The syntheses of 4-[4-(4,4,5,5-tetramethyl-2-imidazoline-3-oxide-1-oxyl-2-yl)phenoxy]phthalonitrile (3, CHNO) and 4-[4-(4,4,5,5-tetramethyl-2-imidazoline-1-oxyl-2-yl)phenoxy]phthalonitrile (4) were carried out by microwave-assisted nucleophilic aromatic substitution of 4-nitrophthalonitrile (2) by the pre-formed 2-(4-hydroxyphenyl)-4,4,5,5-tetramethyl-2-imidazoline-3-oxide-1-oxyl (1). Compounds 3 and 4 were characterized unambiguously by a rich array of analyses, such as melting point, FT-IR, MALDI-TOF MS, elemental analysis, UV-Vis, CV, EPR, magnetic measurements and single-crystal X-ray diffraction. Structural studies demonstrate that the C-H...X and C-X...π (X = O and N) interactions in the radical nitronyl nitroxide groups play an important role in the assembly of the crystal structures. Moreover, cyclic voltammetry analyses show that the phthalonitrile substituent retains the redox properties of the Ullman radicals.
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http://dx.doi.org/10.1107/S2053229621001832 | DOI Listing |
Acta Biomater
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Institute of Smart Biomedical Materials, School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, PR China. Electronic address:
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Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
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State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310058, P. R. China.
Magnetic resonance imaging (MRI) is considered one of the most valuable diagnostic technologies in the 21st century. To enhance the image contrast of anatomical features, MRI contrast agents have been widely used in clinical MRI diagnosis, especially those based on gadolinium, manganese, and iron oxide. However, these metal-based MRI contrast agents show potential toxicity to patients, which urges researchers to develop novel MRI contrast agents that can replace metal-based MRI contrast agents.
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Aix Marseille Univ, CNRS, ICR UMR 7273, 13013, Marseille, France.
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December 2024
Nikolayev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences 630090 Novosibirsk Russia
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