A novel 2D chiral silver(I) coordination polymer assembled from 5-sulfosalicylic acid and (2S,4R)-4-hydroxyproline: Synthesis, crystal structure, HOMO-LUMO and NBO analysis

A novel two-dimensional chiral silver(I) coordination polymer, namely {[Ag2(HSSA)(Hyp)]2·3H2O}n(1), where H3SSA = 5-sulfosalicylic acid; Hyp = (2S,4R)-4-hydroxyproline, has been synthesized under classical conditions and structurally characterized by elemental analysis, infrared spectroscopy (IR), single crystal X-ray diffraction techniques. X-ray crystallographic study revealed that complex 1 crystallizes in chiral monoclinic C2 space group with −0.02(3) Flack parameter because it consists of only one enantiomer of 4-hydroxyproline. The 2D polymeric layers of 1 are expanded into a three-dimensional supramolecular network via classical intermolecular OH⋯O, NH⋯O and OH⋯S hydrogen bonding interactions. Interestingly, complex 1 exhibits rare CH⋯Ag interaction. In addition to these interactions, non-covalent supramolecular interactions such as Ag⋯C, Ag⋯π, π⋯π stacking interactions play in important role for the formation of 3D supramolecular framework. The HOMO-LUMO and NBO analysis of 2D coordination polymer have been studied by using the density functional theory (DFT) method.