Catalytic oxidation of olefins and alcohols with hydrogen peroxide in a two-phase system giving mono- and dicarboxylic acids

Abstract

The present study considered the influence of various factors on the catalytic activity of systems based on a combination of tetrakis(oxodiperoxotungsto)phosphate(3-) with quater nary ammonium cations, for example, with methyltri n octylammonium [Me(n C 8 H 17 ) 3 N] + . The catalysts were tested in oxidation of cycloolefins (cyclohexene and cyclooctene), alcohols (octan 1 ol and phenylmethanol), and unsaturated fatty acids (cis 9 octadecenoic and 12 hydroxy 9Z octadecenoic acids) with a 30% hydrogen peroxide solution. These reactions proceed under mild conditions (atmospheric pressure, 80-90 °C) to give carboxylic acids. The catalytic systems were characterized by vibrational (IR and Raman) spectroscopy. The state of the systems formed from various precursors, viz., polyoxometallates and phase transfer cata lysts, was studied. It was demonstrated for the first time that the structure formation of peroxo complexes depends on the nature of the halide anion of the quaternary ammonium salt used. The melting points of individual catalytic complexes were determined. The optimal conditions for oxidation were found.

New Insights on the Oxidation of Unsaturated Fatty Acid Methyl Esters Catalyzed by Niobium(V) Oxide. A Study of the Catalyst Surface Reactivity

“…These results lead us to conclude that there is no participation of η 2 -peroxo-type (NbO2) complex in the oxidative process, which would lead to the initial formation of an epoxide and subsequently of diols, ketones or carboxylic acids [47,[85][86][87]. In addition, the high degree of oxidation of Nb2O5 should also preclude Fenton-like processes involving hydroxyl radical formation as a reactive species (if formed, these are efficiently quenched by reaction with hydrogen peroxide-forming water and hydroperoxyl radical-before reaching the lipidic carbon chain).…”

Synthesis of azelaic acid from vegetable oil‐based feedstocks

“…MO was converted selectively with 97% yield to nonanal and methyl 9-oxononanoate as sole products. Na 3 {PO 4 Pai et al demonstrated the significant influence of the halide anion in the quaternary ammonium salt precursor on the catalytic activity [69]. N-hexadecylpyridinium tetra(diperoxotungsto)phosphate was recognized as suitable catalyst for the cleavage of both OA (86% AA) and RA (84% AA) with 30% aq.…”

From crops to products for crops: preserving the ecosystem through the use of bio-based molecules

“…The method developed by Pai (2005) involves the oxidation of oleic acid with the same oxidizing system H 2 O 2 /Q 3 {PO 4 [WO(O 2 ) 2 ] 4 } as in our process, but with a catalyst formed ex situ, with a treatment performed at room temperature and an extraction of fatty acids with dichloromethane.The second process, developed by Abboud (2011), uses a conventional oxidizing agent, potassium permanganate, and sodium oleate (NaOA) as the substrate. At the end of the reaction, sulfuric acid is added to generate the acids, which are extracted at room temperature with ethyl acetate.…”

“…9. Processes developed by Godard et al (2013a), Pai (2005), and Abboud (2011). OA + O 3 /O 2 → AP + AA+ mixture of by-products…”