Tungstoborates as Highly Active Catalysts for Cycloalkane Oxygenation Using Hydrogen Peroxide

Abstract

Keggin-type tungstoborates [BW 12 O 40 ] 5-, H x [BW 11 O 39 ] 9-x)-and [BM(H 2 O)W 11 O 39 ] 6-, M = Fe III , Mn III or Ru III proved to be highly active catalysts for the H 2 O 2 oxidation of cyclooctane and cyclohexane to the corresponding ketone, alcohol and alkyl hydroperoxide derivatives. High turnover numbers and high selectivity for the hydroperoxide were observed.

Manganese Mono-Substituted Borotungstate: Characterization and Catalytic Application

“…3). Table 1 presents the data for the first coordination sphere of Mn in BW 11 Mn framework what is formed by six oxygen atoms in the range Catalytic activity. The oxidation of cis-cyclooctene (1a) (Scheme 1) was carried out at 80ºC in homogeneous phase using H 2 O 2 (30% wt) as oxidant in acetonitrile (1.5mL) in the presence of catalytic amounts of BW 11 Mn.…”

“…The Keggin anions and their derivatives have been used as catalysts for various types of oxidative reactions, like the epoxidation of alkenes and the hydroxylation of alkanes [3][4][5]. In particular, transition metal mono-substituted Keggin-type heteropolytungstates, [XW 11 M(H 2 O)O 39 ] (n-m)-(X = P, Si, B), in which a transition metal cation, M n+ , is co-ordinated to the binding sites of lacunary heteropolyanion α-[XW 11 O 39 ] n-, have generated great interest as oxidative catalysts [6][7][8][9][10][11][12][13]. Even so, oxidative catalysis in the presence of Keggin-type mono-substituted borotungstates has not been widely studied and only a few reports were found.…”

“…Even so, oxidative catalysis in the presence of Keggin-type mono-substituted borotungstates has not been widely studied and only a few reports were found. [11][12]. In this work, we present some structural studies on the tetra-butylammonium salt of the borotungstate anion [BW 11 Mn(H 2 O)O 39 ] 6-, and its use in the oxidation of cis-cyclooctene, as a model substrate.…”