Synthesis, spectral and X-ray diffraction of two new 2D lead(II) coordination polymers formed by nicotinic acid N-oxide linkers

Abstract

Two new 2D coordination polymers, [Pb(NNO)2]n (1) and [Pb(NNO)(SCN)]n (2) (HNNO = nicotinic acid N-oxide), were synthesized and characterized by elemental analysis, FT-IR and 1H NMR spectroscopy, as well as single-crystal X-ray diffraction analysis. The thermal stability of the compounds was evaluated by thermogravimetric analysis. The compounds crystallize in the monoclinic space group P21/c. X-ray analysis of complexes revealed 2D coordination polymer containing lead atoms with PbO7 (1) and PbO4S (2) environments and hemidirected sphere. In addition to dative bonds around the lead atoms, there are Pb⋯X (X: O for 1 and N, O, S for 2) interactions to stabilize the complexes and form pseudo-capped square antiprismatic (1) and pseudo-bicapped trigonal prismatic (2) geometries. Two crystal structures are consisting of rectangular-shaped grids constructed with the NNO‾ linkers. These two-dimensional coordination polymers are further connected to form a 3D supramolecular networks by intermolecular interactions.