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A catalyst precursor prepared in situ from palladium acetate and a phosphine ligand was used for the Stille cross-coupling reaction of benzylic bromides and chlorides with aryltributyltin analogues. The reactions were performed at 80 °C using dppf as ligand in the presence of KF, or more conveniently using PPh 3 in the absence of base, furnishing diarylmethane derivatives in high yields (86–99%). Using Pd(OAc) 2 /PPh 3 as catalyst precursor competitive Stille and Suzuki cross-coupling reactions with benzyl chloride showed that in the absence of base or in the presence of KF the Stille product is the majority product, and only the Suzuki product was obtained in the presence of KOH as base.

A simple catalyst precursor prepared in situ from palladium acetate and triphenylphosphine shows high activity for the Suzuki cross-coupling reaction of benzylic bromides and chlorides with aryl boronic acids. The reaction can be carried out at low catalyst loading (0.002–1 mol%) and under mild conditions (room temperature to 80 °C) furnishing diarylmethane derivatives in high yields (86–99%).

The palladium-catalyzed hydroesterification of styrene derivatives is performed in a two-phase system composed of 1-n-butyl-3-methylimidazoliumtetrafluoroborate salt (ionic phase) and isopropanol/cyclohexane (organic phase). Very high regioselectivities in 2-arylpropionic esters (≥99.5%) are obtained using a catalytic system composed of PdCl2(PhCN)2, (+)-neomenthyldiphenylphosphine (NMDPP) and p-toluenesulfonic acid under mild reaction conditions (10 atm and 70°C).

The synthesis of 3-aryl-1-butenes is performed by hydrovinylation of styrene and alkylsubstituted styrenes catalyzed by [Ni(MeCN)6][BF4]2/Et2AlCl/PPh3 under mild conditions with very good activities and selectivities.

Aryl bromides and iodides can be coupled with phenylboronic acid in good yields using NiCl2·6H2O as a catalyst precursor. This nickel complex is cheap, widely available and can be used without any auxiliary ligand or reducing agent.