Probing the Anions Mediated Associative Behavior of Tin-12 Oxo-Macrocations by Pulsed Field Gradient NMR Spectroscopy

¹H PFG NMR spectroscopy has been used to evidence the association of ditopic {(BuSn)₁₂O₁₄(OH)₆}²⁺ macrocations when sulfate or oxalate divalent anions are used to balance their positive charges. The existence of supramolecular species, the size of which can reach up to about 10 times the size of the individual building blocks, is clearly related to electrostatic interactions as the supramolecular species fully break down to their individual components in solvent with high dielectric constant.