New Manganese(II) Coordination Compounds with 4-((1H-Pyrrol-2-yl)methylene-amino)-4H-1,2,4-triazole

Russian Journal of Coordination Chemistry/Koordinatsionnaya Khimiya. 2025. Vol. 51. No. 6. P. 472–487.

Bovkunova A., Bazhina E., Shmelev M., Gogoleva N., A.A. Anisimov, Котцов С. Ю., Бабешкин К. А., N.N. Efimov, Metlin M., I.V. Taydakov, Фетисов Л. Н., Святогорова А. Е., Зубенко А. А., Кискин М. А., Eremenko I.

The reaction of manganese(II) chloride with the azomethine ligand 4-((1H-pyrrol-2-yl)methylene-amino)-4H-1,2,4-triazole (HPyrtrz) affords crystals of 1D polymeric compound [MnII(HPyrtrz)(H2 O)Cl2]n (I). The addition of the coligand 1,10-phenanthroline (Phen) to the synthesis of compound I results in the sequential crystallization of two products: 1D polymeric compound [MnII(Phen)Cl2]n (II) and mononuclear complex [MnII(Phen)2Cl2]·HPyrtrz (III). Complex III is isolated as the single product in the reaction of compound I with Phen or in the reaction of the known complex [MnII(Phen)2Cl2] with HPyrtrz, respectively. The crystal structures of compounds I–III are determined by single-crystal X-ray diffraction (XRD) (CIF files CCDC nos. 2339139 (I), 2344064 (II), and 2339140 (III)). The antimicrobial properties toward bacterial strains E. coli and S. aureus and mold fungus Penicillium italicum Wehmer are studied for compounds I and III. The measurements of the temperature dependence of the magnetic susceptibility show antiferromagnetic exchange interactions between the Mn2+ ions (J = –2.69 cm–1) in compound I. The spectral luminescence studies show that HPyrtrz, I, and III exhibit blue luminescence in the solid phase.

Keywords: x-ray diffraction, Magnetic properties, luminescence, Schiff bases, antimicrobial activity, manganese(II) complexes, 4-amino-4H-1,2,4-triazole derivatives