Late transition metal nanoparticles: synthesis and catalytic reactivity in wet medium

Seminar

Title: Late transition metal nanoparticles: synthesis and catalytic reactivity in wet medium

Speaker: Montserrat  Gómez

Affiliation: Laboratoire Hétérochimie Fondamentale et Appliquée, UMR CNRS 5069, Université Paul Sabatier, Toulouse, France.

Host: Beatriz Royo - Homogeneous Catalysis Laboratory

Abstract

The decomposition of organometallic precursors under appropriated conditions represents an elegant synthetic methodology to give metallic nanoparticles with a defined composition (1). The key point to obtain nanoparticles with the adequate size and composition for their subsequent applications, is the matching between the molecular precursor and stabilizers.

Our research is focused on the catalytic applications of metallic nanoparticles, in particular in selective processes. I will discuss the catalyst nature when metallic nanoparticles are involved as catalytic precursors,(2) because these systems are placed at the frontier between classical homogeneous and heterogeneous catalysts (3).

In particular, I will present the application of palladium nanoparticles in enantioselective allylic alkylation (4)drogenation and in Suzuki C-C coupling in ionic liquid (5).

Obviously, comprehension of the interaction of the stabilizer with the surface is essential to understand the catalytic behaviour observed. In the last time, we have been interested in the full characterization of palladium and ruthenium nanoparticles, including the characterization of the ligand present in the nanocluster. In addition to the usual techniques employed for nanomaterials characterization (Transmission Electronic Microscopy, IR spectroscopy, elemental analysis), we have carried out several NMR experiences, both in solution and solid state, to study the evolution of the ligand during the nanoparticles formation (6).

1. Philippot, K.; Chaudret, B. C.R. Chimie 2003, 6, 1019.
2. Favier, I.; Gómez, M. Chapter 31 “Metal Nanoparticles Dispersed in Solution: Tests to Identify the Catalyst Nature” in Metal Nanoclusters in Catalysis and Materials Science: The Issue of Size Control, Eds. B. Corain, G. Schmid and N. Toshima, Elsevier, Amsterdam, 2008.
3. Astruc, D.; Lu, F.; Ruiz Aranzaes, J. Angew. Chem. Int. Ed. 2005, 44, 7852.
4. a) Jansat, S.; Gomez, M.; Philippot, K.; Muller, G.; Guiu, E.; Claver, C.; Castillón, S.; Chaudret, B. J. Am. Chem. Soc. 2004, 126, 1592. b) Favier, I.; Jansat, S.; Gómez, M.; Muller, G.; Axet, M. R.; Castillón, S.; Claver, C.; Jansat, S.; Philippot, K.; Chaudret, B. Adv. Synth. Catal. 2007, 349, 2265.
5. a) J. Durand, E. Teuma, F. Malbosc, Y. Kihn, M. Gómez, Catal. Commun. 2008, 9, 273-275; b) F. Fernández, B. Cordero, J. Durand, G. Muller, F. Malbosc, Y. Kihn, E. Teuma and M. Gómez, Dalton Trans. 2007, 5572.
6. Favier, I.; Massou, S.; Teuma, E.; Philippot, K.; Chaudret, B.; Gómez, M. Chem. Commun. 2008, 3296; b) Durand, J.; Fernández, F.; Barrière, C.; Teuma, E.; Gómez, K.; González, G.; Gómez, M. Magn. Reson. Chem. 2008, 46, 739.