title: A smart palladium catalyst in ionic liquid for tandem processes.
abstract: New catalytic systems based on in situ and preformed palladium nanoparticles in ionic liquids (characterised by TEM) starting from palladium acetate or dipalladiumtris(dibenzylideneacetone) have been applied in the synthesis of 4-phenylbutan-2-one (II), a model compound for the preparation of fragrances. Imidazolium-based ionic liquid containing a methyl hydrogenophosphonate anion leads to an efficient Pd-catalyzed tandem coupling/reduction process, taking advantage of the multi-role of this solvent (nanoparticles stabiliser, base, hydrogen transfer agent). The influence of the mono-phosphine ligands (1-3) on the catalyst has been evaluated, showing that the ligand-free palladium system turns into the most appropriate for the formation of II using Pd(OAc)(2) as precursor. Fine-tuning conditions involved in this multi-parameter process have led us to propose a plausible mechanism based on the hydrogen transfer coming from the methyl hydrogenophosphonate anion.
authors.affiliation: Université de Toulouse, UPS, LHFA, 118 route de Narbonne, F-31062 Toulouse Cedex 9, France.
authors.forename: Eva
authors.initials: E
authors.lastname: Raluy
authors.forename: Isabelle
authors.initials: I
authors.lastname: Favier
authors.forename: Angela M
authors.initials: AM
authors.lastname: López-Vinasco
authors.forename: Christian
authors.initials: C
authors.lastname: Pradel
authors.forename: Erika
authors.initials: E
authors.lastname: Martin
authors.forename: David
authors.initials: D
authors.lastname: Madec
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Teuma
authors.forename: Montserrat
authors.initials: M
authors.lastname: Gómez