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Synthesis of an Oxygen-Carrying [Cosalen]2 Complex
Published on: April 30, 2023
Cobalt-Catalyzed Cyclization/Hydroboration of 1,6-Diynes with Pinacolborane
Qiang Huang1, Meng-Yang Hu1, Shou-Fei Zhu1
1State Key Laboratory and Institute of Elemento-Organic Chemistry , College of Chemistry, Nankai University , Tianjin 300071 , China.
Abstract:
Herein, we report a protocol for cyclization/hydroboration of 1,6-diynes with pinacolborane using a cobalt catalyst generated in situ from a Co(II)-phenanthroline complex, tetrabutylammonium fluoride, and pinacolborane. This protocol, which features good functional group tolerance, a broad substrate scope, and excellent stereoselectivity, enables the synthesis of useful cyclic 1,3-dienylboron compounds from readily accessible feedstocks. The proposed mechanism involves low-valent cobalt-promoted cyclometalation and subsequent hydroboration, as indicated by control experiments. Our findings demonstrate that combining hydroboration with C-C bond formation is an efficient way to synthesize structurally diverse organoboranes.
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