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Copper Bis(oxazoline)-Catalyzed Enantioselective Alkynylation of Benzopyrylium Ions.

ABSTRACT: The stereocontrolled construction of biologically relevant chromanones and tetrahydroxanthones has been achieved through the addition of alkynes to benzopyrylium trilfates under the influence of copper bis(oxazoline) catalysis. Excellent levels of enantiocontrol (63-98?%?ee) are achieved in the addition of a variety of alkynes to an array of chromenones with a hydrogen in the 2-position. Promising levels of enantiocontrol (54-67?%?ee) are achieved in the alkynylation of chromenones with esters in the 2-position, generating tertiary ether stereocenters resembling those frequently found in naturally occurring metabolites.

SUBMITTER: Guan Y

PROVIDER: S-EPMC7262874 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Copper Bis(oxazoline)-Catalyzed Enantioselective Alkynylation of Benzopyrylium Ions.

Guan Yong Y Attard Jonathan W JW Mattson Anita E AE

Chemistry (Weinheim an der Bergstrasse, Germany) 20200128 8

The stereocontrolled construction of biologically relevant chromanones and tetrahydroxanthones has been achieved through the addition of alkynes to benzopyrylium trilfates under the influence of copper bis(oxazoline) catalysis. Excellent levels of enantiocontrol (63-98 % ee) are achieved in the addition of a variety of alkynes to an array of chromenones with a hydrogen in the 2-position. Promising levels of enantiocontrol (54-67 % ee) are achieved in the alkynylation of chromenones with esters i ...[more]

PMID: 31867810

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