Organometallic compounds with N-substituted 3-hydroxy-2-methyl-4-pyridone ligands: square planar rhodium(I), iridium(I), and palladium(II) complexes

Reactions of [(OC)(2)MCl](2) (M = Rh, Ir) or [(cod)RhCl](2) with the anions of N-Aryl or N-Alkyl substituted 3-hydroxy-2-methyl-4-pyridones (O-O') yie ld complexes of the general formula [L2M(O-O')]. Compounds of this type are also available from reactions of [(OC)(2)Rh(acac)] with the corresponding neutral ligands. Substitution of one carbonyl-ligand of the N-phenyl comple x [(OC)(2)Rh(C12H10NO2)] (2) with cyclooctene affords [(OC)(C8H14)Rh(C12H10 NO2)] (8). The palladium complexes [(R3P)Pd(O-O')Cl] (R = Et, Bu), [(C6H4CH 2NMe2) Pd(O-O')] and [(Et3P)(2)Pd(O-O')]BF4 (9-12) were synthesized from [( R3P)PdCl2](2), [(C6H4CH2NMe2)PdCl](2) or [(Et3P)PdCl2]. The structures of t he N-methyl compounds [(OC)(2)Rh(C7H8NO2)] (1) and [(Ph3P)Pd(C7H8NO2)Cl] (9 ) were determined by single crystal X-ray diffraction.