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  • A Series of Zinc Mononuclear Complexes with Imidoyl Amidine Ligands: Syntheses, Crystal Structures, and Photoluminescence Properties
Title: A Series of Zinc Mononuclear Complexes with Imidoyl Amidine Ligands: Syntheses, Crystal Structures, and Photoluminescence Properties
Three amidine-based ligands were used in the crystal design of a series of mononuclear Zn(II) complexes. Interaction of zinc chloride, ZnCl2, with N-2-pyridylimidoyl-2-pyridylamidine (Py2ImAm) resulted in complexes [Zn(Py2ImAm)2] (1) and [ZnCl2(Py2ImAm)] (2). In [Zn(Py2ImAm)2] (1, monoclinic, P21/c), the metal ion was coordinated with the bidentate pocket of the anionic form of Py2ImAm, while in [ZnCl2(Py2ImAm)] (2, monoclinic, P21/n), the tridentate coordination to a neutral Py2ImAm was completed by two chloride anions. This structural variation was achieved by a pH-controlling strategy using the weak base triethylamine (TEA). Otherwise, three ionic complexes were obtained with 2-amidinopyridine (PyAm) and Zinc(II), [ZnCl(PyAm)2]Cl (3, triclinic, P-1), [ZnCl(PyAm)2]2[ZnCl4]·C2H5OH (4, monoclinic, P21/n), and [ZnCl(PyAm)2]2Cl·CH3OH (5, triclinic, P-1). They comprised the same [ZnCl(PyAm)2]+ monocation with a butterfly-like shape provided by the bidentate chelate coordination of two PyAm neutral entities and a chloride ligand. In a similar butterfly shape, ionic complex [ZnCl(PmAm)2]2[ZnCl4] (6, monoclinic, C2/c) comprised the mononuclear [ZnCl(PmAm)2]+ cations with two bidentate chelate-coordinated 2-amidinopyrimidine (PmAm) as neutral ligands. The Zn(II) pentacoordinated arrangement in 3–6 was variable, from square pyramidal to trigonal bipyramidal. The reported compounds’ synthetic protocols, crystal structures and photoluminescence properties are discussed.  more » « less
Award ID(s):
2122108
PAR ID:
10589557
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
MDPI
Date Published:
Journal Name:
Chemistry
Volume:
6
Issue:
4
ISSN:
2624-8549
Page Range / eLocation ID:
760 to 772
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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