A novel “sawtooth-like” heterometallic Sr-Mo 18-metallacrown-6 complex: Synthesis, structure and anticancer activity

Dou, Mingyu; Yang, Hua; Zhao, Xiaojuan; Zhang, Zhen; Li, Dacheng; Dou, Jianmin

doi:10.1016/j.inoche.2020.108127

Cited by 1 publication

(1 citation statement)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The organic molecule N ,2-dihydroxybenzamide (H 2 dihybe) ( Scheme 1 A) incorporates a hydroxamate group in addition to the phenoxy group in the ortho-position and exhibits a rich coordination chemistry with many transition metals [ 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 ] with potential applications in various fields ranging from medicine [ 41 , 42 , 43 ] to materials [ 44 ], and physical sciences [ 40 , 45 ].…”

Section: Introductionmentioning

confidence: 99%

Synthesis, Structural and Physicochemical Characterization of a Titanium(IV) Compound with the Hydroxamate Ligand N,2-Dihydroxybenzamide

et al. 2021

View full text Add to dashboard Cite

The siderophore organic ligand N,2-dihydroxybenzamide (H2dihybe) incorporates the hydroxamate group, in addition to the phenoxy group in the ortho-position and reveals a very rich coordination chemistry with potential applications in medicine, materials, and physical sciences. The reaction of H2dihybe with TiCl4 in methyl alcohol and KOH yielded the tetranuclear titanium oxo-cluster (TOC) [TiIV4(μ-O)2(HOCH3)4(μ-Hdihybe)4(Hdihybe)4]Cl4∙10H2O∙12CH3OH (1). The titanium compound was characterized by single-crystal X-ray structure analysis, ESI-MS, 13C, and 1H NMR spectroscopy, solid-state and solution UV–Vis, IR vibrational, and luminescence spectroscopies and molecular orbital calculations. The inorganic core Ti4(μ-O)2 of 1 constitutes a rare structural motif for discrete TiIV4 oxo-clusters. High-resolution ESI-MS studies of 1 in methyl alcohol revealed the presence of isotopic distribution patterns which can be attributed to the tetranuclear clusters containing the inorganic core {Ti4(μ-O)2}. Solid-state IR spectroscopy of 1 showed the presence of an intense band at ~800 cm−1 which is absent in the spectrum of the H2dihybe and was attributed to the high-energy ν(Ti2–μ-O) stretching mode. The ν(C=O) in 1 is red-shifted by ~10 cm−1, while the ν(N-O) is blue-shifted by ~20 cm−1 in comparison to H2dihybe. Density Functional Theory (DFT) calculations reveal that in the experimental and theoretically predicted IR absorbance spectra of the ligand and Ti-complex, the main bands observed in the experimental spectra are also present in the calculated spectra supporting the proposed structural model. 1H and 13C NMR solution (CD3OD) studies of 1 reveal that it retains its integrity in CD3OD. The observed NMR changes upon addition of base to a CD3OD solution of 1, are due to an acid–base equilibrium and not a change in the TiIV coordination environment while the decrease in the complex’s lability is due to the improved electron-donating properties which arise from the ligand deprotonation. Luminescence spectroscopic studies of 1 in solution reveal a dual narrow luminescence at different excitation wavelengths. The TOC 1 exhibits a band-gap of 1.98 eV which renders it a promising candidate for photocatalytic investigations.

show abstract