Selective Aerobic Oxidation of Benzyl Alcohols with Palladium(0) Nanoparticles Suspension in Water

• Published in: Catalysis letters Vol. 151; no. 11; pp. 3239 - 3249
• Main Authors: Bourbiaux, Dolorès, Mangematin, Stéphane, Djakovitch, Laurent, Rataboul, Franck
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.11.2021; Springer; Springer Nature B.V; Springer Verlag
• Subjects: Alcohols; Aldehydes; Benzyl alcohol; Catalysis; Catalysts; Chemical Sciences; Chemistry; Chemistry and Materials Science; Industrial Chemistry/Chemical Engineering; Lignin; Nanoparticles; Organic chemistry; Organometallic Chemistry; Oxidation; Oxidation-reduction reaction; Palladium; Physical Chemistry; Povidone; Stabilizers (agents); Substrates; Titanium dioxide; Vanillin; Veratryl alcohol; Alcohols oxidation; Aqueous suspension; Catalysis; Metallic nanoparticles
• ISSN: 1011-372X; 1572-879X
• DOI: 10.1007/s10562-021-03581-0

This study concerns one of the rare applications of a suspension of palladium nanoparticles in water for oxidation reactions. The aqueous suspension containing well dispersed nanoparticles of 3.85 nm was obtained following a straightforward procedure involving the reduction of Na 2 PdCl 4 with NaBH 4 in the presence of PVP as stabilizing agent. In the way of oxidative catalytic valorisation of lignin, the aqueous suspension was directly applied as catalytic medium for the selective oxidation of vanillic alcohol into vanillin (80 °C, O 2 , 1 h) with more than 90% yield. Reusability of the catalytic medium has been demonstrated, acting as “quasi-homogeneous catalyst”. More sophisticated lignin-derived substrates like veratryl alcohol and hydrobenzoin gave yields of 50–80% to the respective aldehyde and ketone. In parallel, this as-synthesized suspension was directly used to prepare a Pd/TiO 2 catalyst, the latter showing less efficiency for the catalytic transformations. Graphic Abstract