Three new organotin(IV) complexes, [Me₃Sn(H₂L)]₂ (1), Bu₃Sn(H₂L) (2), and [(Bu₂Sn(H₂L))₂O]₂ (3) were synthesized by the reaction of 2-[4-hydroxy-3-((2-hydroxyethylimino)methyl)phenylazo]benzoic acid (H₃L) with appropriate alkyltin(IV) precursors. The complexes were characterized by elemental analysis, IR, and multinuclear (¹H, ¹³C and ¹¹⁹Sn) NMR spectroscopy. Further, the complex 1 was analyzed by single-crystal X-ray analysis. It displays a 24-membered cyclic dimeric Me₃Sn^IV(H₂L) unit where the ligand act as a bridging framework using its carboxylate-O and phenoxy-O atoms. The Sn(IV) adopts distorted trigonal-bipyramidal geometry. In the solution state, the structures were determined by ¹¹⁹Sn-NMR spectroscopy, and the complexes 1 and 2 have distorted tetrahedral geometry, whereas complex 3 shows distorted trigonal-bipyramidal geometry around the tin centres. The Hirshfeld surface analysis and DFT calculations, together with a topological analysis of the electron density distribution in the crystal structure of complex 1, indicate that its molecular packing determined by various noncovalent interactions, including stacking and hydrogen bonding. The antibacterial studies of the ligand and the complexes (1–3) against gram-negative bacteria viz. Klebsiella pneumoniae (A),Vibrio cholerae (M) and Shigella boydii (Q) and gram-positive bacteria viz.Staphylococcus aureus (J), Streptococcus pneumonia (K) are promising and the compounds can be treated as potential common antibacterial materials.

The objective of this study was to utilize paper chromatography (PC) as a cost-effective and accessible method to impart fundamental principles of chromatography to undergraduate students in introductory inorganic chemistry courses. The experiments focused on detecting and separating metal ions from various groups in the analytical table. Specifically, the study aimed to educate students on the separation and identification of metal ions, comparing color spots and retention factor values, and understanding the influence of alkalinity during metal ion oxidation. Paper chromatography and planar chromatography share the use of solid, flat stationary phases. In this study, Whatman quantitative grade 41 filter paper was employed as the stationary phase. Minimal sample quantities were utilized for qualitative analysis. Through the use of different eluting agents, PC was employed to separate and identify transition metal ions such as (Fe3+ & Cr3+) in group III, (Pb2+ & Cu2+) in group II, Co2+ & Ni2+ in group IV, (Co2+ & Cu2+) in group IV and II, (Cu2+ & Fe3+) in group II and III, and (Mo6+ & W6+) in group VI, based on their distinct color spots and retention factor (Rf) values. This qualitative investigation enabled undergraduate students to appreciate the efficacy of PC in identifying and separating pairs of metal ions through observation of different color spots and their corresponding Rf values.