Bioinspired copper corrole and porphyrin catalysts for oxidation and hydrocarboxylation of alkanes

• Molecular design, synthesis, and characterization of new copper corrole and porphyrine complexes. • Application of the obtained compounds as bioinspired homogeneous catalysts in the mild oxidative functionalization of cycloalkanes. • Cu-catalyzed oxidation of cycloalkanes into a mixture of cyclic ketones and alcohols. • Cu-catalyzed hydrocarboxylation of cycloalkanes to cycloalkanecarboxylic acids. • Investigation of selectivity features, substrate and oxidant scope, and effects of various reaction parameters. The development of novel bioinspired catalytic systems that are efficient in the mild oxidative transformation of alkanes remains an attractive research direction in the area of molecular catalysis. In the current study, three copper corrole/porphyrin complexes were synthesized, characterized, and evaluated as homogeneous catalysts in the oxidative transformation of cycloalkanes under mild conditions. New copper complexes of 5,10,15-tris(pentafluorophenyl)corrole and 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin derivatives bearing a hydroxyethoxy unit were obtained via the controlled nucleophilic substitution of para fluorine atom with ethylene glycol. The model catalytic processes include: (i) the oxidation of cycloalkanes with H 2 O 2 into a mixture of cyclic ketones and alcohols, and (ii) the hydrocarboxylation of cycloalkanes in the CO/S 2 O 8 2− /H 2 O system to generate cycloalkanecarboxylic acids as main products. Both model reactions occur under mild conditions (50−60 °C). Selectivity features, substrate and oxidant scope, and the effects of various reaction parameters were studied and discussed. The best catalysts were the copper corrole derivatives, the performance of which is slightly influenced by the presence of the ethylene glycol moiety. In particular, the copper(III) complex of 5,10,15-tris(pentafluorophenyl)corrole is an efficient catalyst for the mild oxidation and carboxylation of cycloalkanes. This work widens the types of Cu-based corrole/porphyrin derivatives that can be used as bioinspired catalytic systems.