A Unique Palladium-Catalyzed Heck Arylation as a Remote Trigger for Cyclopropane-Selective Ring Opening
Ilan Marek presents a palladium-catalyzed Heck arylation triggering a cyclopropane-selective ring opening.
The concept of remote functionalization, originally coined by Breslow in 1972, relates to the selective functionalization at a site away from the site of a functional group. Following this pioneering work, an impressive body of work has been reported for the remote functionalization of non-reactive molecules in the gas phase. However, after these reports, the field became rather dormant, most probably due to the synthetic difficulties encountered, until the last few years when there has been a resurgence of interest in this approach. It is now considered as one of the hottest topics in synthetic organic chemistry thanks to the contributions of worldwide leading research groups. Initially, the research group of Professor Ilan Marek (Technion – Israel Institute of Technology, Haifa, Israel) had developed the remote functionalization of hydrocarbon chains by merging two cutting-edge methods, namely the allylic C–H bond activation and C–C bond cleavage of ω-ene cyclopropanes.
The Marek group wanted to design a new system where the remote functionalization could be performed catalytically and found a palladium-catalyzed method that provides the acyclic products in good yields and selectivities as unique (E)-isomers.