Multivariate analysis applied to oxidation of cyclohexane and benzyl alcohol promoted by mononuclear iron and copper complexes

Although univariate methodologies facilitate the interpretation of results, they may not correspond to the ideal conditions for a catalytic process. Herein, we examine the catalytic activity of an iron(iii) (1) and a copper(ii) (2) complex under mild conditions in the oxidation of cyclohexane (Cy) and benzyl alcohol (BnOH) with hydrogen peroxide, following a Box-Behnken multivariate experimental design. To the best of our knowledge, this is the first report of the application of this tool to the homogeneous oxidation of these organic substrates. The multivariate approach allowed a range of optimal conditions to be identified for the variables studied. Complex 1 was able to convert higher amounts of the studied substrates into products when compared with 2. However, 2 presented higher selectivity toward the generation of cyclohexanol (CyOH) and benzaldehyde (BA) than 1, although the conversion rates were lower.