A conceptual DFT study of chemical reactivity of pyridine dicarboxamide compounds

One of the significant point of the coordination chemistry is the evaluation of the reactivity ofdifferent reaction centers within a molecule as a ligand [1,2]. As a part of our systematicinvestigations on the coordination behavior of pyridine dicarboxamide derivatives as neutraland anionic forms we designed, synthesized and structurally characterized three new pyridinedicarboxamide ligands with 2-aminopyrimidine (L0H2), 2-amino-4-methylpyrimidine (L1H2)and 2-amino-4,6-dimethylpyrimidine (L2H2). Coordination sites of this kind of pincer ligandsstrongly depend on the charge of ligand [3]. The coordination ability has been increased bylosing proton of amide groups. In this case, N atom of pyridine ring and two N atoms ofamidate groups connect to a metal center and create two five membered chelating rings [4].For investigation and validity of experimental observations on the reactivity of this kind ofcompounds (neutral and doubly deprotonated forms), reactivity indices such as global andlocal hardness/softness, electophilicity, electronegativity, Fukui functions have beencalculated within conceptual DFT rules and Pearson's hard and soft acid and base principle[4].