A new calcium(II) coordination polymer based on a µ₂-bridging tridentate 4-nitrobenzoate

Abstract

Reaction of a heptacoordinated Ca(II) compound [Ca(H₂O)₄(4-nba)₂] (4-nba = 4-nitrobenzoate) with 3,5-dimethyl-pyrazole (dmp) leads to the formation of an eight coordinated Ca(II) compound, [[Ca(H₂O)₂(4-nba)₂]·2dmp]_n, containing two coordinated water molecules, two unique 4-nba ligands and two free dmp molecules in the lattice. The μ₂-bridging tridentate binding mode of the unique 4-nba ligands results in the formation of a one-dimensional (1-D) coordination polymer. The title compound exhibits enhanced fluorescence emission. An analysis of the six different bridging binding modes of the 4-nba ligand in twenty two different structurally characterized 4-nitrobenzoate compounds is described.