A study of the extraction of copper salts from aqueous solutions into an equimolar solution of a long-chain amine and a long-chain carboxylic acid in toluene has shown that a cationic copper aggregate is formed in the organic phase. A mechanism of the extraction process and a model structure of the aggregate are proposed based on UV-visible, and NMR spectra, water solubilization, and computer-aided model design (CAMD).