Palladium Nanoparticles Bonded to Two‐Dimensional Iron Oxide Graphene Nanosheets: A Synergistic and Highly Reusable Catalyst for the Tsuji–Trost Reaction in Water and Air. Issue 36 (22nd July 2014)

• Record Type: Journal Article
• Authors: Liu, Jian; Huo, Xing; Li, Tianrong; Yang, Zhengyin; Xi, Pinxian; Wang, Zhiyi; Wang, Baodui
• Is Part Of: Chemistry. Volume 20:Issue 36(2014)
• Page Start: 11549
• Page End: 11555
• Publication Date: 2014-07-22
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201402545
• Languages: English
• ISSNs: 0947-6539

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Low cost, high activity and selectivity, convenient separation, and increased reusability are the main requirements for noble‐metal‐nanocatalyst‐catalyzed reactions. Despite tremendous efforts, developing noble‐metal nanocatalysts to meet the above requirements remains a significant challenge. Here we present a general strategy for the preparation of strongly coupled Fe<sub>3</sub>O<sub>4</sub> and palladium nanoparticles (PdNPs) to graphene sheets by employing polyethyleneimine as the coupling linker. Transmission electron microscopic images show that Pd and Fe<sub>3</sub>O<sub>4</sub> nanoparticles are highly dispersed on the graphene surface, and the mean particle size of Pd is around 3 nm. This nanocatalyst exhibits synergistic catalysis by Pd nanoparticles supported on reduced graphene oxide (rGO) and a tertiary amine of polyethyleneimine (Pd/Fe<sub>3</sub>O<sub>4</sub>/PEI/rGO) for the Tsuji–Trost reaction in water and air. For example, the reaction of ethyl acetoacetate with allyl ethyl carbonate afforded the allylated product in more than 99 % isolated yield, and the turnover frequency reached 2200 h<sup>−1</sup>. The yield of allylated products was 66 % for Pd/rGO without polyethyleneimine. The catalyst could be readily recycled by a magnet and reused more than 30 times without appreciable loss of activity. In addition, only about 7.5 % of Pd species leached off after 20 cycles, thus rendering this catalyst safer for the environment.</p> </abstract>