Sonochemically-Induced Reduction of Alkenes to Alkanes with Ammonia

With the progressive defossilization of our industry, hydrogen (H-2) has been identified as a central molecule to store renewable electricity. In this context, ammonia (NH3) is now rapidly emerging as a promising hydrogen carrier for the future. This game change indirectly impacts the field of fine chemistry where hydrogenation reactions are widely deployed. In particular, the possibility of performing hydrogenation reactions using ammonia directly instead of hydrogen has become highly desirable but it remains a very difficult scientific task, which we address in this communication. Here we show that the N-H bond of NH3 can be cleaved within cavitation bubbles, generated by ultrasonic irradiation at a high frequency, leading to the in situ formation of a diimide, which then induces the hydrogenation of alkenes. Advantageously, this work does not involve any transition metal and releases N-2 as a sole co-product.

Automated summary

With the progressive defossilization of our industry, hydrogen (H-2) has been identified as a central molecule to store renewable electricity. In this context, ammonia (NH3) is now rapidly emerging as a promising hydrogen carrier for the future. This study demonstrates a novel method of cleaving the N-H bond of NH3 within cavitation bubbles, generated by ultrasonic irradiation, leading to the in situ formation of a diimide, which then catalyzes the hydrogenation of alkenes. This work offers a potential solution for hydrogenation reactions using ammonia directly, without the need for transition metals and with N-2 as the sole co-product.