Efficient Heterogeneously Palladium-Catalysed Synthesis of Stilbenes and Bibenzyls

Hydrogenation of benzene and toluene over size controlled Pt/SBA-15 catalysts: Elucidation of the Pt particle size effect on reaction kinetics

“…The typical catalysts for such systems are complexes of palladium with various ligands, though often supplied just as Pd(acac) 2 or Pd(PPh 3 ) 4 . The palladium is then oxidized and reduced between Pd 0 and Pd II during the catalytic cycle.…”

“…In addition to organic synthesis (an arena in which such reactions † Current Address: Department of Chemistry, University of California, Berkeley, CA 94720 (USA) Email:beaumont@berkeley.edu 2 have become indispensible since the first homogeneous organometallic reagents appeared about 40 years ago) 2 they have also begun to unlock new strategic approaches for the preparation of materials for use in optical and electronics applications. 3 For example, they have been used in the production of functional stilbenes and bibenzyls for use in liquid crystals 4 or the preparation of conjugated oligomers which can be used in light emitting devices. 5 In the production of fine chemicals and pharmaceuticals, the application of heterogeneous catalysts is especially attractive because of the considerable advantages offered by being able to work in a continuous flow mode, also eliminating the need for subsequent difficult steps to separate catalyst and products.…”

One‐Pot Suzuki/Heck Sequence for the Synthesis of (E)‐Stilbenes Featuring a Recyclable Silica‐Supported Palladium Catalyst via a Multi‐Component Reaction in 1,3‐Propanediol

“…In 2000, GenÞt et al described the first tandem Heck/hydrogenation procedure [5] using a "Lindlar-type" Pd(0)/CaCO 3 catalyst for the synthesis of useful Wadsworth-Emmons reagents. In a similar fashion, Djakovitch and co-workers reported the one-pot preparation of bibenzyls [6,7] using common Pd(0)/C or Pd(II)/C catalysts while Corma et al achieved the synthesis of a fragrance with raspberry scent [8] by exploiting the dual reactivity of an original and recyclable Pd(0)/TiO 2 catalyst. In 2008, Felpin and co-workers reported the first application of Pd(0)/BaCO 3 in a Suzuki/hydrogenation sequence [9] allowing a shortened protocol toward the synthesis of bifenazate; however, in situ decomposition of the support limits to date its potential applications.…”

“…Pursuing our efforts devoted to the application of heterogeneous Pd catalysts [14][15][16][17][18][19][20][21] in one-pot procedures, [7,[22][23][24][25] we have recently disclosed the vinylation of aryl halides through the use of commercially available Pd/C. [26,27] Such compounds are useful intermediates for the synthesis of stilbenes, an important class of biologically relevant molecules including the wellknown resveratrol and combretastatin A-4.…”

Aqueous Heck Arylation of Acrolein Derivatives: The Role of Cyclodextrin as Additive

“…In the literature, several reports described the possibility of using porous supports to immobilize palladium complexes or to support palladium particles for the Heck reaction, including active carbon and metal oxides. [20,21] Palladium catalyst supported on zeolites has shown exceptional activity and stability [22][23][24]. Herein, we will investigate the behavior of Pd/C and [Pd(NH 3 ) 4 ]/NaY catalysts in the Heck arylation of acrolein diethyl acetal.…”