Tandem ethylene oligomerization and Friedel–Crafts alkylation of toluene catalyzed by hyperbranched nickel complex and ethylaluminium dichloride

New hyperbranched iminopyridyl ligand was synthesized with 1.0 generation hyperbranched polyamidoamine molecule and pyridine-2-carbaldehyde. Reaction of the ligand with NiCl2·6H2O afforded the hyperbranched iminopyridyl nickel complex. The compounds were characterized by IR, UV, 1H NMR, 13C NMR and ESI-MS. The complex upon activation with ethylaluminum dichloride (EtAlCl2) produced a tandem catalyst system that oligomerized ethylene to butene and hexene and subsequently used the olefins present in the reaction medium to alkylate toluene that was used as solvent in the reactions. This led to mono-, di-alkyltoluenes with ethylene, butene and hexene.