THE KINETICS AND MAIN PATHWAYS FOR THE LIQUID-PHASE OXIDATION OF CYCLOHEXENE BY AIR IN THE PRESENCE OF COBALT, CHROMIUM, IRON, AND NICKEL MU3-OXOTRIMETALLOHEXAPIVALATES

It was found that during the liquid-phase oxidation of cyclohexene (CH) by air (323-343 K) in the presence of a series of homo- and heteronuclear ,MU3-oxotrimetallohexapivalates with a M2M´O (M, M´ = Co, Cr, Fe, Ni) core insignificant amounts of the corresponding epoxide are formed, and 3-hydroperoxy-2-cyclohexene (HP), 3-hydroxy-2-cyclohexene (CHol), and 2-cyclohexen-3-one (CHone) accumulate in the oxidate. It is suggested that CHone and CHol are “dead-end” products from the oxidation of CH under the investigated conditions while the HP is a unique “intermediate–damper” that gives rise to the realization of alternative paths (catalytic cycles) for the formation of these products.