The past decade saw an exponential growth in the area of nanoscience and nanotechnology. One of the most interesting features of nanotechnology is its useful applications in various fields. The discovery and easy accessibility of nanoparticles (NPs) of different shapes, sizes, and compositions have prompted investigations on their applications in catalysis. The “nano” in nanocatalysis refers to the size of the particles in the nanoscale range. As nanoparticles have a high surface-to-volume ratio, compared to bulk materials, they offer a viable alternative to conventional catalysts [1, 2]. Recent reports have showed their remarkable performance as catalysts, in terms of reactivity, selectivity, and product yields [3, 4, 5, 6, 7, 8]. Nanocatalysts offer numerous advantages over convention catalyst systems, but isolation and recovery of these small nanocatalysts from the reaction mixture is tedious. The development of an efficient, and industrially and environmentally acceptable catalyst constitutes one of the important goals towards sustainability and economic growth. To achieve this goal, the use of magnetic nanoparticles has received much interest as they are easily separable and reusable. Thus, magnetic nanoparticles have appeared as a practical alternative. Their magnetic and insoluble properties offer easy and efficient separation of the catalyst from the reaction mixture – by the application of an external magnet without the requirement of filtration, centrifugation, or other complex workup.

Carbon-nitrogen (C–N) bond formation is one of the useful processes in organic synthesis, as the consequent amines are broadly used as intermediates or precursors in the preparation of fine chemicals, pharmaceuticals, agrochemicals, and natural products. The developments in the formation of carbon-nitrogen bonds and in the synthesis of related heterocycles by magnetic metal nanoparticles as catalysts have been described below.