Self-assembly of five cobalt(II) coordination polymers from 1,2-bis(1,2,4-triazol-1-yl)ethane

Abstract

Five cobalt(II) coordination polymers {[Co(bte) 2(H 2O) 2](NO 3) 2} n ( 1), {[Co(bte)(H 2O) 2(NCO) 2](H 2O) 2} n ( 2), {[Co(bte) 2(NCO) 2](H 2O)} n ( 3), [Co(bte) 2(NCS) 2] n ( 4) and {[Co(bte)(H 2O) 2(NCS) 2][Co(bte) 2(NCS) 2]} n ( 5) (bte = 1,2-bis(1,2,4-triazol-1-yl)ethane) have been synthesized and characterized by elementary analyses, IR, thermogravimetric analyses and X-ray diffraction analyses. There are three motifs (2D (4,4) network, single chain and double-stranded chain) in five complexes: 2D (4,4) network ( 1), single chain ( 2), double-stranded chain ( 3 and 4), and a combination of two motifs (single chain + double-stranded chain) ( 5). A conformational analysis of the ligand molecule demonstrates that the flexibility of bte and the rotational freedom of the triazole rings result in the diversity of the topologies of the complexes.