<p>In the present work, Silsesquioxane containing 2-aminopyrimidine (Si2am2py), a hybrid material, was obtained by sol-gel method and organofunctionalized by SN2 reaction with 2-aminopyrimidine (2am2py) organic ligands. The FTIR, ¹³C and ²⁹Si solid-NMR, 1H, and ¹³C liquid-NMR techniques featured the Si2am2py and the product after hydrolyzing siloxane bonds in NaOD/D2O and XRD to confirm their structures. These techniques showed a connection between the –α carbon of the propyl group and the nitrogen of the amine group present in the 2am2py, which conferred adsorption sites for the structure. This material, Si2am2py, was applied to the adsorption of Cu²⁺ ions. The adsorption results showed the viability of using Si2am2py as an adsorbent material. The adsorption isotherms of Cu²⁺ ions followed the Freundlich model, indicating heterogeneous and multilayer adsorption. The Si2am2py material adsorbs 1.21 mmol Cu²⁺ per gram of material.</p> Graphical Abstract <p></p>