SYNTHESIS AND MOLECULAR-STRUCTURE OF DINUCLEAR AND MONONUCLEAR SCHIFF-BASE PHENOLATE COMPLEXES - FACILE FORMATION OF CYCLOMETALATED RUTHENIUM COMPLEXES

Condensation of 2,6-diformyl-4-methylphenol with aliphatic diamines, N H2(CH2)(n)NH2 (n = 2-4) in the presence of [Ru(dmso)(4)Cl-2] (dmso = d imethyl sulfoxide) resulted in acyclic dinuclear six-co-ordinate ruthe nium(II) complexes [Ru2L(dmso)(4)Cl-4]. The crystal structure of a rep resentative complex was determined; However these reactions in the pre sence of PPh3 gave four-membered cyclometallated dinuclear complexes [ Ru2L'(PPh3)(4)(CO)(2)Cl-2). Compounds formed by condensation of 2,6-di formyl-4-methylphenol with aromatic monoamines reacted with [Ru(dmso)( 4)Cl-2]-PPh3 to give cyclometallated mononuclear ruthenium(II) complex es. The structure of a representative complex was determined. The faci le formation of cyclometallated ruthenium complexes is rationalised.