A nickel(II) complex with an unsymmetrical tetra-dentate chelating ligand derived from pyridine-2,6-dicarbaldehyde and 2-amino-thio-phenol

Abstract

[(2-{[6-(1,3-Benzo-thia-zol-2-yl)pyridin-2-yl]carbonyl-aza-nid-yl}phen-yl)sulf-anido]nickel(II), [Ni(C₁₉H₁₁N₃OS₂)], crystallizes in the centrosymmetric monoclinic space group P2₁/n with one mol-ecule in the asymmetric unit. The expected ligand, a bis-Schiff base derived from pyridine-2,6-dicarbaldehyde and 2-amino-thio-phenol, had modified in situ in a both unexpected and unsymmetrical fashion. One arm had cyclized to form a benzo[d]thia-zol-2-yl functionality, while the imine linkage of the second arm had oxidized to an amide group. The geometry about the central Ni^II atom is distorted square-planar N₃S. The mol-ecules form supra-molecular face-to-face dimers via rather strong π-π stacking inter-actions, with these dimers then linked into chains via pairwise C-H⋯O inter-actions.

Keywords: chelate ligand; crystal structure; ligand modification; nickel.