New bis-di-organotin compounds derived from aminoacid-imine-hexadentate ligands. Multifunctional evaluation as corrosion inhibitors, antibacterials and asphaltene dispersants/inhibitors

• Published in: Polyhedron 2013-03, Vol.52, p.301-307
• Main Authors: Hernández-Altamirano, Raúl, Mena-Cervantes, Violeta Y., Chávez-Miyauchi, Tomás Eduardo, Nieto-Álvarez, David Aarón, Domínguez-Aguilar, Marco A., Zamudio-Rivera, Luis S., Barba, Victor, Fernández-Perrino, Francisco José, Pérez-Miranda, Sandra, Beltrán, Hiram I.
• Format: Article
• Language: English
• Subjects: Aminoacid; Antibacterial agents; Asphaltenes stabilization; Corrosion inhibitors; Organotin
• ISSN: 0277-5387
• DOI: 10.1016/j.poly.2012.09.022

A new class of bis-di-organotin (IV) compounds were synthesized in good yields (ca. 80%) by a one-step five molecules reaction in which intervene two molecular equivalents of leucine, one of 5,5′-methylene-bis-salicylaldehyde and either two of di-n-butyltin (IV) or diphenyltin (IV) oxides, that independently provided two bis-di-organotin derivatives. The structures of these two compounds were established by 1H, 13C and 119Sn NMR, as well as by IR and elemental analysis. In both cases the 119Sn chemical shifts are characteristic of pentacoordinated atoms in solution of non-coordinating solvent (CDCl3). Once characterized, the novel compounds were tested as corrosion inhibitors at 25, 50 and 100mgL−1 on mild steel surfaces in sour brine by linear polarization resistance and potentiodynamic curves. These experiments prove that these derivatives present top efficiencies of 54% and 68% for butyl and phenyl moieties, respectively. In addition, these two compounds were tested in vitro against Bacillus subtilis (Gram-positive, strain ATCC 6633), Escherichia coli (Gram-negative, strain DH5) and Pseudomonas fluorescens strains to assess their bactericidal activities, being more effective for the E. coli strain, at concentrations as low as 25mgL−1. Moreover, in order to correlate different activities and ascertain homologous action mechanisms, the two derivatives were tested for their asphaltene inhibition/dispersion activity. The results suggest that the presence of the four n-butyl moieties provide the needed amphiphillic balance to obtain better efficiencies in the tested activities. A new class of bis-di-organotin (IV) compounds were synthesized in good yields (ca. 80%) by a one-step five molecules reaction in which intervene two molecular equivalents of leucine, one of 5,5′-methylene-bis-salicylaldehyde and either two of di-n-butyltin (IV) or diphenyltin (IV) oxides, that independently provided two bis-di-organotin derivatives. The structures of these two compounds were established by 1H, 13C and 119Sn NMR, as well as by IR and elemental analysis. In both cases the 119Sn chemical shifts are characteristic of pentacoordinated atoms in solution of non-coordinating solvent (CDCl3). Once characterized, the novel compounds were tested as corrosion inhibitors at 25, 50 and 100mgL−1 on mild steel surfaces in sour brine by linear polarization resistance and potentiodynamic curves. These experiments prove that these derivatives present top efficiencies of 54% and 68% for