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Photochemical Deracemization at sp3-Hybridized Carbon Centers via a Reversible Hydrogen Atom Transfer

Johannes Großkopf, Manuel Plaza, Antonia Seitz, Stefan Breitenlechner, Golo Storch and Thorsten Bach*

*School of Natural Sciences, Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85747 Garching, Germany, Email:

J. Großkopf, M. Plaza, A. Seitz, S. Breitenlechner, G. Storch, T. Bach, J. Am. Chem. Soc., 2021, 143, 21241-21245.

DOI: 10.1021/jacs.1c11266 (free Supporting Information)

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A chiral diarylketone catalyzes a photochemical deracemization of 5-substituted 3-phenylimidazolidine-2,4-diones. Mechanistic evidence suggests the reaction to occur by selective hydrogen atom transfer (HAT). The product enantiomer is not processed by the catalyst and is thus enriched in the photostationary state.

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proposed transition states

Key Words

hydantoins, photochemistry, organocatalysis

ID: J48-Y2021