Abstract
C‒H activation of simple molecules to provide corresponding functionalized analogues has gained immense prominence. While this is widely applicable to a range of organic motifs, regioselectivity and most importantly site-selectivity of distal C‒H bonds remains a significant challenge. While covalently attached directing groups have been designed to solve the puzzle, their profound impact on the step-economy and substrate biasness cause a significant dent in the applicability of the protocol. To overcome this, weak non-covalent interactions between substrate and ligands have been developed but have been mainly explored with Ir-catalysis. Herein we aim to execute an unprecedented Pd catalyzed meta-selective C‒H functionalization of simple amines harnessing weak non-covalent interactions between anionic H-bond donor and neutral acceptor. Catalytic amount of organic salt acts as an anionic ligand and is suitable for efficient meta-selective C‒H olefination. Experimental and computational studies elucidate the mechanistic understanding and suggest that site-selectivity is governed by the key H-bonding interaction between an anionic donating ligand and a neutral accepting substrate. The protocol can be further extended to amines with variable linker-lengths, outlining the versatility and applicability of our methodology to organic motifs, while utilizing only a catalytic amount of directing ligand for the functionalization.
Supplementary materials
Title
Non-Covalent Interaction within Catalytic Anionic Donor and Neutral Acceptor to Promote Pd-Catalyzed Distal Site- selective Functionalization of Amines
Description
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