Synthesis and crystal structure of a two-dimensional Co coordination polymer: poly[(μ-3-carb-oxy-benzoato)[μ-5-(pyridin-4-yl)-1,2'-3,3'-bi[1,2,4-triazole]]cobalt(II)].

In the title compound, [Co(CHO)(CHN)] , the divalent Co atom is six-coordinated to three N atoms from two symmetrical 5-(pyridin-4-yl)-1,2'-3,3'-bi[1,2,4-triazole] (Hpyttz) ligands and three O atoms from three symmetrical 3-carb-oxy-benzoate (Hbdic) ligands, leading to a distorted {CoNO} octa-hedral coordination environment. Two Co cations are linked by four bridging carboxyl-ate groups to generate a dinuclear [Co(CO)] unit. The dinuclear units are further connected into a chain along [010] the Hbdic ligands. The other infinite chain, along [100], is formed through the Hpyttz ligands. Finally, the two kinds of chains are cross-linked, by sharing the Co cations, into a two-dimensional network. In the crystal, adjacent layers are further linked by O-H⋯N hydrogen bonds into a three-dimensional framework.