Homogeneous catalysis of aerobic oxidation of alcohols and amines: Biomimetic metal-phenoxyl radical reactivity

• Applicant: Professor Dr. Phalguni Chaudhuri
• Subject Area: Biochemistry
• Term: from 1999 to 2006
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5173740

The proposed work builds on prior results in two major areas of coordination chemistry with phenoxyl-radicals. The first area of proposed project is involved with the preparative coordination chemistry based on the use of easily oxidizable phenolcontaining ligands with transition metal ions. The resulting complexes will be characterized by different spectroscopic methods (UV-VIS, resonance Raman, EPR and eventually Mössbauer), magnetic susceptibility measurements and by X-ray crystallography. Emphasis will be given on the electrochemical redox processes in general and in particular on the electrochemically generated phenoxyl-containing species. In the second area of proposed work we will develop efficient biomimetic catalysts based on the facile formation of phenoxyl radical for aerial oxidation of alcohols and amines. These model catalysts should work on a wider range of substrates and in harsher conditions than enzymes can. Emphasis will be focussed on copper- and iron-containing systems of importance as industrial catalysts. Preliminary results indicate that the use of recently synthesized coordination compounds will uncover a wealth of new knowledge regarding "radicals in the enzymatic catalysis" that includes functional models not only of the copper-containing enzyme galactose oxidase but also of amine oxidases. We will build on this preliminary work to greatly increase the scope of the chemistry of metal-phenoxyl radical. The proposed project is expected to have wide impact on chemical and catalytic science as well as providing excellent learning opportunities in modern inorganic chemistry for students.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1071: Radikale in der enzymatischen Katalyse
• Participating Person: Professor Dr. Karl Wieghardt