Halfsandwich complexes of ruthenium(II), rhodium(III) and iridium(III) with N-substituted 3-hydroxy-2-methyl-4-pyridone ligands

The synthesis and characterization of (p-cymene)Ru-II, Cp*Rh-III and Cp*Ir-III complexes with N-alkyl and N-aryl substituted 3-hydroxy-2-methyl-4-pyridone ligands is reported. All compounds display an unusually high solubility in water. With the chiral ligand N-(o-C6H4CO2Me)-3-hydroxy-2-methyl-4-pyridone two isomers were obtained but no diastereoselectivity was observed. The structure of [(p-cymene)Ru(C9H12NO2)Cl] (2) was determined by single crystal X-ray diffraction. Reactions of [p-cymene) Ru(C7H8NO2)Cl] (1) with n-butylamine and triphenylphosphine were shown to result in substitution of the chloride ligand. (C) 1999 Elsevier Science S.A. All rights reserved.