TITLE:
Synthesis and Crystal Structures of Two Metal-Radical Complexes
AUTHORS:
Youjuan Zhang, Caiwen Zhang, Jing Chen
KEYWORDS:
M(II)-Radical Complex, Quinoxalinyl-Substituted Imino Nitroxide, Synthesized, Characterized
JOURNAL NAME:
Open Journal of Inorganic Chemistry,
Vol.11 No.3,
July
14,
2021
ABSTRACT: Two new M(II)-radical complexes [M(hfac)2(IM-o-QN)] (M = Ni(1), Zn(2); IM-o-QN = 4'-quinoxalinyl-substituted imino nitroxide; hfac = hexafluoroa-cetylacetonate) have been synthesized and characterized by X-ray diffraction analysis, element analyses, IR and UV-Visible spectroscopy. X-ray analysis reveal that the structures of both complexes are similar configuration and differently spatial symmetries. The complex 1 crystallizes in the triclinic Pī space group with the respective cell parameters: a = 9.1189(18)Å, b = 9.836(2) Å, c = 18.537(4) Å, α = 75.92(3)°, β= 81.95(3)°, γ = 69.32(3)°, V = 1506.1(5) , Z = 2, whereas the complex 2 is in monoclinic C2/c space group with the respective cell parameters: a = 26.996(5) Å, b = 9.5223(19) Å, c = 23.961(5) Å, α = 90.00°, β= 91.07(3)°, γ= 90.00°, V = 6158(2) , Z = 8. In two new M(II)-radical complexes, the central M(II)(Ni(1) and Zn(2)) ions are coordinated by four oxygen atoms from two hfac and two nitrogen atoms from imino nitroxide radicals to form a distorted octahedron. Additionally, the optical properties and thermal analysis of the two complexes are reported.