Selective alkene epoxidation by molecular oxygen in the presence of aldehyde and different type catalysts containing cobalt

https://doi.org/10.1016/S0167-2991(97)81058-0Get rights and content

Publisher Summary

This chapter discusses a comparative study of the catalytic properties of different type cobalt-containing compounds in alkene epoxidation by dioxygen in the presence of iso-butyraldehyde (IBA) and provides some data that allows clarifying the reaction mechanism and the nature of the catalytic action of cobalt compounds. Here, the catalytic properties of cobalt-containing compounds having different nature have been discussed. These include the simple salt, Co(NO3)2.6H2O, tetra-n-butylammonium salts of PW11CoO593−(PW11CO) and CoW12O40−6(CoW12) heteropolyanions (HPA), CoNaY zeolite, and Co(II) phtalocyanine (CoPc), in alkene epoxidation by the O2/IBA system. It has been found that various alkenes can be converted to the corresponding epoxides with good-to-high selectivity (80%–99%) at complete alkene conversion at ambient conditions. Neither allylic oxidation nor epoxide ring cleavage products were detected for all alkenes tested except for cyclohexene. The nature of catalyst does not considerably affect the selectivity of the epoxidation that depends mainly on the olefin structure. Some decrease of the selectivity was generally observed at high cobalt concentrations. The results obtained in this investigation prove that alkene epoxidation by O2 in the presence of iso-butyraldehyde (IBA) and cobalt catalysts proceeds via radical chain mechanism. Acylperoxy radicals act most likely as the main epoxidizing species although some other species, for example, coordinated to the metal center acylperoxy radicals, may contribute into the epoxidation process when catalysts with low redox potentials are used. Superior catalytic activity of cobalt compounds in alkene epoxidation by O2/IBA system is because of the high ability of cobalt to catalyze the chain branching and promote the chain initiation rather than the ability of cobalt to activate dioxygen via its coordination.

References (39)

  • T. Katsuki

    Coord. Chem. Reviews

    (1995)
  • S. Bhatia et al.

    Tetrahedron

    (1993)
  • P. Mastrorilli et al.

    J. Mol. Catal.

    (1994)
  • P. Mastrorilli et al.

    Tetrahedron

    (1995)
  • N. Mizuno et al.
  • O.A. Kholdeeva et al.

    J. Mol. Catal. A

    (1996)
  • E. Bouhlel et al.

    Tetr. Lett.

    (1993)
  • P. Laszlo et al.

    Tetr. Lett.

    (1993)
  • J. Haber et al.

    J. Mol. Catal.

    (1989)
  • C.L. Hill et al.

    J. Am. Chem. Soc.

    (1986)
  • R.A. Sheldon et al.

    Metal-Catalyzed Oxidations of Organic Compounds

    (1981)
  • K.A. Jorgensen

    Chem. Rev.

    (1989)
  • B. Meunier

    Chem. Rev.

    (1992)
  • N.M. Emanuel et al.

    Chain Reactions of Hydrocarbon Oxidation in Liquid Phase

    (1965)
  • T. Yamada et al.

    Bull. Chem. Soc. Jpn.

    (1991)
  • T. Takai et al.

    Bull. Chem. Soc. Jpn.

    (1991)
  • T. Mukaiyama et al.

    Bull. Chem. Soc. Jpn.

    (1995)
  • R.V. Kucher et al.

    Co-oxidation of Organic Compounds in Liquid Phase

    (1989)
  • Cited by (14)

    • Aerobic epoxidation of limonene using cobalt substituted mesoporous SBA-16 Part 1: Optimization via Response Surface Methodology (RSM)

      2020, Applied Catalysis B: Environmental
      Citation Excerpt :

      Thus, in principle, this process could also be the rate limiting process. Similar dependencies observed by Kholdeeva [66] and Wentzel [55] for the effect of Co(II) and Ni(II) concentrations on oxidation rates were given another explanation. These authors suggested that increasing the amount of Co catalyst inhibited the reaction owing to its participation in chain termination which would prevent the formation of the cobalt-peroxo radical species or convert it into a non-radical peroxo anion.

    • Synthesis and post-metalation of a covalent-porphyrinic framework for highly efficient aerobic epoxidation of olefins

      2017, Catalysis Communications
      Citation Excerpt :

      The TON reached to 29,215 without loss of the catalytic activity in the following runs. It has been well known that the aerobic oxidation of olefins with IBA proceeds through a peroxyl radical mechanism [31,32]. At first, cobalt-porphyrin reacts with IBA to generate an acyl radical [(CH3)2CHC(O)], which would react with O2 to produce an acylperoxy radical [(CH3)2CHC(O)OO] to realize molecular oxygen activation.

    • Aerobic oxidations of α-pinene over cobalt-substituted polyoxometalate supported on amino-modified mesoporous silicates

      2007, Journal of Catalysis
      Citation Excerpt :

      Importantly, this method can be applied even for the production of acid-sensitive epoxides. The selective α-pinene epoxidation via co-oxidation with branched aliphatic aldehydes has been reported to proceed efficiently in the presence of both homogeneous Ni(II) and Co(II) catalysts [11,14,25,26,33,38], as well as over solid CoNaY [39]; however, the latter was not stable with respect to leaching of cobalt under the reaction conditions. Transition metal-substituted polyoxometalates are attracting much attention as oxidation catalysts because of their numerous unique properties, including metal oxide-like structure and thermodynamic stability to oxidation [40–49] and their ability to be supported on different porous materials [50–61], for example, attached to NH2-modified silica surfaces by dative [55] or electrostatic binding [51,54,61].

    • Polyoxometalates: Reactivity

      2004, Comprehensive Coordination Chemistry II
    View all citing articles on Scopus
    View full text