In order to study the possibility of creating products of interaction of boric acid with pectin, a number of compounds with 1: 1 pectin boric acid and 2:1 ratio were synthesized. A theoretical calculation of the possibility of complex formation using HyperChem 8.07 software by the method of molecular mechanics (force field AMBER) and semiempirical methods PM3 using the Polak-Ribier algorithm was carried out. Quantum-chemical calculation of model structures showed a high probability of forming pectin-boric acid complexes in a ratio of 2:1. The scheme of 2:1 complex formation was proposed, where a single pectin molecule forms with boric acid etheric connections through the side chains of sugars, while the second molecule of pectin forms an ester bond through the carboxyl group of the galacturonic chain. The probability of such complex formation was confirmed by method of IR spectroscopy. Samples of pure pectin and the product of its interaction with boric acid were studied. An intensive band was detected in the region of 1500-1600 cm-1 in the spectrum of pure pectin. This indicates the presence of free carboxyl groups of galacturonic acid in pectin.The relative intensity of this band decreases on the spectrum of the product of the interaction of pectin with boric acid. At the same time, lines of medium intensity appear in the region 1750-1755 cm-1 , which indicates the probable presence of a small number of ester groups that connect pectin with boric acid
complex compounds, supramolecular complexes, boric acid, pectin