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Communication
Aerobic Oxidation of Primary Aliphatic Alcohols to Aldehydes Catalyzed by a Palladium(II) Polyoxometalate Catalyst
Article first published online: 5 FEB 2010
DOI: 10.1002/adsc.200900663
Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Additional Information
How to Cite
Barats, D. and Neumann, R. (2010), Aerobic Oxidation of Primary Aliphatic Alcohols to Aldehydes Catalyzed by a Palladium(II) Polyoxometalate Catalyst. Adv. Synth. Catal., 352: 293–298. doi: 10.1002/adsc.200900663
Publication History
- Issue published online: 17 FEB 2010
- Article first published online: 5 FEB 2010
- Manuscript Revised: 30 DEC 2009
- Manuscript Received: 23 SEP 2009
Funded by
- German-Israeli Project Cooperation. Grant Number: DIP-G7.1
- Israel Science Foundation
- US-Israel Binational Science Foundation
- Kimmel Center for Molecular Design
- Bernice and Roger Cohn Center for Catalysis
Keywords:
- alcohols;
- oxidation;
- oxygen;
- palladium;
- polyoxometalates
Abstract
A hexadecyltrimethylammonium salt of a “sandwich” type polyoxometalate has been used as a ligand to attach a palladium(II) center. This Pd-POM compound was an active catalyst for the fast aerobic oxidation of alcohols. The unique property of this catalyst is its significant preference for the oxidation of primary versus secondary aliphatic alcohols. Since no kinetic isotope effect was observed for the dehydrogenation step, this may be the result of the intrinsically higher probability for oxidation of primary alcohols attenuated by steric factors as borne out by the higher reactivity of 1-octanol versus 2-ethyl-1-hexanol. The reaction is highly selective to aldehyde with little formation of carboxylic acid; autooxidation is inhibited. No base is required to activate the alcohol. The fast reactions appear to be related to the electron-acceptor nature of the polyoxometalate ligand that may also facilitate alcohol dehydrogenation in the absence of base.