Cleavage of C-O bonds in lignin model compounds catalyzed by methyldioxorhenium in homogeneous phase.

ChemSusChem

Chair of Inorganic Chemistry/Molecular Catalysis, Catalysis Research Center, Technische Universität München, Ernst-Otto-Fischer-Str. 1, 85747 Garching bei München (Germany), Fax: (+49) 89-289-13473.

Published: February 2014

Methyldioxorhenium (MDO)-catalyzed C-O bond cleavage of a variety of lignin β-O-4-model compounds yields phenolic and aldehydic compounds in homogeneous phase under mild reaction conditions. MDO is in situ generated by reduction of methyltrioxorhenium (MTO) and is remarkably stable under the applied reaction conditions allowing its reuse for least five times without significant activity loss. Based on the observed and isolated intermediates, 17 O- and 2 H-isotope labeling experiments, DFT calculations, and several spectroscopic studies, a reaction mechanism is proposed.

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http://dx.doi.org/10.1002/cssc.201300918DOI Listing

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