Palladium-catalyzed cross-coupling of alcohols with olefins by positional tuning of a counteranion

• 成果类型: Article
• 署名作者: Kaster, Sven H. M.; Zhu, Lei; Lyon, William L.; Ma, Rulin; Ammann, Stephen E.; White, M. Christina
• 署名单位: University of Illinois System; University of Illinois Urbana-Champaign
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-8137
• DOI: 10.1126/science.ado8027
• 发表日期: 2024-09-06
• 页码: 1067-1076
• 关键词: allylic etherification; c-h; alpha-allylation; efficient method; ACID; bond; sulfoxide; complexes; diffusion; strategy

摘要

Transition metal-catalyzed cross-couplings have great potential to furnish complex ethers; however, challenges in the C(sp(3))-O functionalization step have precluded general methods. Here, we describe computationally guided transition metal-ligand design that positions a hydrogen-bond acceptor anion at the reactive site to promote functionalization. A general cross-coupling of primary, secondary, and tertiary aliphatic alcohols with terminal olefins to furnish >130 ethers is achieved. The mild conditions tolerate functionality that is prone to substitution, elimination, and epimerization and achieve site selectivity in polyol settings. Mechanistic studies support the hypothesis that the ligand's geometry and electronics direct positioning of the phosphate anion at the pi-allyl-palladium terminus, facilitating the phosphate's hydrogen-bond acceptor role toward the alcohol. Ligand-directed counteranion positioning in cationic transition metal catalysis has the potential to be a general strategy for promoting challenging bimolecular reactivity.