Spectroscopic and structural studies of the 2D Mn(II) coordination polymer from a bridging Noxa, Npy bidentate ligand; tetra-n-butylammonium[5-(3-pyridyl)-1,3,4-oxadiazole-2-thiolate]

A coordination polymer {[Mn(3-pyt)2(H2O)2][N(n-Bu)4]+[3-pyt]−}n (3) has been synthesized from the reaction of tetra-n-butylammonium[5-(3-pyridyl)-1,3,4-oxadiazole-2-thiolate] {[N(n-Bu)4]+[3-pyt]−} and Mn(OAc)2 · 4H2O. The ligand and the Mn(II) complex 3 have been characterized by elemental analyses, IR, 1H and 13C NMR spectroscopy, in addition 3 has also been studied crystallographically. The single crystal X-ray structure of the 3 shows that the ligand is bonded to Mn(II) via its pyridyl and oxadiazole nitrogen atoms. This bonding pattern connects the Mn(II) centres to afford an uniform two dimensional coordination frame work where the [Mn(3-pyt)2(H2O)2]n molecules are stacked in a parallel layers. The overall arrangement of molecules in crystal lattice results in open channels in which the enclosed tetra-n-butylammonium cations are stabilized by anionic oxadiazole molecules through N+···S− ionic interactions.

The newly synthesized ligand tetra-n-butylammonium{5-(3-pyridyl)-1,3,4-oxadiazole-2-thiolate {[N(n-Bu)4]+[3-pyt]−} bonds to Mn(II) via Npy, Noxa. in a bidentate bridging mode and generates a coordination polymer {[Mn(3-pyt)2(H2O)2][N(n-Bu)4]+[3-pyt]−}n. The specific arrangement of molecules along b axis, afforded two dimensional metal–organic framework which stacked the molecules in parallel layered manner resulting in a supramolecular architecture.Figure optionsDownload as PowerPoint slide