New palladium α-diimine complexes containing dendritic wedges for ethene oligomerisation

The synthesis, characterisation and catalytic behaviour of new palladium α-diimine complexes containing zero and first generation dendritic wedges is described. A para-hydroxyl functionality in α-diimine ligands was used to attach dendritic wedges. The resulting ligands were reacted with (COD)PdCl2 to give the corresponding palladium α-diimine complexes. These complexes were used for the catalytic oligomerisation of ethene and are compared to a related nickel system. The complexes are active catalysts for the oligomerisation of ethene in the presence of MAO as a co-catalyst.