Hydrogen bonding template enables remote meta-C–H alkenylation of nitroarenes with electron-deficient alkenes
摘要
Regioselective distal C−H functionalization of nitroarenes by overriding proximal C−H activation has remained an unsolved challenge. Herein, we present a palladium-catalyzed meta-C−H alkenylation of nitroarene substrate, achieved through leveraging the non-covalent hydrogen bonding interactions. Urea-based templates comprising an elongated biphenyl linker designed in such a way that it interacts with nitro group via strong hydrogen bonding interaction, while a cyano based directing group is attached along the template to coordinate with the palladium center, thereby facilitating the activation of the remote meta-C−H bond of nitrobenzene. Computational mechanistic investigation and the analysis of non-covalent interaction deciphers the crucial role of H-bonding in regulating the regioselectivity.