Catalyst-free N-dealkylation of aniline derivatives in water induced by high frequency ultrasound

Abstract

Here we report that cavitation bubbles, formed by the ultrasonic irradiation of a liquid at a high frequency, induces the catalyst-free N-dealkylation of aniline derivatives in water, thus opening an alternative pathway to current technologies which require transition metals and hazardous solvents or oxidants. Mechanism investigations revealed that the N-dealkylation of aniline derivatives takes place at the cavitation bubble-water interface, a region where N-C bond thermal cracking reactions occur. Advantageously, the N-dealkylation of aniline derivatives can also specifically occur in the presence of other components thanks to their strong interaction at the cavitation bubble-water interface. This specific transfer of the acoustic energy to aniline derivatives represents a notable advantage over current cracking technologies, which lead to non-chemical specific cracking due to the heating of the whole reactor