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

ABSTRACT: 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.

SUBMITTER: Munirathinam R

PROVIDER: S-EPMC3778416 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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

Munirathinam Rajesh R Ricciardi Roberto R Egberink Richard J M RJ Huskens Jurriaan J Holtkamp Michael M Wormeester Herbert H Karst Uwe U Verboom Willem W

Beilstein journal of organic chemistry 20130816

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-functionali ...[more]

PMID: 24062830

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