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Updated: Sep 24, 2025
Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
Pyridylbenzimidazole based Re(i)(CO)3 complexes: antimicrobial activity, spectroscopic and density functional theory
1Department of Chemistry, Faculty of Science, Cairo University Gamma Street Giza Cairo 12613 Egypt mansour@sci.cu.edu.eg inorganic_am@yahoo.com.
Abstract:
fac-[ReBr(CO)3(L1,2)] L1 = 1-ethyl-2-(pyridin-2-yl)benzimidazole (1) and L2 = 1-[(pyridin-2-yl) benzimidazole]-propyl-sulfonic acid (2), fac-[Re2Br2(CO)6L3] (3) L3 = 1,1'-(hexane-1,6-diyl)bis[2-(pyridin-2-yl)1H-benzimidazole] and fac-[ReBr(CO)3(L4,5-κ2N1N2)] (L4 = 2,6-bis(benzimidazol-2'-yl)pyridine (4) and L5 = 2,6-bis(1-ethyl-benzimidazol-2'-yl)pyridine (5) were synthesized and fully characterized using different spectrocopic and analytical tools. The spectrocopic data showed coordination of L1-3 to fac-ReBr(CO)3 via the benzimidazole and pyridine N-atoms. For 4 and 5, the absence of a two-fold axis of symmetry for L4,5 in the 1H NMR spectra reflect the κ2N1,N2 mode of coordination. The electronic properties of 1-5 were investigated by time-dependent density functional theory calculations in the singlet and triplet states. The ligands and their Re(i) complexes were assessed for their potential antimicrobial activity. Compound 5 was screened against non-malignant cell line (noncancerous human embryonic kidney cell line (HEK293)) as well as evaluated for its blood compatibility.
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