Interfacial nanoarchitectonics of nickel phosphide supported on activated carbon for transfer hydrogenation of nitroarenes under mild conditions

• Published in: Journal of colloid and interface science 2024-03, Vol.657, p.449-462
• Main Authors: Sharma, Devendra, Choudhary, Priyanka, Kumar, Sahil, Krishnan, Venkata
• Format: Article
• Language: English
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2023.11.164

Metal phosphides are promising catalysts for hydrogenation reactions due to their unique ability to generate active hydrogen species which are essential for desired reactions. In this work, the hydrogenation potential of nickel phosphide (Ni P) is explored for the transfer hydrogenation of aromatic nitro compounds using hydrazine hydrate as hydrogen source. The Ni P was supported on activated carbon (AC) to facilitate highly exposed active reaction sites. The as-synthesized Ni P-AC catalyst showed excellent catalytic potential for the hydrogenation of nitro compounds to corresponding amines with 100% conversion efficiency and resulted in excellent yields. The reaction conditions were optimized by varying different reaction parameters, such as time, temperature, solvents, catalyst amount and hydrogen sources. The developed reaction protocol is highly selective for nitro compounds having reduction susceptible functional groups like -Cl, -Br, -CHO, etc. The structure-activity relationship of the Ni P-AC was also examined which suggested that both acidic and basic sites present in Ni P-AC catalyst plays crucial role in hydrogenation reaction. Besides, an in-depth insight into the reaction mechanism illustrates that the reaction proceeds via N-phenyl hydroxylamine as the reaction intermediate. In addition, decent recyclability and stability of Ni P-AC catalyst demonstrates its highly versatile nature for potential large-scale applications. The use of highly efficient Ni P-AC catalyst for hydrogenation reactions can lead the way towards sustainable and effective industrial organic catalysis.