Metal(II)-organic coordination polymers with two distinct atropisomeric building units from an axially prochiral inner salt through interchain C-H•••X hydrogen bonds (X = O, Cl; metal = cobalt, nickel)

Two isostructural photoluminescent metal-organic coordination polymers, namely, [M(H-mpypdc)(Cl)(H2O)(3)](n) (mpypdc = 2,6-dimethyl-4-(pyridin-4-yl)pyridine-3,5-dicarboxylate; M = Co (2) and Ni (3)), were synthesized from H(2)mpypdc (1), and characterized by single crystal X-ray analyses. New ligand 1 is an inner salt. In the metal-organic coordination polymeric chains, two distinct S- and R-atropisomeric units are generated from the axially prochiral 1 through C-H center dot center dot center dot X (X = O, Cl) hydrogen bonds. There have interesting 2D supramolecular networks [M(Cl)(H2O)(2)](n), in the crystal structures of title compounds. The photoluminescence of new compounds are also investigated in solid state at ambient temperature. (c) 2007 Elsevier B.V. All rights reserved.