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Syn-Selective alkylarylation of terminal alkynes via the combination of photoredox and nickel catalysis.

ABSTRACT: Substituted alkenes are pivotal structural motifs found in pharmaceuticals and agrochemicals. Although numerous methods have been developed to construct substituted alkenes, a generally efficient, mild, catalytic platform for the conversion of alkynes to this highly functionalized scaffold via successive C-C bond forming steps remains in high demand. Here we describe an intermolecular, regio- and syn-stereoselective alkylarylation of terminal alkynes with tertiary alkyl oxalates via photoredox-Ni dual catalysis. This catalytic protocol, synergistically combining Ir/Ni-catalyzed alkyne difunctionalization with photoinduced alkene isomerization, affords trisubstituted alkenes with excellent efficiency and syn-stereoselectivity. The mild conditions tolerate many functional groups, allowing for a broad scope with respect to terminal alkynes, aryl bromides, and alkyl oxalates.

SUBMITTER: Guo L

PROVIDER: S-EPMC6208420 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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syn-Selective alkylarylation of terminal alkynes via the combination of photoredox and nickel catalysis.

Guo Lei L Song Fan F Zhu Shengqing S Li Huan H Chu Lingling L

Nature communications 20181031 1

Substituted alkenes are pivotal structural motifs found in pharmaceuticals and agrochemicals. Although numerous methods have been developed to construct substituted alkenes, a generally efficient, mild, catalytic platform for the conversion of alkynes to this highly functionalized scaffold via successive C-C bond forming steps remains in high demand. Here we describe an intermolecular, regio- and syn-stereoselective alkylarylation of terminal alkynes with tertiary alkyl oxalates via photoredox-N ...[more]

PMID: 30382103

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