Cheng, Houping, Liu, Yan, Ruan, Yixiang, He, Yuchen, Wang, Xinyu, Xuan, Jun, Shen, Xiaodong, Ye, Ning and Mo, Yiming (2024) Pyridine N-oxide mediators for electrochemical benzylic C–H oxygenation. ACS Electrochemistry. ISSN 2997-0571

Abstract

Abstract: The electrooxidation of ubiquitous benzylic C(sp3)–H bonds offers a sustainable pathway to synthesize value-added carbonyl compounds. However, the lack of a versatile electrocatalytic system to accommodate the structural diversity of compounds containing benzylic C-H bonds hinders the practical implementation of electrochemical benzylic C-H oxidation technology. Herein, we designed and evaluated a library of electrochemical hydrogen atom transfer (HAT) mediators, derived from pyridine N-oxides, for the selective carbonylation of benzylic C(sp3)–H bonds. The O-H bond dissociation energy and oxidation potential can be finetuned by modifying the electronic properties of functional groups on the pyridine N-oxide, thus offering a facile way to adjust HAT characteristics to suit the target benzylic C-H bonds. A predictive neural network model was constructed based on experimental high-throughput screening data to map the quantitative structure-activity relationship (QSAR) for catalyst-substrate pairs. In addition, the practicality of the developed electrocatalytic system was demonstrated with a good substrate scope and scalability to achieve gram scale synthesis using a flow electrochemical reactor.

Item Type:	Article
Date Deposited:	31 Oct 2024 00:45
Last Modified:	31 Oct 2024 00:45
URI:	https://oak.novartis.com/id/eprint/53919