Riehl Paul S, Nasrallah Daniel J, Schindler Corinna S
Willard Henry Dow Laboratory , Department of Chemistry , University of Michigan , 930 North University Avenue , Ann Arbor , Michigan 48109 , USA . Email:
Chem Sci. 2019 Sep 25;10(44):10267-10274. doi: 10.1039/c9sc03716k. eCollection 2019 Nov 28.
Transannular carbonyl-olefin metathesis reactions complement existing procedures for related ring-closing, ring-opening, and intermolecular carbonyl-olefin metathesis. We herein report the development and mechanistic investigation of FeCl-catalyzed transannular carbonyl-olefin metathesis reactions that proceed a distinct reaction path compared to previously reported ring-closing and ring-opening protocols. Specifically, carbonyl-ene and carbonyl-olefin metathesis reaction pathways are competing under FeCl-catalysis to ultimately favor metathesis as the thermodynamic product. Importantly, we show that distinct Lewis acid catalysts are able to distinguish between these pathways to enable the selective formation of either transannular carbonyl-ene or carbonyl-olefin metathesis products. These insights are expected to enable further advances in catalyst design to efficiently differentiate between these two competing reaction paths of carbonyl and olefin functionalities to further expand the synthetic generality of carbonyl-olefin metathesis.
跨环羰基-烯烃复分解反应补充了现有的相关闭环、开环和分子间羰基-烯烃复分解程序。我们在此报告了FeCl催化的跨环羰基-烯烃复分解反应的开发和机理研究，该反应与先前报道的闭环和开环方案相比，具有独特的反应路径。具体而言，在FeCl催化下，羰基-烯反应和羰基-烯烃复分解反应路径相互竞争，最终有利于复分解反应作为热力学产物。重要的是，我们表明不同的路易斯酸催化剂能够区分这些路径，从而选择性地形成跨环羰基-烯或羰基-烯烃复分解产物。这些见解有望推动催化剂设计的进一步进展，以有效区分羰基和烯烃官能团的这两种竞争反应路径，从而进一步扩大羰基-烯烃复分解反应的合成通用性。
