Two New Cd(II) and Co(II) Coordination Polymers Based on a 1,10-Phenanthroline Derivative and Tri- or Tetra-Carboxylates: Syntheses, Structures and Photoluminescence

Two new coordination polymers constructed with the 1,10-phenanthroline derivative 2-(2-chloro-6-fluorophenyl)-1H-imidazo[4,5-f][1,10]-phenanthroline (L) and different carboxylates, namely, [Cd₂(L)₂(1,3,5-BTC)(Cl)]·H₂O (1) and [Co₂(L)₂(1,2,4,5-BTC)(H₂O)₂] (2), have been synthesized under hydrothermal conditions (1,3,5-BTC = 1,3,5-benzenetricarboxylate anion and 1,2,4,5-BTC = 1,2,4,5-benzenetetracarboxylate anion). Crystal data for 1: C₄₇H₂₅Cd₂Cl₃F₂N₈O₇, triclinic, space group P1̅, a = 10.1084(5), b = 14.9285(7), c = 15.2930(4) Å, α = 72.1050(10), β = 86.160(2), γ =79.6000(10)°, V = 2159.88(16) Å³, Z = 2. Crystal data for 2: C₂₄H₁₃ClCoFN₄O₅, triclinic, space group P1̅, a = 7.4767(15), b = 10.094(2), c = 14.772(3) Å, α = 91.23(3), β = 100.95(3), γ =106.57(3)°, V = 1045.8(4) Å³, Z = 2. Their crystal structures have been determined by single-crystal X-ray diffraction analyses, and the compounds further characterized by physico-chemical and spectroscopic methods. In 1, each 1,3,5-BTC anion connects five Cd(II) atoms to form a double chain. These chains are extended into 2D supramolecular networks through π − π interactions. N–H ··· Cl, N–H ··· O and O–H ··· N hydrogen bonding interactions further stabilize the network of 1. In 2, each 1,2,4,5-BTC anion bridges four Co(II) atoms to yield a chain. π − π interactions among adjacent chains result in a 2D supramolecular architecture.