Monoclinic and orthorhombic polymorphs of 4,4′,6,6′-tetrachloro-2,2′-(piperazine-1,4-diyldimethylene)diphenol
作者:Koji Kubono、Kunihiko Yokoi
DOI:10.1107/s0108270107035408
日期:2007.9.15
The title compound, C18H18Cl4N2O2, crystallizes as monoclinic and orthorhombic polymorphs from CHCl3-CH3OH solution. In both polymorphic forms, the molecule lies on a crystallographic centre of inversion (at the piperazine ring centroid) and exhibits an intramolecular O-H center dot center dot center dot N hydrogen bond. In the monoclinic polymorph (space group P2(1)/ c), the molecules are linked by intermolecular C-H center dot center dot center dot Cl hydrogen bonds into a ribbon sheet built from R-8(8)(34) rings. In the orthorhombic polymorph (space group Pbcn), the molecules are linked by intermolecular C-H center dot center dot center dot O hydrogen bonds into a ribbon sheet of R-6(6)(34) rings. The sheets in the orthorhombic polymorph are crosslinked into a three-dimensional framework by pi-pi stacking interactions.
Synthesis, structure, Hirshfeld surface analysis and catecholase activity of Ni(II) complex with sterically constrained phenol based ligand
Abstract A mononuclear square planarNi(II) complex [NiIIL] (1) with sterically encumbered phenol based tetra dentate N2O2 ligand has been synthesized. Several spectroscopic tools have been employed to characterize this complex. The crystal structure of this Ni(II) complex obtained from single crystal X-ray diffraction study reveals that the central metal ion adopts a square planar environment and crystalized