Synthesis, spectroscopic characterisation, corrosion inhibition studies and dyeing properties of lanthanide(III) complexes of 1-[(3-carboxyethyl-4,5-dimethylthiophen-2-yl)azo]-2-naphthol

Ligational behaviour of the heterocyclic ligand obtained by coupling of diazotized 2-amino-3-carboxyethyl-4,5-dimethylthiophene with beta-naphthol towards some selected lanthanide(III) ions has been studied. Various spectral and physico-chemical techniques have been used to confirm the coordination sites of the ligand (HTAN) and its lanthanide(III) complexes. It has been observed that these ligands coordinate to the metal ions in a neutral tridentate fashion. Thermal stability of metal chelates and structural stability of the chelating agent has been studied by thermal analysis. As lanthanides and azo dyes are reported as good corrosion inhibitors we have examined the corrosion inhibition activities of HTAN and its metal complexes. Also dyeing properties of the azo dye and some of its selected complexes towards cotton fabrics has been evaluated, as the traditional application field of the synthetic azo dyes still remains in the textile industry.

Automated summary

The ligational behavior of a heterocyclic ligand obtained by coupling specific chemicals was studied in coordination with selected lanthanide(III) ions. The ligands were found to coordinate in a neutral tridentate fashion to metal ions, showing good thermal and structural stability. Additionally, the corrosion inhibition and dyeing properties of the ligand and its metal complexes were evaluated, highlighting potential applications in industries such as textiles.