Complexes of ruthenium with tridentate [P,N,O] ligands

Abstract

Tridentate ligands with [P,N,O] donor sets, prepared either by the condensation of 2-(diphenylphosphino)benzaldehyde with 1S,2R-norephedrine (HL¹) or 2-aminophenol (HL²) or by the condensation of 2-(diphenylphosphino)aniline with salicylaldehyde (sal) (HL³), 5-(NO₂)sal (HL⁴), 5-(Cl)sal (HL⁵), 5-(Br)sal (HL⁶), 5-(MeO)sal (HL⁷) or 3-(MeO)sal (HL⁸), reacted with [Ru^IICl₂(dmso)₄] in refluxing thf solution to yield complexes of the general formula cis-[Ru^IICl(η³-L^1–8)(dmso)₂]. Use of two equivalents of ligand HL¹ resulted in the formation of mer-[Ru^II(η³-L¹)₂], a reaction not seen for HL^2–8. Aerial oxidation of cis,mer-[Ru^IICl(η³-L³)(dmso)₂] in a chloroform solution yielded cis,fac-[Ru^IIICl₂(η³-L³)(dmso)], which has undergone an unexpected rearrangement of co-ordination geometry.