Description
Main areas of research:
Development of new active recyclable organocatalysts for the asymmetric synthesis of chiral biologically active substances;
The use of sub- and supercritical CO2, ionic liquids and fluorinated alcohols as alternatives to traditional organic solvents and catalysts for the production of practically important organic compounds of various classes (green chemistry).
Main achievements:
A new direction of asymmetric catalysis has been developed, involving the use of chiral ionic liquids and related compounds as regenerable organocatalysts for asymmetric organic reactions [“Ionic Liquid Organocatalysts”, in Comprehensive Enantioselective Organocatalysis: Catalysts, Reactions, and Applications, ed. P.I. Dalco, Wiley-VCH, 2013, v. 2, p. 617-650; Russ. Chem. Bull., Int. Ed., 2012, 61, 1313; Usp. Chem., 2011, 80, 1119; 2009, 78, 796]. Previously unknown organocatalysts immobilized on polyelectrolytes [poly (diallyldimethylammonium) hexafluorophosphate, sulfated polystyrene] and derivatives of natural α-amino acids (proline, serine, threonine), their amides, and other chiral amines containing incorpori were obtained. (cations of imidazole, triazole, pyridinium)
In the presence of the obtained organocatalysts (5–20 mol.%), Asymmetric aldol reactions of various stereo-directionality were carried out, including in aqueous medium, Michael reactions, proceeding according to the mechanism of iminium activation of reagents, domino-reactions, which previously could not be performed under the action of immobilized organocatalysts. Reaction products are formed under the proposed conditions with extremely high diastereo (dr up to 99: 1) and enantioselectivity (up to 99%), and catalysts, unlike the known ones, can be used repeatedly
For the first time, chiral ionic liquids have been successfully used as organocatalysts at key stages of the synthesis of chiral drugs and analogues of natural compounds. In this way, key intermediates are synthesized to obtain the most active enantiomers of drugs for the treatment of CNS diseases (Paroxetine, Phenibut, Baclofen, Rolipram) and the most important chiral b-amino acids (b-phenylalanine, b-tyrosine, b-DOPA), (S) -enantiomer widely the anticoagulant Warfarin used in the clinic, as well as polyfunctional aldoli are valuable intermediates for the synthesis of syn-configured polyols whose structural fragments are part of carbohydrates and a number of other natural compounds
An original approach is proposed for studying the transformations of organocatalysts during asymmetric reactions, including the combined use of catalysts "marked" with ionic groups and ESI (+) - MS mass spectrometry. The method is based on the fact that the mass spectra of IL contain mainly the peaks of the catalyst and the ionic compounds formed from it and are not complicated by the low-intensity peaks of molecules that do not contain ions. As a result, intermediates of catalysts with reagents and products were identified, which brought them out of the catalytic cycle, and a simple and effective way to prolong their service life was proposed. The data obtained are useful for the development on their basis of organocatalysts and organocatalytic processes suitable for practical use.
