Studies on polyoxo and polyperoxo-metalates part 511Part 4: Ref. [4].: Peroxide-catalysed oxidations with heteropolyperoxo-tungstates and -molybdates

Gresley, N. Melanie; Griffith, William P.; Laemmel, Anne C.; Nogueira, Helena I. S.; Parkin, Bernardeta C.

doi:10.1016/s1381-1169(96)00256-7

Cited by 129 publications

(50 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hence the splitting of these modes indicated in Table 2 the Raman at 861 cm 1 [most Á 2 -peroxo complexes have strong Raman bands near 870 cm 1 (Ref. 28)], but appears only as a very weak band in the IR spectrum since there will be no dipole change for such a vibration. In a brief report 27 of its Raman spectrum this band was given as 870 cm 1 , but we have studied several natural and synthetic samples and this mode is always at 861 cm 1 .…”

Section: Studtite Uo 2 (O 2 )·4h 2 Omentioning

confidence: 99%

Raspite and studtite: Raman spectra of two unique minerals

Bastians

Crump

Griffith

et al. 2004

J Raman Spectroscopy

Self Cite

View full text Add to dashboard Cite

The Raman and IR spectra of monoclinic naturally occurring raspite, a-PbWO 4 (space group P2 1 /a) were measured; it is irreversibly transformed to the tetragonal stolzite, b-PbWO 4 , by heating to 450 • C, and this process was followed by Raman spectroscopy. Assignments of fundamental modes are proposed. New data are also presented on single crystals of stolzite (space group I4 1 /a), and it is shown that raspite and stolzite can easily be distinguished by their Raman spectra. We also present Raman and IR spectroscopic data on natural and synthetic studtite, UO 4 ·4H 2 O, and its synthetic dehydration product metastudtite, UO 4 ·2H 2 O, the only two naturally occurring peroxide-containing minerals, and on partially deuterated synthetic forms of these materials. Assignments of fundamental modes are proposed and both TGA and DSC data are presented for studtite.

show abstract

Section: Studtite Uo 2 (O 2 )·4h 2 Omentioning

confidence: 99%

Raspite and studtite: Raman spectra of two unique minerals

Bastians

Crump

Griffith

et al. 2004

J Raman Spectroscopy

Self Cite

View full text Add to dashboard Cite

show abstract

“…[38][39][40] While a mass of oxygen donors are available, utilization of H2O2 as "green" oxygen donor has become increasingly prominent. [41][42][43][44] In this work, catalytic oxidation of thioanisole in the presence of P2W15@Al2O3 as catalyst and H2O2 as oxidant has been carried out (Scheme 2). The selectivity of sulfoxide products and the conversion of the initial sulfides have been quantified using gas Figure S10-S12, and Table S3).…”

Section: Resultsmentioning

confidence: 99%

Covalent Immobilization of Polyoxotungstate on Alumina and Its Catalytic Generation of Sulfoxides

Hong

Win

Zhang

et al. 2016

Chemistry A European J

View full text Add to dashboard Cite

Structural and chemical stability of the immobilized polyoxometalates (POMs)-containing catalysts is one crucial factor for their industrial application. In this work, we discuss the preparation of a novel P2W15@Al2O3 catalyst using a facile condensation reaction between the tri-lacunary POM of Na12[α-P2W15O56]·24H2O (P2W15) and the hydroxyl groups on the surface of the spherical γ-Al2O3 under acidic conditions. The heterogeneous catalyst was characterized by the 31 P NMR, FT-IR, XRD, XPS, TG, Raman, HR-TEM and BET. The P2W15@Al2O3 catalyst showed excellent stability, highly efficient reactivity and selectivity for the oxygenation of thioethers to sulfoxides which are a very useful intermediate in organic synthesis and industrial preparation of drugs. The catalyst could be recycled and reused at least ten times without any observable loss of its catalytic efficiency, mainly due to the covalently grafted {P2W15} cluster and high dispersion onto the γ-Al2O3 surface.Polyoxometalates (POMs) are a class of discrete anionic metal-oxides of V, Mo, W and Nb etc.

show abstract

“…The reaction was not completed within 24 h (Table 1, entry 6). Consequently, it was performed in different molar ratios of the catalyst in the presence of oxidant in order to obtain the optimum reaction conditions (Table 1, entries [1][2][3][4][5].…”

Section: Resultsmentioning

confidence: 99%

“…Syntheses of sulfoxides are usually achieved by oxidation of their corresponding sulfides. During the last years, various procedures for H 2 O 2 oxidation of sulfides including the use of various heterogeneous catalyst systems have been reported [4][5][6]. The application of this oxidant has been developed due to its effective oxygen content, eco-friendly nature, low cost, and also safety in storage and operation [7,8].…”

mentioning

confidence: 99%