Photocatalyzed H2‑Acceptorless Dehydrogenative Borylation by Using Amine Borane

• Published in: ACS catalysis 2024-06, Vol.14 (11), p.8666-8675
• Main Authors: Jiang, Hao-Wen, Yu, Wan-Lei, Wang, Dong, Xu, Peng-Fei
• Format: Article
• Language: English
• ISSN: 2155-5435; 2155-5435
• DOI: 10.1021/acscatal.4c00401

Catalytic dehydrogenative borylation of alkenes is arguably the most straightforward approach for synthesizing alkenyl boronates, as it eliminates the need for alkene or boranes prefunctionalizion. While transition-metal catalysis has conventionally been employed for this transformation, competitive side reactions including hydroborylation, overborylation, and regioisomer formation always exist. In this study, we present a radical approach for catalytic dehydrogenative borylation, which involves the synergistic merger of photoredox/HAT/cobalt catalysis, thereby circumventing the necessity for noble metals, sacrificial hydrogen acceptors, and high temperatures. This method employs stable and cost-effective amine borane reagents as feedstocks, resulting in the sole byproduct of H2. This dehydrogenative borylation methodology facilitates the conversion of a diverse array of functionalized alkenes into valuable organoboron reagents. Furthermore, the late-stage borylation of complex molecules demonstrates high levels of site selectivity.