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Nickel-catalyzed cross-coupling of chromene acetals and boronic acids.

ABSTRACT: A modular and highly efficient protocol for the synthesis of 2-aryl- and heteroaryl-2H-chromenes is described. Under base-free conditions, readily accessible 2-ethoxy-2H-chromenes undergo C(sp(3))-O activation and C(sp(3))-C bond formation in the presence of an inexpensive nickel catalyst and boronic acids. This new strategy enables broad access to 2-substituted-2H-chromenes and has been applied to the late-stage incorporation of complex molecules, including the pharmaceuticals loratidine and indomethacin methyl ester.

SUBMITTER: Graham TJ

PROVIDER: S-EPMC4804347 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature

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Nickel-catalyzed cross-coupling of chromene acetals and boronic acids.

Graham Thomas J A TJ Doyle Abigail G AG

Organic letters 20120302 6

A modular and highly efficient protocol for the synthesis of 2-aryl- and heteroaryl-2H-chromenes is described. Under base-free conditions, readily accessible 2-ethoxy-2H-chromenes undergo C(sp(3))-O activation and C(sp(3))-C bond formation in the presence of an inexpensive nickel catalyst and boronic acids. This new strategy enables broad access to 2-substituted-2H-chromenes and has been applied to the late-stage incorporation of complex molecules, including the pharmaceuticals loratidine and in ...[more]

PMID: 22385385

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