Studies of V(III) complexes with selected alpha-N-heterocyclic carboxylato NO donor ligands: structure of a new seven-coordinated pentagonal bipyramidal complex containing picolinato ligands

摘要

Some highly stable V(In) complexes involving the biologically important and chemically interesting ONO donor ligand pyridine-2,6-dicarboxylic acid (dipicolinic acid, DPAH(2)) are reported. They include both homo- and heterochelates involving DPAH(2) and some other bidentate chelating ligands and one of them is a new highly stable seven-coordinated mononuclear V(III) complex, [V(DPA)(PA)(H2O)(2)]. H2O 4 (PA = picolinate anion). The complex 4 containing two different alpha-N-heterocyclic carboxylates has a pentagonal bipyramidal structure with the equatorial plane accommodating the ONO and NO donor points while the two water molecules occupy the axial positions. [References: 55]