Rhodium‐Catalyzed Remote Borylation of Alkynes and Vinylboronates. (22nd December 2022)

• Record Type: Journal Article
• Authors: Zhang, Minghao; Liu, Zheming; Zhao, Wanxiang
• Is Part Of: Angewandte Chemie. Volume 135:Number 5(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-12-22
• Subjects: Alkynes -- Borylation -- C−H Activation -- Chain-Walking -- Vinylboronates; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202215455
• Languages: English
• ISSNs: 0044-8249

Abstract

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. Abstract : The regioselective remote borylation of internal alkynes and sterically hindered tri‐ and tetra‐substituted vinylboronates enabled by rhodium catalysis is reported. The 1, n ‐diboronate products can be converted to a variety of useful building blocks, biologically active molecules, and drugs via the selective manipulation of the two boryl groups in products including the regioselective cross coupling, oxidation, and amination.