Palladium-alumina chloride complexes

However, the generation of thin palladium membranes onto ceramic surfaces is more complicated. Methods such as spray pyrolysis (see also Section 4.1.3), chemical vapour deposition and sputtering are used. Another method commonly applied [400] is electroless plating [408]. Palladium particles are produced from palladium solution containing amine complexes of palladium in the presence of reducing agents. Palladium nuclei need to be seeded onto the surface prior to the coating procedure [408]. Ceramic surfaces such as a-alumina are first sensitised in acidic tin chloride and then palladium is seeded from acidic palladium ammonia chloride [408]. 

Different conditions (including additives and solvent) for the reaction have been reported,often focusing on the palladium catalyst itself," or the ligand." Catalysts have been developed for deactivated aryl chlorides," and nickel catalysts have been used." Modifications to the basic procedure include tethering the aryl triflate or the boronic acid to a polymer, allowing a polymer-supported Suzuki reaction. Polymer-bound palladium complexes have also been used." " The reaction has been done neat on alumina," and on alumina with microwave irradiation." Suzuki coupling has also been done in ionic liquids," in supercritical... 

Palladium chloride supported on silica gel and "y-alumina are active for the dimerization of ethylene [252]. PdCl2(Me2SO)2 and K PdCl,(MeSO) on KSH-2 silica gel catalyze ethylene dimerization. The yield of dimer and selectivity are high with use of 0.1% dimethylsulfoxide complex precipitated from acetone at 90°C and with 0.3% ionic complex precipitated from chlorobenzene at 100°C [252-255]. 

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