On the syntheses and structures of two calcium coordination polymers containing terminal amide ligands

Abstract

The syntheses and crystal structure of the calcium coordination polymers [Ca(NMF)sub(2) (4-nba)sub(2)] 1 (4-nba = 4-nitrobenzoate; NMF=N-methylformamide) and [Ca(BA)sub(2) (4-nba)sub(2) ] 2 (BA=benzamide) is reported. An unique mu 2 -eta sup(1) : eta sup(1) bridging bidentate 4-nba ligand links the hexacoordinated Ca(II) ions situated on a special position in both compounds into a one-dimensional (1-D) chain with Ca···Ca separations of 5.561 and 5.482 respectively. Each Ca(II) in the chain is bonded to a pair of symmetry related terminal amide ligands (NMF in 1; BA in 2) which are disposed trans to each other. A comparative study of several 4-nitrobenzoates of calcium is described.