New in situ generated acylhydrazidate-coordinated complexes and acylhydrazide molecules: Synthesis, structural characterization and photoluminescence property

• In situ acylation of two ortho-position carboxylic groups with N2H4 can produce acylhydrazide molecule.
• Structural characterization of three acylhydrazidate-coordinated complexes is reported.
• Structural characterization of two acylhydrazide molecules is reported.
• Character of acylhydrazide molecule is revealed.

By utilizing the hydrothermal in situ acylation of organic acids with N2H4, three acylhydrazidate-coordinated compounds [Mn(L1)2(H2O)2] (L1 = 2,3-quinolinedicarboxylhydrazidate; HL1 = 2,3-dihydropyridazino[4,5-b] quinoline-1,4-dione) 1, [Mn2(ox)(L2)2(H2O)6]·2H2O (L2 = benzimidazolate-5,6-dicarboxylhydrazide; HL2 = 6,7-dihydro-1H-imidazo[4,5-g]phthalazine-5,8-dione; ox = oxalate) 2, and [Cd(HL3)(bpy)] (L3 = 4,5-di(3′-carboxylphenyl)phthalhydrazidate; H3L3 = 6,7-dihydro-1H-imidazo[4,5-g]phthalazine-5,8-dione; bpy = 2,2′-bipyridine) 3, as well as two acylhydrazide molecules L4 (L4 = oxepino[2,3,4-de:7,6,5-d′e′]diphthalazine-4,10(5H,9H)-dione) 4 and L5 (L5 = 4,5-dibromophthalhydrazide; L5 = 6,7-dibromo-2,3-dihydrophthalazine-1,4-dione) 5 were obtained. X-ray single-crystal diffraction analysis reveals that (i) 1 only possesses a mononuclear structure, but it self-assembles into a 2-D supramolecular network via the NhydrazineH ⋯ Nhydrazine and OwH ⋯ Ohydroxylimino interactions; (ii) 2 exhibits a dinuclear structure. Ox acts as the linker, while L2 just serves as a terminal ligand; (iii) In 3, L3 acts as a 3-connected node to propagate the 7-coordinated Cd2 + centers into a 1-D double-chain structure; (iv) 4 is a special acylhydrazide molecule. Two OH groups for the intermediates 3,3′-biphthalhydrazide further lose one water molecule to form 4; (v) 5 is a common monoacylhydrazide molecule. Via the NhydrazineH ⋯ Ohydrazine, OhydroxyliminoH ⋯ Oacylamino and the π ⋯ π interactions, it self-assembles into a 2-D supramolecular network. The photoluminescence analysis reveals that 4 emits light with the maxima at 510 nm.

By employing IR spectrum, TG curve, powder XRD pattern, X-ray single-crystal diffraction analysis, and photoluminescence analysis, structural characterization of three acylhydrazidate-coordinated complexes and two acylhydrazide molecules is revealed.Figure optionsDownload as PowerPoint slide