Rational Design of Fluorinated Environments for Aerobic 'Green' Catalysis

0967934

Barat

The work which will be conducted by Profs. Barat and Gorun at New Jersey Institute of Technology is to design active catalyst species which are in essence miniature reaction vessels. This feature makes them similar to enzyme catalyst sites. The PIs intend to use perfluorinated phthalocyanines as hydrophobic vessels surrounding hydrophilic metal centers for the aerobic oxidation of mercaptans to disulfides. These perfluorinated phthalocyanines should be more resistant to damage by catalytically-produced oxygen radicals than other oxidation catalysts, which is another feature in common with enzymes. The work proposed is a straightforward study of the influence of ligand structure on catalyst activity, and stability. The authors propose to study the kinetics of the homogeneous radical-based oxidation, as well as evaluating heterogenized versions of the catalyst (Cobalt-based phthalocyanines coordinated to SiO2 through imidazolyl groups).

The project aims to provide catalysts for oxidation of molecules which are more 'green' than previous catalysts by allowing the use of air for the reaction without the catalyst being destroyed by the oxygen. This is done by replacing reactive C-H bonds with unreactive C-F bonds in the catalyst species. Further fine tuning of the catalyst is possible by using organic chemistry modifications of the catalyst. The investigators have chosen mercaptan oxidation, now used to remove sulfur from gasoline, as the first reaction for study. This is a useful benchmark, and success will allow projection of the concept to other catalysts and reactions. These studies will be of interest to the community enrolling at NJIT, and the PIs will involve undergraduates in the research program.