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Copper-catalysed photoinduced decarboxylative alkynylation: a combined experimental and computational study.

ABSTRACT: Redox-active esters (RAEs) as alkyl radical precursors have demonstrated great advantages for C-C bond formation. A decarboxylative cross-coupling method is described to afford substituted alkynes from various carboxylic acids using copper catalysts CuCl and Cu(acac)₂. The photoexcitation of copper acetylides with electron-rich NEt₃ as a ligand provides a general strategy to generate a range of alkyl radicals from RAEs of carboxylic acids, which can be readily coupled with a variety of aromatic alkynes. The scope of this cross-coupling reaction can be further expanded to aliphatic alkynes and alkynyl silanes using a catalytic amount of preformed copper-phenylacetylide. In addition, DFT calculations revealed the favorable reaction pathway and that the bidentate acetylacetonate ligand of the copper intermediate plays an important role in inhibiting the homo-coupling of the alkyne.

SUBMITTER: Mao Y

PROVIDER: S-EPMC8159226 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Copper-catalysed photoinduced decarboxylative alkynylation: a combined experimental and computational study.

Mao Yu Y Zhao Wenxuan W Lu Shuo S Yu Lei L Wang Yi Y Liang Yong Y Ni Shengyang S Pan Yi Y

Chemical science 20200429 19

Redox-active esters (RAEs) as alkyl radical precursors have demonstrated great advantages for C-C bond formation. A decarboxylative cross-coupling method is described to afford substituted alkynes from various carboxylic acids using copper catalysts CuCl and Cu(acac)2. The photoexcitation of copper acetylides with electron-rich NEt3 as a ligand provides a general strategy to generate a range of alkyl radicals from RAEs of carboxylic acids, which can be readily coupled with ...[more]

PMID: 34122950

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