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Enantioselective, Visible Light Mediated Aza Paterno-Buchi Reactions of Quinoxalinones.

ABSTRACT: 3-Substituted quinoxalin-2(1H)-ones and various aryl-substituted or tethered olefins underwent an enantioselective, inter- or intramolecular aza Paternò-Büchi reaction upon irradiation at ?=420?nm in the presence of a chiral sensitizer (10?mol?%). For the intermolecular reaction with 1-arylethenes as olefin components, the scope of the reaction was studied (14 examples, 50-99?% yield, 86-98?% ee). The absolute and relative configuration of the products were elucidated by single-crystal X-ray crystallography. The reaction is suggested to occur by triplet energy transfer in a hydrogen-bonded 1:1 complex between the imine substrate and the catalyst. The intramolecular cycloaddition, consecutive reactions of the product azetidines, and an alternative reaction mode of quinoxalinones were investigated in preliminary experiments.

SUBMITTER: Li X

PROVIDER: S-EPMC7898282 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Enantioselective, Visible Light Mediated Aza Paternò-Büchi Reactions of Quinoxalinones.

Li Xinyao X Großkopf Johannes J Jandl Christian C Bach Thorsten T

Angewandte Chemie (International ed. in English) 20201201 5

3-Substituted quinoxalin-2(1H)-ones and various aryl-substituted or tethered olefins underwent an enantioselective, inter- or intramolecular aza Paternò-Büchi reaction upon irradiation at λ=420 nm in the presence of a chiral sensitizer (10 mol %). For the intermolecular reaction with 1-arylethenes as olefin components, the scope of the reaction was studied (14 examples, 50-99 % yield, 86-98 % ee). The absolute and relative configuration of the products were elucidated by single-crystal X-ray cry ...[more]

PMID: 33084097

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