Numerous reports revealed that 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) radical and its derivatives are one of the most promising catalysts for selective oxidation of alcohols to their corresponding aldehyde or ketone... [ view full abstract ]
Numerous reports revealed that 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) radical and its derivatives are one of the most promising catalysts for selective oxidation of alcohols to their corresponding aldehyde or ketone analogues. Recently, C60 fullerene was applied as a platform for recyclable alcohol oxidation catalyst based on TEMPO malonate derivative [1,2]. Proposed systems turned out to be highly effective. However, reported procedures suffer from several restitution steps, which limit large scale application.
In contrast, catalytic system based on insoluble support should allow simple removal of catalytic material from reaction mixture. Taking into account chemical stability and various methods for surface functionalization gold was selected to be material of choice. Deposition of thiolate species has been widely used for the chemisorption of desired groups onto Au surface. We recently reported advantageous procedure for in situ deposition of S-acetyl functionalized fullerenes onto gold surface, leading to systems revealing interesting catalytic properties [3,4].
In this cotribution we present synthesis, characterization and catalytic studies of novel TEMPO functionalized C60 fullerene derivative grafted onto surface of gold powder. Obtained catalyst was characterized using electron spin resonance (ESR) spectroscopy, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), cyclic voltammetry (CV) and thermogravimetric analysis (TGA). Proposed catalytic system was successfully employed for selective oxidation of selected alcohols to their carbonyl derivatives.
[1] H. A. Beejapur, F. Giacalone, R. Noto, P. Franchi, M. Lucarini, M. Gruttadauria, Chem. Cat. Chem. 5 (2013) 2991 –2999.
[2] H.A. Beejapur, V. Campisciano, P. Franchi, M. Lucarini, F. Giacalone, M. Gruttadauria, Chem. Cat. Chem. 6 (2014) 2419- 2424.
[3] P. Piotrowski, J. Pawłowska, J. Pawłowski, A. Więckowska, R. Bilewicz, A. Kaim, J. Mater. Chem. A 2 (2014) 2353-2362.
[4] P. Piotrowski, J. Pawłowska, J. Pawłowski, A. M. Czerwonka, R. Bilewicz, A. Kaim, RSC Adv. 5 (2015) 86771- 86778.
Carbon & graphene nanostructures , Nanocatalysis & applications in the chemical industry
