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Synergistic Catalysis of Tandem Michael Addition/Enantioselective Protonation Reactions by an Artificial Enzyme.

ABSTRACT: Enantioselective protonation is conceptually one of the most attractive methods to generate an α-chiral center. However, enantioselective protonation presents major challenges, especially in water. Herein, we report a tandem Michael addition/enantioselective protonation reaction catalyzed by an artificial enzyme employing two abiological catalytic sites in a synergistic fashion: a genetically encoded noncanonical p-aminophenylalanine residue and a Lewis acid Cu(II) complex. The exquisite stereocontrol achieved in the protonation of the transient enamine intermediate is illustrated by up to >20:1 dr and >99% ee of the product. These results illustrate the potential of exploiting synergistic catalysis in artificial enzymes for challenging reactions.

SUBMITTER: Zhou Z

PROVIDER: S-EPMC8353628 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Synergistic Catalysis of Tandem Michael Addition/Enantioselective Protonation Reactions by an Artificial Enzyme.

Zhou Zhi Z Roelfes Gerard G

ACS catalysis 20210713 15

Enantioselective protonation is conceptually one of the most attractive methods to generate an α-chiral center. However, enantioselective protonation presents major challenges, especially in water. Herein, we report a tandem Michael addition/enantioselective protonation reaction catalyzed by an artificial enzyme employing two abiological catalytic sites in a synergistic fashion: a genetically encoded noncanonical p-aminophenylalanine residue and a Lewis acid Cu(II) complex. The exquisite ...[more]

PMID: 34386272

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