Structural and mechanistic studies of co-ordination compounds. Part 26. Synthesis and characterization of some octahedral complexes of ruthenium-(II) and -(III) with macrocyclic quadridentate thioethers

Abstract

A series of ruthenium-(II) and -(III) complexes of the macrocyclic quadridentate thioethers 1,4,8,11-tetrathiacyclotetradecane (L1) and 1,4,7,10-tetrathiacyclotridecane (L2) has been prepared and characterized. Complexes containing the 14-membered ring, L1, viz. trans-[RuL1X2]+ (X = Cl or Br), trans-[RuL1X2] (X = Cl, Br, I, NCS, N3, or NO2), and trans-[RuL1X(OH2)]+ (X = Cl or Br), have the two remaining unidentate ligands trans to each other. However, the 13-membered ring, L2, co-ordinates to the central metal ion in a folded manner to give cis-[RuL2Cl2]+, cis-[RuL2X2] (X = Cl, Br, I, NCS, NO2, or N3), and cis-[RuL2Cl(OH2)]+. All the ruthenium(III) complexes are low spin and the ruthenium(II) complexes diamagnetic. They are all monomeric species. The electronic and i.r. absorption spectra of these complexes are discussed.