.
