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Redox deracemization of β,γ-alkynyl α-amino esters.

ABSTRACT: The first non-enzymatic redox deracemization method using molecular oxygen as the terminal oxidant has been described. The one-pot deracemization of β,γ-alkynyl α-amino esters consisted of a copper-catalyzed aerobic oxidation and chiral phosphoric acid-catalyzed asymmetric transfer hydrogenation with excellent functional group compatibility. By using benzothiazoline as the reducing reagent, an exclusive chemoselectivity at the C[double bond, length as m-dash]N bond over the C[triple bond, length as m-dash]C bond was achieved, allowing for efficient deracemization of a series of α-amino esters bearing diverse α-alkynyl substituent patterns. The origins of chemo- and enantio-selectivities were elucidated by experimental and computational mechanistic investigation. The generality of the strategy is further demonstrated by efficient deracemization of β,γ-alkenyl α-amino esters.

SUBMITTER: Zhang L

PROVIDER: S-EPMC8159540 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Redox deracemization of β,γ-alkynyl α-amino esters.

Zhang Lu L Zhu Rongxiu R Feng Aili A Zhao Changyin C Chen Lei L Feng Guidong G Liu Lei L

Chemical science 20200421 17

The first non-enzymatic redox deracemization method using molecular oxygen as the terminal oxidant has been described. The one-pot deracemization of β,γ-alkynyl α-amino esters consisted of a copper-catalyzed aerobic oxidation and chiral phosphoric acid-catalyzed asymmetric transfer hydrogenation with excellent functional group compatibility. By using benzothiazoline as the reducing reagent, an exclusive chemoselectivity at the C[double bond, length as m-dash]N bond over the C[triple bond, length ...[more]

PMID: 34122901

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