Electrochemical activation of C–H by electron-deficient W2C nanocrystals for simultaneous alkoxylation and hydrogen evolution
Xiu Lin, Shi‐Nan Zhang, Dong Xu, Junjun Zhang, Yun‐Xiao Lin, Guangyao Zhai, Hui Su, Zhong‐Hua Xue, Xi Liu, Markus Antonietti, Jie‐Sheng Chen, Xin‐Hao Li
Abstract
Abstract The activation of C–H bonds is a central challenge in organic chemistry and usually a key step for the retro-synthesis of functional natural products due to the high chemical stability of C–H bonds. Electrochemical methods are a powerful alternative for C–H activation, but this approach usually requires high overpotential and homogeneous mediators. Here, we design electron-deficient W 2 C nanocrystal-based electrodes to boost the heterogeneous activation of C–H bonds under mild conditions via an additive-free, purely heterogeneous electrocatalytic strategy. The electron density of W 2 C nanocrystals is tuned by constructing Schottky heterojunctions with nitrogen-doped carbon support to facilitate the preadsorption and activation of benzylic C–H bonds of ethylbenzene on the W 2 C surface, enabling a high turnover frequency (18.8 h −1 ) at a comparably low work potential (2 V versus SCE). The pronounced electron deficiency of the W 2 C nanocatalysts substantially facilitates the direct deprotonation process to ensure electrode durability without self-oxidation. The efficient oxidation process also boosts the balancing hydrogen production from as-formed protons on the cathode by a factor of 10 compared to an inert reference electrode. The whole process meets the requirements of atomic economy and electric energy utilization in terms of sustainable chemical synthesis.