Kinetic and Mechanistic Studies on the Reaction of DL-Methionine with [(H2O)(tap)2RuORu(tap)2(H2O)

Abstract

Introduction Isatin (2,3-dihydroindole-2, 3-dione) is a versatile lead molecule for designing potential bioactive agents, and its derivatives were reported to possess broadspectrum antiviral activity [1, 2]. In the previous reports, the synthesis and characterization of group 6 and 8 complexes of isatin and 5-methylisatin in absence and presence of bipyridine were investigated [3, 4]. In this article, we report the synthesis and characterization of molybdenum and tungsten complexes of isatin in the presence of PPh3. e aim of these reactions is the synthesis and study of mixed-ligand complexes, where the metal is surrounded by dierent donor atoms in the coordination sphere, that is, the oxygen from isatin and phosphorous atom from the triphenylphosphine (PPh3). PPh3 is dierent from the carbonyl group since it is a strong σ-donor and weak pi-acceptor ligand. Furthermore, the organic phosphenes increase the stability of the transition metal complexes in the lowoxidation state. Taking into account the electronic spectra the combination of a reducing metal and an acceptor ligand generates a metal-to-ligand charge transfer (MLCT) excited state which may appear in absorption and emission [5, 6].