Oil soluble catalysts are used to convert polynuclear aromatic compounds in a hydrocarbon feedstock to higher value mono-aromatic compounds. The catalyst complex includes a catalytic metal center that is bonded to a plurality of organic ligands that make the catalyst complex oil-soluble. The ligands include an aromatic ring and a ligand spacer group. The ligand spacer group provides spacing of 2-6 atoms between the metal center and the aromatic ring. The spacing between the aromatic group and the catalytic metal center advantageously allows the catalyst to selectively crack polynuclear aromatic rings while preserving one of the aromatic rings, thereby increasing the content of mono-aromatic compounds in the hydrocarbon feedstock.