The design of the structure of a coordination compound (catalyst) is of crucial importance for its catalytic applications. This paper presents a series of newly synthesized iron (III) complexes, including (benzothiazol-guanidine-Fe), (benzothiazol-imidazol-Fe), and (benzothiazol-pyrimidin-Fe), as potential catalysts for various organic reactions. To confirm their structures, the complexes were characterized using a variety of spectroscopic methods, such as FT-IR, ¹H-NMR, ¹³C-NMR, CHN elemental analysis, electronic spectra, TGA, molar conductivity, and magnetic moment. Spectroscopy and other analytical studies reveal distorted octahedral geometry in iron complexes. In order to ascertain the kinetic and thermodynamic properties of complexes, the Coats-Redfern method was used. Further research was done into these complexes' catalytic abilities for the environmentally friendly synthesis of 7-amino-4,5-dihydro-tetrazolo[1,5-a]pyrimidine-6-carbonitrile derivatives using aromatic aldehyde, malononitrile, and 5-aminotetrazole as reactants. The reactions were conducted in a compassionate environment using a green solvent. The outcomes demonstrated the excellent catalytic activity and selectivity of the complexes, which led to good yields of the intended products. As a result, the study offers useful information on the novel iron (III) complexes' synthetic uses, and the creation of effective and environmentally acceptable catalysts, and emphasizes their potential as powerful catalysts for a variety of organic transformations. This strategy's simplicity, safety, commercially accessible catalyst, stability, fast reaction time, and outstanding yields may be used in the industry in the future.