Practical electrochemical hydrogenation of nitriles at the nickel foam cathode†

Abstract

We report a scalable hydrogenation method for nitriles based on cost-effective materials in a very simple two-electrode setup under galvanostatic conditions. All components are commercially and readily available. The method is very easy to conduct and applicable to a variety of nitrile substrates, leading exclusively to primary amine products in yields of up to 89% using an easy work-up protocol. Importantly, this method is readily transferable from the milligram scale in batch-type screening cells to the multi-gram scale in a flow-type electrolyser. The transfer to flow electrolysis enabled us to achieve a notable 20 g day⁻¹ productivity of phenylethylamine at a geometric current density of 50 mA cm⁻² in a flow-type electrolyser with 48 cm² electrodes. It is noteworthy that this method is sustainable in terms of process safety and reusability of components.