Two luminescent cobalt(II) coordination polymers for selective sensing of MnO4- in water

Two luminescent Co(II)-based coordination polymers (CPs) with the formulae of [Co(L1)(1,4-ndc)center dot H2O](n) (CP 1) and [Co-2(L2)(1,4-chdc)(2)](n) (CP 2) (L1 = 1,1'-(1,4-butanediyl)bis(5,6-dimethylbenzimidazole), 1,4-H(2)ndc = 1,4-naphthalenedicarboxylic acid, L2 = 1,1'-(1,4-butanediyl)bis(2-methylbenzimidazole), 1,4-H(2)chdc = 1,4-cyclohexanedioic acid) have been synthesized. Both CPs were characterized by single-crystal X-ray diffraction, thermogravimetric analysis, elemental analysis, IR spectroscopy, and powder X-ray diffraction. CP 1 reveals a 2D 3,5L2 framework, while CP 2 has a 2D (4,5)-connected 4,5L51 network. Both CPs are luminescent and can be employed for the selective detection of free MnO4- in water.