A Molecular Helix: Self-Assembly of Coordination Polymers from d¹⁰ Metal Ions and 1,10-Phenanthroline-5,6-dione (pdon) with the Bridges of SCN⁻ and Cl⁻ Anions

Abstract

Novel complexes of (half)-filled d-configurations, including [Zn(pdon)(SCN)(μ-Cl)(H 2 O)] n (1), [Cd 2 (pdon) 2 -(μ 1,3 -SCN) 4 ] n (2), [Hg(pdon) 2 Cl 2 ] (3), and [Mn(pdon) 2 (SCN) 2 ] (4) (pdon = 1,10-phenanthroline-5,6-dione), were synthesized and structurally characterized by single crystal X-ray diffraction. Self-assembly behaviors of these metal ions with anions are essentially different, although some of them are elements of the same group. Various supramolecular interactions of H-bonding, π 3 3 3 π stacking, and C-X 3 3 3 π (X=H, O, and S) are observed in the structures. In 1, central Zn 2þ cations are connected to form an infinite one-dimensional (1D) zigzag chain by bridged Cland further extended to two-dimensional layers via weak interactions. Complex 2 consists of dinuclear units doubly bridged by two end-to-end (EE) SCNanions and linked to 1D molecular helix along the b-axis with a long pitch of 13.077 A ˚. The helix displays racemic mixtures in the crystal. Complexes 3 and 4 are six-coordinated with distorted octahedron geometry. pdon serves as a terminal ligand in complexes. Spectroscopic and electrochemical properties of pdon and the complexes are studied in dimethyl sulfoxide (DMSO) solution at room temperature. Circular dichroism (CD) spectral results suggest that there is phenomenon of spontaneous resolution in the DMSO solution for the spiral structure 2.

Self-assembly, crystal structure, and spectroscopy properties of two new complexes with 1,10-phenanthroline-5,6-dione and SCN ligands

“…It is noted that two crystal structures exhibit dif ferent coordination forms comparable to the our reported similar complexes [14]. Herein, we report the synthesis, crystal structure and spectroscopy proper ties of complexes I and II.…”

Synthesis and Characterization of New 2D Coordination Polymers based on Mn(NCS)2 and Ni(NCS)2 with 1, 2‐Bis(4‐pyridyl)‐ethane as Co‐Ligand

“…In this context it is noted that for chalcophilic metals like e.g. cadmium the situation is opposite in order that this cations prefer a μ‐1, 3‐bridging coordination 37–42…”

Crystal structure of catena-[(μ2-5-methylisophthalato)(μ2-1,3-bis-(1,2,4- triazol-1-yl)pro pane)]zinc(II)dihydrate, [Zn(C9H6O4)(C7H10N6)]·2H2O, C16H20N6O6Zn

“…Photoluminescent properties of coordination compounds which contain d 10 metal centers have been attracting increasing interest [1][2][3][4][5][6][7]. Major reasons for this interest stem from the d 10 metal ions not only possessing various coordination numbers and geometries, but also exhibiting photoluminescent properties when bound to functional ligands.…”