Gallium-containing polymer brush film as efficient supported Lewis acid catalyst in a glass microreactor

Beilstein Journal of Organic Chemistry

Willem Verboom¹  Jurriaan Huskens¹  Roberto Ricciardi¹  Richard J. M. Egberink¹  Rajesh Munirathinam¹  Herbert Wormeester²  Michael Holtkamp³  Uwe Karst³ 

[1] Laboratory of Molecular Nanofabrication, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands;Laboratory of Physics of Interfaces and Nanomaterials, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands;University of Münster, Institute of Inorganic and Analytical Chemistry, Corrensstr. 28/30, 48149 Münster, Germany,;

关键词: dehydration of oximes;    flow chemistry;    gallium;    microreactors;    Lewis acid catalysis;    polymer brushes;   

DOI  :  10.3762/bjoc.9.194

来源: DOAJ

【 摘 要 】

Polystyrene sulfonate polymer brushes, grown on the interior of the microchannels in a microreactor, have been used for the anchoring of gallium as a Lewis acid catalyst. Initially, gallium-containing polymer brushes were grown on a flat silicon oxide surface and were characterized by FTIR, ellipsometry, and X-ray photoelectron spectroscopy (XPS). XPS revealed the presence of one gallium per 2–3 styrene sulfonate groups of the polymer brushes. The catalytic activity of the Lewis acid-functionalized brushes in a microreactor was demonstrated for the dehydration of oximes, using cinnamaldehyde oxime as a model substrate, and for the formation of oxazoles by ring closure of ortho-hydroxy oximes. The catalytic activity of the microreactor could be maintained by periodic reactivation by treatment with GaCl3.

【 授权许可】

Unknown