A tricobalt(II) coordination polymer incorporating in situ generated 5-methyltetrazolate ligands

A tricobalt(II) coordination polymer {Na0.5[Co3(μ4-Mtta)1.5(μ2-OAc)3(μ3-OAc)(μ3-OH)]}n (1) (Mtta = 5-methyl tetrazolate) was prepared from the solvothermal reaction of Co(OAc)2 · 4H2O with NaN3 in MeCN in the presence of water. Complex 1 was characterized by elemental analysis, IR, and X-ray crystallography. 1 consists of a unprecedented 3D hydrogen-bound supramolecular structure in which a 2D layer with unusual (326272) topology holds the adjacent layers together in a ABAB sequence via unusual O–H⋯Na pseduo–agostic interactions. Complex 1 displayed the characteristics of a weak antiferromagnetic exchange interactions between Co2+ ions in the system of Co3(Mtta)3 trigonal unit.