美国伊利诺伊大学M. Christina White团队报道了钯催化的反阴离子位置调谐的醇与烯烃交叉偶联反应。相关研究成果发表在2024年9月6日出版的《科学》。

过渡金属催化的交叉偶联具有提供复杂醚的巨大潜力；然而，C（sp3）-O官能化步骤中的挑战排除了其作为通用方法。

该文中，研究人员描述了计算指导的将氢键受体阴离子定位在反应位点以促进功能化的过渡金属配体设计。实现了伯、仲和叔脂肪醇与末端烯烃的一般交叉偶联，以提供>130种醚。温和的条件易于取代、消除和差向异构化的功能，并在多元醇环境中实现位点选择性。

机理研究支持这样一种假设，即配体的几何形状和电子学直接将磷酸根阴离子定位在π-烯丙基钯末端，促进磷酸根对醇的氢键受体作用。阳离子过渡金属催化中配体导向的反阴离子定位，有可能成为促进具有挑战性的双分子反应的通用策略。

附：英文原文

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

Author: Sven H. M. Kaster, Lei Zhu, William L. Lyon, Rulin Ma, Stephen E. Ammann, M. Christina White

Issue&Volume: 2024-09-06

Abstract: Transition metal–catalyzed cross-couplings have great potential to furnish complex ethers; however, challenges in the C(sp3)–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 π-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.

DOI: ado8027

Source: https://www.science.org/doi/10.1126/science.ado8027