Design and synthesis of multidentate ligands via metal promoted C–N bond formation processes and their coordination chemistry

This presentation reports some novel examples of organic ring amination reactions via metal mediation. The organic transformations are highly regioselective and can be controlled by the proper selection of the mediator complex. The two isomeric organic ligands viz. HL^1 and HL^2 were isolated in their pure states by the removal of the metal ions. These were fully characterized. The ligand HL^1 has low pKa, 8,5. Upon deprotonation, it behaves as a potential bis chelating N,N,N-donors. The coordination chemistry of the HL^1 ligand involving some 3d-metal ions is described. Two unusual low-spin complexes of manganese(II) and iron(III) are reported. The ferric complex displayed a rhombic EPR while, the corresponding manganese compound showed a complex pattern due to hyperfine coupling. All the complexes displayed large number of redox responses. A brief mention about the future projection of this work is noted.