Preparation and Crystal Structures of Manganese, Iron, and Cobalt Complexes of the Bis[di(2-pyridyl)methyl]amine (bdpma) Ligand and Its Oxidative Degradation Product 1,3,3-Tris(2-pyridyl)-3H-imidazo[1,5-a]pyridin-4-ium (tpip); Origin of the bdpma Fragility
作者:Catherine Hemmert、Michael Renz、Heinz Gornitzka、Stéphanie Soulet、Bernard Meunier
DOI:10.1002/(sici)1521-3765(19990604)5:6<1766::aid-chem1766>3.0.co;2-z
日期:1999.6.4
The synthesis and structural characterization of manganese, iron, and cobalt complexes of bis[di(2-pyridyl)methyl]amine (bdpma) were investigated. The bdpma ligand can give rise to mono- or dimeric complexes. Moreover, bdpma can undergo oxidative degradation leading to 1,3,3-tris(2-pyridyl)-3H-imidazo[1,5-a]pyridin-4-ium (tpip) or to starting materials used for the preparation of bdpma. During attempts to prepare manganese, iron, or cobalt complexes of the tpip ligand, two classes of compounds were obtained. The first class corresponded to the tpip cation with a simple exchange of counterion and the second class led to a new type of complex, which involved a modification of tpip and contained the N-(di(2-pyridyl)methoxymethyl)(di(2-pyridyl)imine) (dpmmdpi) ligand. This work has allowed us to understand the fragility of the bdpma ligand, which is due to the easily activated benzylic C-H bonds in the a position to the heteroatom.