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Nitroxide radicals appended to phthalonitriles: synthesis, structural characterization and photophysical properties
Author(s) -
Fidan Ismail,
Onal Emel,
Hirel Catherine
Publication year - 2021
Publication title -
acta crystallographica section c
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.304
H-Index - 17
ISSN - 2053-2296
DOI - 10.1107/s2053229621001832
Subject(s) - phthalonitrile , nitroxide mediated radical polymerization , electron paramagnetic resonance , chemistry , radical , cyclic voltammetry , nucleophilic aromatic substitution , nucleophilic substitution , substituent , crystal structure , photochemistry , polymer chemistry , crystallography , organic chemistry , electrochemistry , phthalocyanine , polymer , monomer , nuclear magnetic resonance , physics , radical polymerization , electrode
The syntheses of 4‐[4‐(4,4,5,5‐tetramethyl‐2‐imidazoline‐3‐oxide‐1‐oxyl‐2‐yl)phenoxy]phthalonitrile ( 3 , C 21 H 19 N 4 O 3 ) 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.