BiomCatOx · Biomimetic Dicopper Architecture for Catalytic Oxygen Activation

Biomimetic Dicopper Architecture for Catalytic Oxygen Activation

In the current ecological and economical context (global warming, pollution, waste treatment…) researchers are pushed to develop new industrial processes that are environmental friendly and profitable. In chemistry, syntheses can be very costly in energy, such as the transformation of raw material from natural sources as for example petroleum and gas. Those reactions demand high temperatures and pressure, and conditions that are long and polluting. BiomCatox will develop a new concept for the realization of these reactions in mild conditions, i.e. performing them in water and using dioxygen as a mild oxidant. This will provide a strict control on the reactivity of the process and will improve the efficiency of the synthetic catalyst. BiomCatOx explored a unique catalyst design for the valorisation of hydrocarbons by oxygen insertion into a C–H bond under mild reaction conditions and using O2 as cheap and benign oxidant. The major challenge that needed to be addressed is the control of the activation of O2 into reactive oxygen species (ROS) for selective and catalytic insertion of an oxygen atom into a C–H bond. The key concept of BiomCatOx was to rigorously control the activation of O2 and the formation of metal-based reactive oxygen species (ROS) to accomplish selective and catalytic oxidation of hydrocarbons. The novelty of BiomCatOx lied in the design of the catalyst that consisted in connecting a heavily truncated protein as electron relay for controllable intramolecular electron transfer (IET) to a synthetic oxidation catalyst. The intramolecular electron transfer could be rationally custom-tailored and therefore provides strict control on the reactivity of the catalytic center and on the formation of the ROS. BiomCatOx used a stepwise approach involving (i) the development of copper-NHC complexes as powerful catalysts for the formation of ROS and hydrocarbon oxidation, (ii) the development of a copper peptide derived from the azurin active site for efficient electron transfer, and (iii) the covalent connection of the two copper sites into a peptide-complex dicopper conjugate for controlled intramolecular electron transfer. The implementation of BiomCatOx provided efficient catalytic systems and fundamental insights into O2 activation, and disclosed a new catalyst design concept. The results of this project provides a new strategy for more economic and more sustainable hydrocarbon oxidation catalysis that will benefit the organometallic and bio-inorganic chemistry communities. New oxidation catalysts were designed, synthetic academics and the chemical industry will gain access to new strategies for C–H bond functionalization by O2 activation.

Data: CORDIS, © European Union