Szilvia Deák

Bio: Szilvia Deák is an academic researcher from Budapest University of Technology and Economics. The author has contributed to research in topics: Enantioselective synthesis & Diethylzinc. The author has an hindex of 5, co-authored 9 publications receiving 60 citations.

Steric and electronic tuning of atropisomeric amino alcohol type ligands with a 1-arylpyrrole backbone

Abstract: The synthesis of new, trifluoromethyl group containing atropisomeric amino alcohols and their application in enantioselective diethylzinc additions to aldehydes is described. A significant improvement of the enantioinductive effects of the new ligands by increasing the Bronsted acidity and bulkiness of the triarylcarbinol moiety is also reported. Tuning was achieved by the introduction of phenyl substituents containing two trifluoromethyl groups onto the α-carbon of the tertiary alcohol part of the ligand. The application of the new catalysts provided 1-(substituted phenyl)propanols with excellent enantiomeric purities.

Synthesis and Application of New, Optically Active Compounds as Catalysts and Ligands in Enantioselective Reactions

Abstract: New methods for efficient preparation of optically active compounds developed recently are reported. Combination of selective organometallic, organocatalytic, phase transfer catalytic and catalytic hydrogenation reactions provided numerous new optically active members of the families of atropisomeric 1-phenylpyrrole derivatives, 4-aminobutan-1-ol and 3,4-disubstituted pyrrolidine derivatives and optically active α- and β-aminophosphonic acids. The products can be used as valuable new chiral ligands or organocatalysts and can serve as building blocks of practically important biologically active compounds.

Organic semiconductor photocatalyst can bifunctionalize arenes and heteroarenes

Abstract: Photoexcited electron-hole pairs on a semiconductor surface can engage in redox reactions with two different substrates. Similar to conventional electrosynthesis, the primary redox intermediates afford only separate oxidized and reduced products or, more rarely, combine to one addition product. Here, we report that a stable organic semiconductor material, mesoporous graphitic carbon nitride (mpg-CN), can act as a visible-light photoredox catalyst to orchestrate oxidative and reductive interfacial electron transfers to two different substrates in a two- or three-component system for direct twofold carbon-hydrogen functionalization of arenes and heteroarenes. The mpg-CN catalyst tolerates reactive radicals and strong nucleophiles, is straightforwardly recoverable by simple centrifugation of reaction mixtures, and is reusable for at least four catalytic transformations with conserved activity.

Highly Atroposelective Synthesis of Arylpyrroles by Catalytic Asymmetric Paal–Knorr Reaction

Abstract: A general and efficient method for accessing enantiomerically pure arylpyrroles by utilizing the catalytic asymmetric Paal-Knorr reaction has been developed for the first time. A wide range of axially chiral arylpyrroles were obtained in high yields with good to excellent enantioselectivities. The key to success is the use of the combined-acid catalytic system involving a Lewis acid and a chiral phosphoric acid for achieving effective enantiocontrol. Noteworthy is that an unexpected solvent-dependent inversion of the enantioselectivity was observed in the above-mentioned asymmetric reaction.

Phosphoric acid-catalyzed atroposelective construction of axially chiral arylpyrroles

Abstract: Axially chiral arylpyrroles are key components of pharmaceuticals and natural products as well as chiral catalysts and ligands for asymmetric transformations. However, the catalytic enantioselective construction of optically active arylpyrroles remains a formidable challenge. Here we disclose a highly efficient strategy to access enantioenriched axially chiral arylpyrroles by means of organocatalytic atroposelective desymmetrization and kinetic resolution. Depending on the remote control of chiral catalyst, the arylpyrroles were obtained in high yields and excellent enantioselectivities under mild reaction conditions. This strategy tolerates a wide range of functional groups, providing a facile avenue to approach axially chiral arylpyrroles from simple and readily available starting materials. Selected arylpyrrole products proved to be efficient chiral ligands in asymmetric catalysis and also important precursors for further synthetic transformations into highly functionalized pyrroles with potential bioactivity, especially the axially chiral fully substituted arylpyrroles.