New pyridine-monoacylhydrazidate-coordinated transition-metal complexes

摘要

By applying the hydrothermal in situ acylation reactions between alkyl-substituted pyridine-2,3-dicarboxylic acids and hydrazine hydrate, six pyridine-monoacylhydrazidate-coordinated transition-metal complexes [Mn(MPDH)_2] 1, [M(MPDH)_2(H_2O) _2]·2H_2O (M~(2+) = Co~(2+) 2, Zn~(2+) 3), [Mn(EPDH)_2(H_2O)_2] 4 and [M(EPDH)_2(H_2O)_2] (M~(2+) = Zn ~(2+) 5, Co~(2+) 6) (MPDH = 6-methylpyridine-2,3- dicarboxylhydrazidate; EPDH = 5-ethylpyridine-2,3-dicarboxylhydrazidate) were obtained. Although only compound 1 is a 1-D chained coordination polymer and the others are the mononuclear molecular entities, they all further self-assemble into the interesting supramolecular networks via hydrogen-bonded interactions between pyridine-monoacylhydrazidate ligands. Two Zn~(2+) compounds 3 and 5 possess the fluorescence properties with maximum emissions at 517 nm for 3 and 530 nm for 5 upon excitation, respectively. The magnetic analysis for compound 1 indicates there exists the antiferromagnetic interactions between the Mn(II) ions.