Ortho-ruthenation of 1-naphthalenyl in 1-naphthaldehyde 4-R-benzoylhydrazones: Ruthenium(III) CNO pincer complexes

Cycloruthenates trans-[Ru(nabhR)(PPh3)2Cl] are reported. The molecular structures of the one-electron paramagnetic and redox active complexes are established by EPR and X-ray crystallography. Regioselective ortho-ruthenation of 1-naphthalenyl in (nabhR)2− leads to its CNO pincer like binding mode and formation of 5,5-fused chelate rings at the trivalent low-spin metal centre.