Oxidation of saturated hydrocarbons with hydrogen peroxide, catalysed by titanium silicalite

Abstract

Titanium silicalite catalyses the oxidation of alkanes, alkylbenzenes, 1-chlorohexane, and methyl heptanoate with hydrogen peroxide, at very mild conditions. The reaction may be performed in water, acetonitrile, methanol and t-butyl alcohol, below 55°C. In the latter two solvents, the reaction is faster. Alcohols and ketones are formed at secondary and tertiary sites of the alkyl chain. Yields vary in a wide range of values, according to reaction conditions and to the nature of substrates. With n-hexane, yields higher than 90% on hydrogen peroxide can be observed. The rate of the reaction is strongly affected by acids and bases which are added to the reaction mixture. Some aspects of the reaction mechanism and the properties of the active species are discussed.