Neutral, Cationic, and Zwitterionic Ruthenium(II) Atom Transfer Radical Addition Catalysts Supported by P,N-Substituted Indene or Indenide Ligands

A series of Ru-based complexes supported by P,N-substituted indene or indenide ligands have been prepared and tested for activity in the atom transfer radical addition of CCl4 to alkenes. The catalytic performance was found to be influenced by the charge and substitution pattern of the P,N ligand and other coligands, as well as the nature of the counteranion, with the best of these catalysts being effective at low catalyst loadings and under mild conditions.