A green, reusable and highly efficient solid acid catalyst for the oxidation of aldehydes to the corresponding carboxylic acids using H2O2 and KMnO4: H5PV2Mo10O40 (10-molybdo-2-vanadophosphoric heteropolyacid)

H5PV2Mo10O40-catalyzed oxidation of aromatic aldehydes to the corresponding carboxylic acids using hydrogen peroxide and KMnO4 as oxidants under mild conditions is reported. This system provides an efficient, convenient and practical method for the oxidation of aromatic aldehydes. In this work, differences between Keggin and Dawson type polyoxometalates are addressed in term of relative stability, hardness and acidity

Introduction of PEG-SANM nanocomposite as a new and highly efficient reagent for the promotion of the silylation of alcohols and phenols and deprotection of the silyl ethers

<p>Poly (ethylene glycol)-sulfonated sodium montmorillonite (PEG-SANM) nanocomposite was prepared by a simple method and characterized using XRD, TGA, SEM, TEM, and FT-IR techniques. After preparation and characterization, this reagent was used as a highly efficient and reusable solid acid catalyst for the chemoselective silylation of alcohols and phenols and deprotection of the obtained silyl ethers. The method offers several advantages including high to excellent yields of the products, short reaction times, easy preparation of the catalyst and easy work-up procedure. In addition, the catalyst can be recycled and reused at least for five times without significant decrease in the catalytic activity.</p