Green Catalysis REnnes – GREENCARE

Selective oxidations of alkenes are central to chemical industry. By adding value to the transformed molecules, these reactions enable the production of numerous derivatives of interest. More particularly, 1,2-diols formation from alkenes and their oxidative cleavage are both industrial reactions, applied to the production of synthetic intermediates, plasticizers, lubricants, monomers and cosmetic and pharmaceutic ingredients. Although very efficient, the current processes used for oxidation of alkenes into diols and their oxidative cleavage are strongly criticized due to the major industrial risk they represent. The reagents required by these conventional processes are expensive, highly toxic and very polluting. Among them, osmium is the second rarest element in Earth crust and displays a toxicity even higher than mercury. Ozone, another reagent used under high temperature and pressure for the oxidative cleavage of alkenes, is highly explosive, as demonstrated by several recent industrial accidents.
Based on the expertise of both partners in homogeneous & heterogeneous catalysis and in green chemistry, the GreenCARE LabCom brings together University of Rennes 1 and Demeta company in order to develop new catalytic methodologies for greener oxidations of alkenes, taking into account this concept at an early stage in the academic research approach. As Demeta will industrialize the technological outcomes of this joint research work, a constant attention will be given to the industrial transfer of processes. More particularly, the research and development of novel oxidation catalysts, based on inexpensive, low toxicity and earth-abundant transition metals, will be targeted to develop greener industrial processes.
To solve such problematic, a special focus will be done on polymetallic catalysis. Indeed, synergies resulting from the association between complementary metals within the same catalyst can boost the reaction productivity and lead to selectivities totally different from those observed in monometallic catalysis. Polymetallic catalysis is a fast-growing concept and is becoming a field of international competition. Polymetallic catalysis is thus an emerging tool having a high potential to substitute critical processes by new sustainable alternatives.
The research strategy of the GreenCARE LabCom will go through the following axes of joint work:
1) Design of novel catalysts based on earth-abundant and low toxicity metals, thanks to the sharing of technical skills from UR1 and Demeta. Access to facilities and research platforms of UR1 will enable the synthesis of candidate catalysts, which will be tested in model conditions of alkene dihydroxylation then oxidative cleavage of diols.
2) Incorporation of the previously identified active species within a same polymetallic bifunctional catalyst, for oxidative cleavage of alkenes, as an alternative to ozonolysis. In order to ensure their industrial compatibility, the catalytic structures will be produced in pre-industrial conditions, thanks to facilities shared by Demeta (high temperatures oven, MP-AES analysis).
3) Implementation of the new oxidation technologies to the valorization of levoglucosenone (LGO), a biobased molecule, for the synthesis of novel fine chemicals with high added value (fragrances, flavors, cosmetic ingredients), produced and commercialized by Demeta.
Research outcomes of the GreenCARE LabCom will thus enable the definitive substitution of criticized oxidation processes (ozonolysis and osmium) by implementing innovative catalytic technologies, combining sustainability and industrial productivity.