摘要：

New chelating radical ligands pzNNH, pzINH, and pzbisINH (3-pyrazolyl nitronyl nitroxide, 3-pyrazolyl imino nitroxide, and pyrazole-3,5-diyl bis(imino nitroxide), respectively) were prepared. Complexation of these ligands with Ag⁺ gave [Ag(pzNN)]_n, [Ag(pzIN)]₆, and [Ag(pzbisIN)]_n containing the corresponding anionic forms of the ligands. From the X-ray crystal structure analysis, [Ag(pzIN)]₆ was characterized as a dimer of almost planar triangular moieties where the pyrazolate worked as a bridge, and metal–metal bonds brought about dimerization of triangles. [Ag(pzbisIN)]_n was characterized as a uniform zigzag chain consisting of pyrazolate bridges and Ag ions with a cis-N_pz–Ag–N_pz coordination structure. Antiferromagnetic interactions observed could be analyzed based on the structures determined for both compounds. Ferromagnetic coupling was observed in [Ag(pzNN)]_n, and a polymeric structure was assumed although the crystal structure could not be determined. Novel supramolecular architectures using pyrazolate-substituted imino nitroxides have been developed, using the unique coordinative versatility of the pyrazolate derivatives.

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