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Cobalt-catalyzed deoxygenative triborylation of allylic ethers to access 1,1,3-triborylalkanes.

ABSTRACT: Polyborylated organic compounds have been emerging as versatile building blocks in chemical synthesis. Here we report a selective cobalt-catalyzed deoxygenative 1,1,3-triborylation reaction of allylic ethers with pinacolborane to prepare 1,1,3-triborylalkane compounds. With naturally abundant and/or synthetic cinnamic methyl ethers as starting materials, we have achieved the synthesis of a variety of 1,1,3-triborylalkanes (25 examples). The synthetic utility of these 1,1,3-triborylalkanes is demonstrated through site-selective allylation, protodeborylation, and consecutive carbon-carbon bond-forming reactions. Mechanistic studies including deuterium-labeling and control experiments suggest that this 1,1,3-triborylation reaction proceeds through initial cobalt-catalyzed deoxygenative borylation of allylic ethers to form allylic boronates followed by cobalt-catalyzed 1,1-diborylation of the resulting allylic boronates.

SUBMITTER: Teo WJ

PROVIDER: S-EPMC7562742 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Cobalt-catalyzed deoxygenative triborylation of allylic ethers to access 1,1,3-triborylalkanes.

Teo Wei Jie WJ Yang Xiaoxu X Poon Yeng Yeng YY Ge Shaozhong S

Nature communications 20201015 1

Polyborylated organic compounds have been emerging as versatile building blocks in chemical synthesis. Here we report a selective cobalt-catalyzed deoxygenative 1,1,3-triborylation reaction of allylic ethers with pinacolborane to prepare 1,1,3-triborylalkane compounds. With naturally abundant and/or synthetic cinnamic methyl ethers as starting materials, we have achieved the synthesis of a variety of 1,1,3-triborylalkanes (25 examples). The synthetic utility of these 1,1,3-triborylalkanes is dem ...[more]

PMID: 33060600

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