Synthesis and characterization of Mn(II) and Fe(III) complexes with the condensation product of thiosemicarbazide and 2-acetylthiazole

Abstract

The HL ligand, (E)-2-(1-(thiazol-2-yl)ethylidene)hydrazine-1-carbothioamide, was obtained from the condensation reaction of thiosemicarbazide and 2-acetylthiazole in water. The reaction of the HL ligand with the metal salt MnCl2·4H2O in a molar ratio 1:1 in methanol/water mixture results in the formation of bis Mn(II) complex with composition [MnL2]. Complex 1 crystallizes in the triclinic crystal system with space group P−1. The Mn(II) ion is hexacoordinated with two tridentate ligands L through NNS sets of donor atoms. The geometry around the Mn is described as a distorted trigonal prism (Fig. 1). The reaction of the ligand HL with Fe(BF4)2·6H2O in a molar ratio 1:1 in methanol results in the formation of bis Fe(III) complex with composition [Fe(L)2]BF4·H2O. The Fe(III) ion with L form six-coordinate complex in which two deprotonated ligand molecules coordinate in a mer arrangement, forming a distorted octahedral complex by chelation through NNS sets of donor atoms (Fig. 1). Complex 2 crystallizes in the orthorhombic crystal system with space group Pbca.