[Pd/Base/QX] catalyst systems for directing Heck-type reactions

Polyionic Gels: Efficient Heterogeneous Media for Metal Scavenging and Catalysis

“…A low yield (46 %) of the coupling product was observed with homogeneous Pd(OAc) 2 (Table 1, (Table 1, entry 3), whereas, as described by Jeffery and David, [15] the presence of soluble ammonium salts (7.0 mol % NBu 4 Cl) increased the yield (65 %, Table 1, entry 5). The coupling reaction carried out with soaked Pd 2 occurred in 79 % yield, thus confirming that polyionic gels provide a particularly appropriate environment for organometallic catalysis.…”

Copper- and ligand-free Sonogashira reaction catalyzed by palladium in microemulsion

“…Recent reports showed that the palladium nanoparticles acted as active catalysts for C-C coupling reactions [11][12][13][14]. The Pd(0) nanoparticles can be formed under reducing agents or sonochemical reactions.…”

Palladate salts from ionic liquids as catalysts in the Heck reaction

“…So, we replaced styrene by 2,3-dihydrofuran 11 and performed the reaction in similar conditions as those previously described. …”

“…ILs are of special interest due to their specific properties: they present good chemical and thermal stability, low vapour pressure, wide liquid range, good solubility for a wide range of organic and inorganic reagents and they allow the facile separation of the products and recycling of the ILs containing the catalysts. 8,9 In addition to this, the use of ILs in the Heck reaction has opened new insights and perspectives: 10 (i) ILs containing imidazolium cations stabilize ligandfree precursors of catalysts (free of η 2 donor ligands such as phosphines), consequently catalysts like palladium acetate proved to be efficient even at low concentrations and have been widely used; 8,11,12 (ii) When performed in ILs, the reaction rate was significantly increased. [13][14][15] In certain cases, this enabled the regioselectivity of the products obtained to be controlled; 16 (iii)…”