Effect of Organic Dicarboxylates with Different Rigidity on the Construction of Cobalt(II) Complexes with a Semi‐rigid Tripyridyl‐bis‐amide Ligand

Abstract

Three coordination compounds with dimensions from 0D to 2D, namely, [Co(bppdca)2(HL1)2] (1) [Co(bppdca)(L2)(H2O)]·2H2O (2) and [Co(bppdca)(L3)]·3H2O (3) [bppdca = N,N′‐bis(pyridine‐3‐yl)pyridine‐2,6‐dicarboxamide, H2L1 = 2,5‐pyridinedicarboxylic acid, H2L2 = 4,4′‐oxybisbenzoic acid, H2L3 = 2‐carboxymethylsulfanyl nicotinic acid] were hydrothermally synthesized and structurally characterized. Single crystal X‐ray diffraction analysis reveals that complex 1 is a discrete 0D complex, in which the bppdca ligand and the H2L1 act as the terminal groups to coordinate with the CoII ions. In coordination polymer 2, two bppdca ligands coordinate in anti configuration with two CoII ions to generate a 28‐membered Co2(bppdca)2 loop, which is further extended into 1D ladder‐like double chain by pairs of L2 ligands. In 3, the CoII ions are linked by bppdca ligands to generate 1D wave‐like chain, which is further connected by the L3 to form a 2D network. Finally, the coordination compounds 1–3 are extended into 3D supramolecular frameworks through the hydrogen bonding interactions. The CoII ions and the bppdca ligands in the title coordination compounds exhibit different coordination characters and conformations. The effect of organic dicarboxylates with different rigidity and length on the structures of CoII coordination compounds was investigated. In addition, the fluorescence and electrochemical behaviors of coordination compounds 1–3 were reported.

Structural Influencing Factors on ZnII/CdII Coordination Polymers Based on Tri‐pyridyl‐bis‐amide: Assembly, Structures, Fluorescent Sensing and Selective Photocatalysis

“…The 1D channel‐like chains are further extended by two types of hydrogen bonding interactions between the lattice water molecules and oxygen atoms of oba anions [O1W–H1WA ··· N2(C), O ··· O 3.11 Å; O1W–H1WB ··· O5, O ··· O 2.90 Å], forming a 2D supramolecular sheet (Figure S4b). Our group has reported a Co II complex based on L1 ligand and oba anion {[Co(bppdca)(L2)(H 2 O)] · 2H 2 O (bppdca = L1, L2 = oba)} 15. The structure is similar to that of 3 except for different size of the loop.…”