Structural investigation of one- and two-dimensional coordination polymers based on cobalt-bis(dioxolene) units and 1-hydroxy-1,2,4,5-tetrakis(pyridin-4-yl)cyclohexane.

The combination of cobalt, 3,5-di-tert-butyldioxolene (3,5-dbdiox) and 1-hydroxy-1,2,4,5-tetrakis(pyridin-4-yl)cyclohexane (tpch) yields two coordination polymers with different connectivities, i.e. a one-dimensional zigzag chain and a two-dimensional sheet. Poly[[bis(3,5-di-tert-butylbenzene-1,2-diolato)bis(1,5-di-tert-butyl-4-oxocyclohexa-2,5-dien-1-yl-3-olato)[μ4 -1-hydroxy-1,2,4,5-tetrakis(pyridin-4-yl)cyclohexane]cobalt(III)]-ethanol-water 1/7/5], {[Co2 (C14 H20 O2 )4 (C26 H24 N4 O)]·7C2 H5 OH·5H2 O}n or {[Co2 (3,5-dbdiox)4 (tpch)}·7EtOH·5H2 O}n , is the second structurally characterized example of a two-dimensional coordination polymer based on linked {Co(3,5-dbdiox)2 } units. Variable-temperature single-crystal X-ray diffraction studies suggest that catena-poly[[[(3,5-di-tert-butylbenzene-1,2-diolato)(1,5-di-tert-butyl-4-oxocyclohexa-2,5-dien-1-yl-3-olato)cobalt(III)]-μ-1-hydroxy-1,2,4,5-tetrakis(pyridin-4-yl)cyclohexane]-ethanol-water (1/1/5)], {[Co(C14 H20 O2 )2 (C26 H24 N4 O)]·C2 H5 OH·5H2 O}n or {[Co(3,5-dbdiox)2 (tpch)]·EtOH·5H2 O}n , undergoes a temperature-induced valence tautomeric interconversion.