10.1002/chem.202000720
Chemistry - A European Journal
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triplet energy of the substrates by hydrogen bonding and enables
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not affected by the substrate. The formation of a catalyst substrate
complex was proven by NMR studies and a potential structure of
the 1:1 complex was revealed by DFT calculations. A better
understanding of the binding mode and of the interaction between
the sensitizing unit and the substrate is expected to facilitate the
design of modified catalysts.
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Acknowledgement
Financial support by the European Research Council under the
European Union’s Horizon 2020 research and innovation
programme (grant agreement No 665951 ELICOS) is gratefully
acknowledged. We thank Dr. J. D. Jolliffe for his help in the
preparation of catalyst 4 and M. Eder for his assistance with the
CD measurements. J. G. thanks the Fonds der Chemischen
Industrie for funding (Kekulé fellowship), the SPP 1807
(dispersion) for intellectual support and Stephan Reichl for his
help in preparing water-free NMR-samples.
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Keywords: asymmetric catalysis • enantioselectivity • hydrogen
bonds • organocatalysis • photochemistry • sensitizers
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