Designed Flavins for Catalysis

Tailor-Made Catalysts - New Reactivity - Selective Editing

Flavin News: Our Research Activity

Molecular Flavin Catalysts for C-H Functionalisation and Derivatisation of Dehydroamino Acids

A. Rehpenn, A. Walter, G. Storch, Chem. Sci. 2022, accepted.

Quinoid flavin photocatalysts undergo reversible covalent C-C bond formation with diene and dehydroamino acid substrates. These C-C bonds are broken by addition of the persistent radical TEMPO, which results in hydroxylamine products in a catalytic fashion. We show a series of dehydroamino acid substrates and the follow-up chemistry of acylimine products.

Reduced Molecular Flavins as Single-Electron Reductants after Photoexcitation

R. Foja, A. Walter, C. Jandl, E. Thyrhaug, J. Hauer, G. Storch, J. Am. Chem. Soc. 2022, 144, 4721‒4726.

Flavins are not just oxidants - they are excellent reductants as well! Inspired by the activity of DNA photolyase, Richard successfully searched for conditions to replace the rare-earth reductant samarium(II)iodide by flavin catalysis and discovered a mild procedure using gamma-terpinene as stoichiometric reductant.

Photochemical Deracemization of Chiral Alkenes via Triplet Energy Transfer

T. Kratz, P. Steinbach, S. Breitenlechner, G. Storch, C. Bannwarth, T. Bach, J. Am. Chem. Soc. 2022, 144, 10133‒10138.

This collaborative study with the Bach and Bannwath groups contains an in-depth study of the mechanism of the triplet-sensitised deracemization of axially chiral alkene substrates. Key to understanding the high enantiomeric excess was the analysis of different pathways to the conical intersections in both diastereomeric catalyst-substrates complexes.

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

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

In a collaboration with the Bach Lab, we were interested in the different molecular geometries of assemblies between hydantoin substrates and a chiral photocatalyst. Fascinatingly, the different binding of enantiomeric substrates allows very efficient deracemization via hydrogen atom transfer (HAT).

Molecular Editing of Flavins for Catalysis

A. Rehpenn, A. Walter, G. Storch, Synthesis 2021, 53, 2583‒2593.

In this Short Review, we give an overview of current strategies in tailoring molecular flavins  for specific catalytic applications. We put special emphasis on linking the position of modification to changes in catalyst activity.

Synthetic C‐6 Aminoflavin Catalysts Enable Aerobic Bromination of Oxidation‐Prone Substrates

A. Walter, G. Storch, Angew. Chem. Int. Ed. 2020, 59, 2250522509.

Our first independent group's research paper describes synthetic flavin catalysts, which allow bromination of tyrosine derivatives and other oxidation-prone substrates. We use inorganic halide salt and capitalize on reactivity that is known with flavoenzymes.

Site‐Selective Nitrene Transfer to Conjugated Olefins Directed by Oxazoline Peptide Ligands

G. Storch, N. van den Heuvel, S. J. Miller, Adv. Synth. Catal. 2020, 362, 289–294.

A Fast and Reliable Screening Setup for Homogeneous Catalysis with Gaseous Reactants at Extreme Temperatures and Pressures

M. Siebert, G. Storch, O. Trapp, Org. Proc. Res. Dev. 2020, 24, 1304–1309.

Intramolecular [2+2] Photocycloaddition of Cyclic Enones: Selectivity Control by Lewis Acids and Mechanistic Implications

S. Poplata, A. Bauer, G. Storch, T. Bach, Chem. Eur. J. 2019, 25, 8135–8148.

Terahertz Spectroscopy of Tetrameric Peptides

J. Neu, E. A. Stone, J. A. Spies, G. Storch, A. S. Hatano, B. Q. Mercado, S. J. Miller, C. A. Schmuttenmaer, J. Phys. Chem. Lett. 2019, 10, 2624–2628.

Troponoid Atropisomerism: Studies on the Configurational Stability of Tropone-Amide Chiral Axes

D. R. Hirsch, A. J. Metrano, E. A. Stone, G. Storch, S. J. Miller, R. P. Murelli, Org. Lett. 2019, 21, 2412–2415.

A Stereodynamic Redox-Interconversion Network of Vicinal Tertiary and Quaternary Carbon Stereocenters in Hydroquinone-Quinone Hybrid Dihydrobenzofurans

G. Storch, B. Kim, B. Q. Mercado, S. J. Miller, Angew. Chem. Int. Ed. 2018, 57, 15107–15111.

Supramolecular chirality transfer in stereodynamic catalysts

G. Storch, O. Trapp, Chirality 2018, 30, 1150–1160.

Investigation of Strain-Promoted Azide–Alkyne Cycloadditions in Aqueous Solutions by Capillary Electrophoresis

J. Steflova, G. Storch, S. Wiesner, S. Stockinger, R. Berg, O. Trapp, J. Org. Chem. 2018, 83, 604–613.

Attracting Enantiomers: Chiral Analytes That Are Simultaneously Shift Reagents Allow Rapid Screening of Enantiomeric Ratios by NMR Spectroscopy

G. Storch, M. Haas, O. Trapp, Chem. Eur. J. 2017, 23, 2017, 5414–5418.

Stereodynamic Quinone–Hydroquinone Molecules That Enantiomerize at sp3-Carbon via Redox-Interconversion

B. Kim, G. Storch, G. Banerjee, B. Q. Mercado, J. Castillo-Lora, G. W. Brudvig, J. M. Mayer, S. J. Miller, J. Am. Chem. Soc. 2017, 139, 15239–15244.

By-design enantioselective self-amplification based on non-covalent product–catalyst interactions

G. Storch, O. Trapp, Nat. Chem. 20179, 179–187.

Temperature-Controlled Bidirectional Enantioselectivity in Asymmetric Hydrogenation Reactions Utilizing Stereodynamic Iridium Complexes

M. Siebert, G. Storch, F. Rominger, O. Trapp, Synthesis 2017, 49, 3485–3494.

A stereodynamic phosphoramidite ligand derived from 3,3′-functionalized ortho -biphenol and its rhodium(I) complexen A stereodynamic phosphoramidite ligand derived from 3,3′‐functionalized ortho‐biphenol and its rhodium(I) complex

G. Storch, L. Deberle, J.-M. Menke, F. Rominger, O. Trapp, Chirality 2016, 28, 744–748.

Rotational Barriers of Substituted BIPHEP Ligands: A Comparative Experimental and Theoretical Study

G. Storch, F. Maier, P. Wessig, O. Trapp, Eur. J. Org. Chem., 2016, 5123–5126.

Stereodynamic tetrahydrobiisoindole “NU-BIPHEP(O)”s: functionalization, rotational barriers and non-covalent interactions

G. Storch, S. Pallmann, F. Rominger, O. Trapp, Beilstein J. Org. Chem. 2016, 12, 1453–1458.

Temperature-Controlled Bidirectional Enantioselectivity in a Dynamic Catalyst for Asymmetric Hydrogenation

G. Storch, O. Trapp, Angew. Chem. Int. Ed. 2015, 54, 3580–3586.

Tautomerization-Mediated Molecular Switching Between Six- and Seven-Membered Rings Stabilized by Hydrogen Bonding

G. Storch, M. J. Spallek, F. Rominger, O. Trapp, Chem. Eur. J. 2015, 21, 8939–8945.

CuII-selective bispidine–dye conjugates

D. Brox, P. Comba, D.-P. Herten, E. Kimmle, M. Morgen, C. L. Rühl, A. Rybina, H. Stephan, G. Storch, H. Wadepohl, J. Inorg. Biochem. 2015, 148, 78–83.

5,5′-Diamino-BIPHEP ligands bearing small selector units for non-covalent binding of chiral analytes in solution

G. Storch, M. Siebert, F. Rominger, O. Trapp, Chem. Commun. 2015, 51, 15665–15668.

Skeleton Decoration of NHCs by Amino Groups and its Sequential Booster Effect on the Palladium-Catalyzed Buchwald-Hartwig Amination

Y. Zhang, V. César, G. Storch, N. Lugan, G. Lavigne, Angew. Chem. Int. Ed. 2014, 53, 6482–6486.

Synthesis of Molecular Gallium Hydrides by Means of Low-Temperature Catalytic Dehydrogenation

D. Rudolf, G. Storch, E. Kaifer, H.-J. Himmel, Eur. J. Inorg. Chem. 2012, 2368–2372.

Straightforward Synthesis of Poly(dimethylsiloxane) Phases with Immobilized (1R)-3-(Perfluoroalkanoyl)camphorate Metal Complexes and Their Application in Enantioselective Complexation Gas Chromatography

M. J. Spallek, G. Storch, O. Trapp, Eur. J. Org. Chem. 2012, 3929–3945.