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Published on: November 30, 2022
Rhodium-Catalyzed Remote Borylation of Alkynes and Vinylboronates
Minghao Zhang1, Zheming Liu1, Wanxiang Zhao1
1State Key Laboratory of Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, 410082, Hunan, Changsha, P. R. China.
Abstract:
Remote functionalization involving a fascinating chain-walking process has emerged as a powerful strategy for the rapid access to value-added functional molecules from readily available feedstocks. However, the scope of current methods is predominantly limited to mono- and di-substituted alkenes. The remote functionalization of multi- and heteroatom-substituted alkenes is challenging, and the use of alkynes in the chain walking is unexplored. We herein report a rhodium catalyzed remote borylation of internal alkynes, offering an unprecedented reaction mode of alkynes for the preparation of synthetically valuable 1,n-diboronates. The regioselective distal migratory hydroboration of sterically hindered tri- and tetra-substituted vinylboronates is also demonstrated to furnish various multi-boronic esters. Synthetic utilities are highlighted through the selective manipulation of the two boryl groups in products such as the regioselective cross coupling, oxidation, and amination.
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