Hydrogen bonds dependent assembly of two novel 1D complexes constructed by bis(4-pyridinecarboxamide)alkanes-N,N′-dioxide

Two novel complexes of CoL1(SCN)2(H2O)24H2O (1) and CoL2(SCN)2(H2O)22H2O (2) (L1 = bis(4-pyridinecarboxamide)-1,2-ethane-N,N′-dioxide and L2 = bis(4-pyridinecarboxamide-1,6-hexane)-N,N′-dioxide) constructed by pre-designed ligands of bis(4-pyridinecarboxamide)alkanes-N,N′-dioxide have been synthesized and structurally characterized. Both compounds contain similar 1D chains bridged by the ligands. However, the chains in 1 and 2 are connected by different interchain hydrogen bonds to form different 2D layers, which depend on the flexibility and length of the ligands. Furthermore, the thermal stability of 1 and 2 were studied by using thermogravimetric analysis and temperature dependent powder X-ray diffraction method.

Graphical abstractTwo novel complexes constructed by pre-designed ligands of bis(4-pyridinecarboxamide)alkanes-N,N'-dioxide have been synthesized and structurally characterized. Both compounds contain similar 1D chains bridged by the ligands. However, the chains are connected by different interchain hydrogen bonds to form different 2D layer, which depend on the flexibility and length of the ligands.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Two novel pyridine N-oxide ligands with carboxamide group were firstly used. ► The addition of carboxamide group can enhance coordination flexibility of ligands. ► 1 and 2 are a suitable system to explore weak force on the supramolecular assembly.