title: Synthesis and Straightforward Quantification Methods of Imino Nitroxide-Based Hexaradical Architecture on a Cyclotriphosphazene Scaffold.
abstract: The synthesis of a homogeneous neutral hexaradical architecture consisting of six imino nitroxide radical moieties covalently bonded on a cyclotriphosphazene scaffold was reported. The synthesis of hexaradical imino nitroxide compounds follows the Ullman procedure involving the condensation of 2,3-bis(hydroxylamino)-2,3-dimethylbutane with hexa-(4-formylphenoxy)cyclotriphosphazene (3) followed by oxidation of the condensation product hexa-[4-(1-hydroxy-4,4,5,5-tetramethyl-2-imidazoline-2-yl)phenoxy]cyclotriphosphazene (2) by NaIO4. Characterization of hexaradical was performed by X-ray and SQUID in solid state and by EPR, absorption spectroscopy, and electrochemistry in solution. CV of 1 shows an oxidation peak at 1.184 V (vs SCE) and a reduction peak at -0.883 V, both characteristics of the presence of phenyl imino nitroxide (7) moieties, suggesting that the contribution of the cyclotriphosphazene core is negligible. Attention was particularly focused on developing methods, UV-vis spectroscopy and square-wave voltammetry, to quantify the number of radicals in a way to confirm easily and rapidly the polyradicals' structure.
authors: Chemistry Department, Gebze Technical University , P.O. Box 141, Gebze 41400, Kocaeli, Turkey.
authors: Ismail
authors: I
authors: Fidan
authors: Chemistry Department, Gebze Technical University , P.O. Box 141, Gebze 41400, Kocaeli, Turkey.
authors: Emel
authors: E
authors: Önal
authors: Physics Department, Yıldız Technical University, Art and Science Faculty , Istanbul 34220, Turkey.
authors: Yusuf
authors: Y
authors: Yerli
authors: Laboratoire des Multimatériaux et Interfaces (UMR 5615), Université Claude Bernard Lyon 1 , Campus de La Doua, Villeurbanne Cedex 69622, France.
authors: Dominique
authors: D
authors: Luneau
authors: Chemistry Department, Gebze Technical University , P.O. Box 141, Gebze 41400, Kocaeli, Turkey.
authors: Vefa
authors: V
authors: Ahsen
authors: Chemistry Department, Gebze Technical University , P.O. Box 141, Gebze 41400, Kocaeli, Turkey.
authors: Catherine
authors: C
authors: Hirel