NaPMoVO-catalyzed one-pot oxidative esterification of benzaldehyde with hydrogen peroxide.

The activity of the sodium salts of vanadium-doped phosphomolybdic acid was assessed in the oxidative esterification reaction of benzaldehyde with hydrogen peroxide in alkyl alcohol solutions. The effect of main reaction parameters, such as temperature, catalyst load, vanadium doping level, and reactant stoichiometry, on the conversion and reaction selectivity was investigated. Among the tested heteropoly salts, NaPMoVO was the most active and selective catalyst, achieving almost complete conversion of benzaldehyde and high ester selectivity regardless of the alcohol investigated.

Vanadium-doped phosphomolybdic acids as catalysts for geraniol oxidation with hydrogen peroxide.

In this work, vanadium-doped phosphomolybdic acids were evaluated as catalysts in green oxidation routes of terpene alcohols with hydrogen peroxide. A series of phosphomolybdic acids containing a variable load of vanadium cations (, V ions) were synthesized, and tested as catalysts in geraniol oxidation, the model molecule selected. All the catalysts were characterized by powder X-ray diffraction, attenuated diffuse reflectance infrared spectroscopy, UV-Vis spectroscopy, thermogravimetric analysis, N adsorption-desorption isotherms, scanning electronic microscopy, X-ray dispersive spectroscopy, and -butylamine potentiometric titration.

Vanadium-doped sodium phosphomolybdate salts as catalysts in the terpene alcohols oxidation with hydrogen peroxide.

In this work, we have explored the catalytic activity of Keggin-type heteropolyanions PMo V O ( = 0, 1, 2, or 3) in the form of sodium salts in green oxidation routes of terpene alcohols with hydrogen peroxide. Nerol was the model molecule selected to assess the impacts of the main reaction parameters, such as temperature, catalyst load, and stoichiometry of reactants. The impacts of the presence of vanadium at different proportions (, V, V, and V loads/per anion) in the structure of phosphomolybdate catalysts were assessed.

Novel Hg (II) selective fluorescent green sensor based on carbon dots synthesized from starch and functionalized with methimazole.

We describe a green new method for the synthesis of water-soluble photoluminescent carbon dots (CDs) that were functionalized with methimazole (MTZ) and applied to determine Hg based on the fluorescence extinction. Starch obtained from rice was used as a natural source for the production of CDs by hydrothermal treatment. Also, it was proposed a factorial design to optimize the parameters for CD synthesis and the results showed that the luminescence intensity is a function of temperature and not of the heating time in the hydrothermal process.